This document is a technical guide that provides an overview of variable speed drives (VSDs). It discusses why VSDs are necessary for industrial processes, examples of industrial segments that use VSD processes, and the variables that affect processing systems. The guide focuses on how electric motors are used to power machines and can be controlled by frequency converters to vary speed based on process needs. It also examines the benefits of electrical VSDs like AC drives for process control and cost savings compared to other control methods.
This technical guide provides an overview of motion control drives and synchronous servo motor technology. It discusses the differences between motion control and standard speed control systems, and decentralized versus centralized control architectures. The guide also covers various drive and motor combinations, synchronous motor principles, feedback devices, motion control concepts, and application examples. Key topics explained in more detail include synchronous servo motor operation, performance measurement, and how synchronous motors differ from induction motors.
This technical guide provides information on dimensioning drive systems. It discusses selecting induction motors based on thermal loadability, speed range and torque requirements. It also covers selecting frequency converters based on load type, current and network conditions. The guide describes motor fundamentals including torque-speed curves, current components, and power calculations. It also reviews basic mechanical laws regarding rotational motion, gears, moments of inertia, and how they impact torque requirements during acceleration and deceleration. Dimensioning involves considering all system factors like the electric supply, driven machine, and environmental conditions.
This technical guide discusses electrical braking solutions for AC drives. It begins by evaluating braking power needs based on load characteristics such as constant versus quadratic torque. It then describes various electrical braking methods available in drives, including motor flux braking, braking choppers with resistors, and IGBT regeneration units. The guide concludes by comparing the life cycle costs of different braking solutions.
This document provides an overview of harmonics with AC drives, including:
- Chapters discuss harmonic distortion sources and effects, calculation methods using DriveSize software, and standards for harmonic limits.
- DriveSize is used to model a network supplying a frequency converter and motor load, calculating the harmonic currents and voltages.
- Standards discussed include EN61800-3, IEC1000-2-2, IEC1000-2-4, IEC1000-3-2, IEC1000-3-4, and IEEE519, which set limits on harmonic distortion.
- Methods for reducing harmonics are examined, including rectifier configuration, use of inductors, and passive or active filters
This technical guide book provides 10 chapters that explain different aspects of variable speed drive technology, with a focus on Direct Torque Control (DTC). Chapter 1 introduces DTC and outlines the guide. Chapter 2 discusses the evolution of variable speed drives from early DC motor drives to modern DTC. It compares features and performance of different technologies. Chapter 3 addresses common questions about DTC performance and operation.
This technical guide discusses bearing currents in modern AC drive systems. High frequency bearing currents are generated through three main mechanisms: circulating currents induced by asymmetric capacitive currents in large motors; shaft grounding currents from voltage increases along impedance paths; and capacitive discharge currents from internal voltage divisions in small motors. Proper grounding, motor cabling, and bonding connections are necessary to prevent damage from these high frequency currents flowing through motor bearings. Specialized measurement may be needed to analyze bearing currents.
This technical guide provides information to help ensure electromagnetic compatibility (EMC) compliance when installing and configuring power drive systems (PDS). It defines key EMC terms and concepts. It describes EMC solutions related to emissions, filtering, cabling, and installation practices. Practical examples of EMC-compliant installations are also provided. The guide is intended to assist original equipment manufacturers, system integrators, and panel builders in meeting EMC directive requirements when incorporating drives and auxiliary components into their own systems.
This document provides an overview of functional safety and the requirements of the Machinery Directive. It discusses safety systems for machinery that monitor operations and ensure safe functioning. The document is divided into three parts that cover the theory of functional safety, standards related to the Machinery Directive, and steps for meeting the Directive's requirements. Ensuring functional safety helps prevent accidents and injury while allowing for productivity. The Machinery Directive defines essential health and safety requirements that machinery in the EU must fulfill.
This technical guide provides an overview of motion control drives and synchronous servo motor technology. It discusses the differences between motion control and standard speed control systems, and decentralized versus centralized control architectures. The guide also covers various drive and motor combinations, synchronous motor principles, feedback devices, motion control concepts, and application examples. Key topics explained in more detail include synchronous servo motor operation, performance measurement, and how synchronous motors differ from induction motors.
This technical guide provides information on dimensioning drive systems. It discusses selecting induction motors based on thermal loadability, speed range and torque requirements. It also covers selecting frequency converters based on load type, current and network conditions. The guide describes motor fundamentals including torque-speed curves, current components, and power calculations. It also reviews basic mechanical laws regarding rotational motion, gears, moments of inertia, and how they impact torque requirements during acceleration and deceleration. Dimensioning involves considering all system factors like the electric supply, driven machine, and environmental conditions.
This technical guide discusses electrical braking solutions for AC drives. It begins by evaluating braking power needs based on load characteristics such as constant versus quadratic torque. It then describes various electrical braking methods available in drives, including motor flux braking, braking choppers with resistors, and IGBT regeneration units. The guide concludes by comparing the life cycle costs of different braking solutions.
This document provides an overview of harmonics with AC drives, including:
- Chapters discuss harmonic distortion sources and effects, calculation methods using DriveSize software, and standards for harmonic limits.
- DriveSize is used to model a network supplying a frequency converter and motor load, calculating the harmonic currents and voltages.
- Standards discussed include EN61800-3, IEC1000-2-2, IEC1000-2-4, IEC1000-3-2, IEC1000-3-4, and IEEE519, which set limits on harmonic distortion.
- Methods for reducing harmonics are examined, including rectifier configuration, use of inductors, and passive or active filters
This technical guide book provides 10 chapters that explain different aspects of variable speed drive technology, with a focus on Direct Torque Control (DTC). Chapter 1 introduces DTC and outlines the guide. Chapter 2 discusses the evolution of variable speed drives from early DC motor drives to modern DTC. It compares features and performance of different technologies. Chapter 3 addresses common questions about DTC performance and operation.
This technical guide discusses bearing currents in modern AC drive systems. High frequency bearing currents are generated through three main mechanisms: circulating currents induced by asymmetric capacitive currents in large motors; shaft grounding currents from voltage increases along impedance paths; and capacitive discharge currents from internal voltage divisions in small motors. Proper grounding, motor cabling, and bonding connections are necessary to prevent damage from these high frequency currents flowing through motor bearings. Specialized measurement may be needed to analyze bearing currents.
This technical guide provides information to help ensure electromagnetic compatibility (EMC) compliance when installing and configuring power drive systems (PDS). It defines key EMC terms and concepts. It describes EMC solutions related to emissions, filtering, cabling, and installation practices. Practical examples of EMC-compliant installations are also provided. The guide is intended to assist original equipment manufacturers, system integrators, and panel builders in meeting EMC directive requirements when incorporating drives and auxiliary components into their own systems.
This document provides an overview of functional safety and the requirements of the Machinery Directive. It discusses safety systems for machinery that monitor operations and ensure safe functioning. The document is divided into three parts that cover the theory of functional safety, standards related to the Machinery Directive, and steps for meeting the Directive's requirements. Ensuring functional safety helps prevent accidents and injury while allowing for productivity. The Machinery Directive defines essential health and safety requirements that machinery in the EU must fulfill.
Matlab simulation on chopper based speed control of dc motor: A ReviewIRJET Journal
This document summarizes a literature review on MATLAB simulation of chopper-based speed control of a DC motor. It describes how the speed of a DC motor below rated speed can be controlled by varying the armature voltage using a chopper converter in a closed-loop control system with a PI controller. The review covers DC chopper circuits, separately excited DC motors, modeling a DC motor drive system in MATLAB Simulink with a PI speed controller, and conclusions on simulating speed control of a DC motor using a chopper.
Analysis of Induction Motor Speed Control Using SCADA Based Drive Operated Sy...IJSRD
This document analyzes induction motor speed control using a variable frequency drive (VFD) system operated by a programmable logic controller (PLC) and supervisory control and data acquisition (SCADA) system. It describes how a VFD can be used to efficiently control the speed of a three-phase induction motor and provide energy savings compared to direct connection to the main supply. A PLC is used to control the VFD based on inputs from proximity sensors on a conveyor belt. A SCADA system allows for remote monitoring and control of the motor speed through the PLC and VFD from a computer interface. The system provides flexible and efficient control of induction motor speed for applications requiring variable speed operation like conveyor belts
This document provides an overview of direct torque control (DTC) technology, which is described as the most advanced AC drive technology. It discusses the evolution of variable speed drives from early DC motor drives to modern AC drives that use frequency control, flux vector control, and finally DTC. DTC directly controls motor torque and flux without requiring a modulator or feedback device, providing faster torque response than other drive technologies. The document compares different drive technologies and explains the advantages of DTC in meeting industry demands for better product quality, reduced downtime, fewer required products, and a more comfortable working environment.
The document provides information on AC drives from CG Drives, including their advantages, basic principles of operation, operating modes, braking types, and models. It discusses constant torque and variable torque loads, open loop V/F and vector control modes, closed loop vector control using feedback, and dynamic, DC injection, and regenerative braking methods. It also introduces the CG Drive-SK and CG Drive-SG product lines, specifying their features, connections, dimensions, and optional additions.
This document presents a project report on simulating automatic speed control of a DC drive. It was submitted by four students to fulfill the requirements of a Bachelor of Technology degree. The report includes an introduction to the project, descriptions of the key components used including the DC motor, H-bridge, PWM, and sensors. It also provides the specifications of the components in the Simulink model, discusses the applications of the drive on different loads, and presents the simulation results. The conclusions discuss the advantages of the automatic speed control drive and potential future applications.
This document discusses different types of control for AC drives that use pulse width modulation (PWM) techniques. It describes Volts/Hertz control, Sensorless Vector Control, Flux Vector Control, and Field Oriented Control. Volts/Hertz control provides basic speed control but performance decreases at low speeds. Sensorless Vector Control improves low speed operation and torque control over Volts/Hertz. Flux Vector Control further improves dynamic response but still relies on Volts/Hertz control. Field Oriented Control independently controls motor flux and torque for the best speed and torque regulation, providing "DC-like" performance from AC motors.
Direct torque control (DTC) is an innovative motor control technique developed by ABB that provides superior torque response and accuracy compared to other variable speed drive methods. DTC directly controls motor torque and flux instead of motor currents. It eliminates delays from modulation stages, allowing control dynamics close to theoretical maximums. DTC provides 100% torque from zero speed, high static and dynamic accuracy, and no need for position sensors in most applications. Measurements show DTC enables servo-class performance for induction, permanent magnet, and synchronous reluctance motors.
IRJET- Vector Control of Three Phase Induction MotorIRJET Journal
This document discusses vector control of a three-phase induction motor. Vector control, also called field-oriented control, allows independent control of torque and flux in induction motors, similar to DC motors. The document describes:
1) How vector control works by transforming stator currents into orthogonal d-q components representing flux and torque.
2) The principle of field-oriented control which locks the d-q reference frame to the rotor flux vector for decoupled control of flux and torque.
3) The simulation model built in MATLAB/Simulink to test vector control, including blocks for Clarke/Park transformations, current control, and a PI speed controller.
Simulation and speed control of induction motor drivesPANKAJVERMA315
This document discusses speed control methods for induction motors. It first describes that induction motors are widely used due to their reliability and robustness, but do not inherently have variable speed capability. Recent developments in induction motor speed control, such as constant V/f control, have enabled their use in electrical drives. Constant V/f control maintains a constant voltage-to-frequency ratio to keep the magnetic flux and maximum torque constant at different speeds. The document then examines transients during induction motor starting for different parameters like stator inductance, rotor resistance, and stator resistance. Finally, it analyzes various speed control methods like variable rotor resistance, variable stator voltage, constant V/f control, and vector control.
BLDC Motor Performance & Endurance Test Set up, consist Various types of Dynamometers & Control configurations as Manual Torque Control, PLC Controlled, PC Based Data Acquisition.
BLDC Motors, as they are compact in size, lighter in weight & Most Efficient than other Electric Motors, They are used as Hub Motor Electric Vehicles –Scooters, Electric Bicycle, BLDC Shafted Motors for Solar Power Submersible Pumps, Sump Pumps, for various applications in Automotive, Aerospace, Military, Medical, Lifts, Cranes, Elevators,
Air Condition & Refrigerator Compressors, Fans, Cleaners-Scrubbers, Sweepers, Lawn movers, Trade mills & fitness equipments & many more applications.
Dynamometers employed to test motors are:
Powder Dynamometers, Eddy Current dynamometers, Tandem Dynamometers, AC Regenerative dynamometers,
DC regenerative dynamometers.
Our Proprietary APPSYS MOTOR TEST software developed, using National Instruments LabView Platform, for BLDC Motor test, to monitor & display Motor Electrical Input Power, Mechanical Output Power,Motor Efficiency, Input Voltage, Current, Power Factor, Motor No Load Current, Full Load Current,No Load & Full Load Speed, No Load & Full Load Torque,Motor temperature, Bearing temperature, Winding temperature, etc.
PC based Motor test set up consist: Window XP /Win7 operating systems, PC hardware & PCI Data Card with necessary Digital & Analogueinputs & outputs, Power analyzer, Electrical Input Power (Motor Power Sensor to sense Motor Power -To monitor Motorelectrical Input Power & for Calculation of efficiency) & Mechanical Output Power –Speed &Torque, Efficiency are displayed on Monitor & stored in tabular form &graphs in MS Excel format.
PC Auto & PC Manual mode selector Soft push button switch on Monitorscreen. In PC Auto mode, Data is captured on predetermined (Site settable) time & Torque Loading in 100 steps (independently settable), whereas in PCManual mode –Data is captured manually by pressing data capture soft buttonon screen. Captured data is exported to MS Excel in Table forms & inGraphs form to showTorque-Speed characteristics, Torque-Current and Speed-Current, Efficiency characteristics,Torque-Speed Oscillations at steady stateTorque at different temperatures, Temp measurements etc.& custom characteristics required by clients.
Accessories such as Motor Temperature, Winding Temperature measurements, Motors mounting Test bed, Test Stands with T slot having X, Y & Z adjustment for Length, Width & Height adjustments is also offered along with dynamometer
Direct torque control of induction motor using space vector modulationIAEME Publication
This document discusses direct torque control of an induction motor using space vector modulation. It begins with introducing direct torque control as an alternative to field oriented control for controlling torque and flux directly and independently. It then provides details on the principles of vector control and direct torque control in stator reference frames. The document describes the modeling of an induction motor and simulations performed in MATLAB to validate the direct torque control approach. The simulations demonstrate control of speed, torque, and flux under different gain settings of the PI controller.
Speed control of three phase im by vf open and close loop methodeSAT Journals
This document presents a simulation of speed control for a three-phase induction motor using open-loop and closed-loop V/F control methods. In the open-loop method, a PWM inverter drives the motor and the torque is observed to remain constant with varying rotor speed. In the closed-loop method, a PI controller provides feedback to vary the supply frequency to maintain a constant V/F ratio. Simulation results in MATLAB Simulink show that closed-loop control provides superior speed regulation compared to the open-loop method.
Stepper Motor Drive For Position Control in Robotic Applicationsijiert bestjournal
This project is about making an embedded system in order to control different functionalities of a stepper motor. The main functi ons of this stepper motor are to control the speed and direction. This system will actually adapt the requirements o f the modern technology. With the help of this system one can control the speed of th e stepper motor controller for pick and place robot which is used in material hand ling in various industries.
1) The document discusses the importance of energy conservation in cement processing and describes several key pieces of equipment used in cement production like crushers, separators, conveyors, mills, and fans.
2) It explains how variable frequency drives can provide significant energy savings when used to control the speed of large electric motors that power industrial fans and pumps. This is because the power required by the motor is proportional to the cube of the speed.
3) The document provides a case example of a Mexican cement plant that saved over 5,300 MWh/year in energy and reduced maintenance costs by 97% by replacing the damper fan control of two large induced draft fans with variable frequency drives.
The document describes the design and implementation of a field programmable gate array (FPGA) based speed control system for a brushless direct current (BLDC) motor. It first discusses the motivation and objectives, providing an overview of BLDC motors and advantages of FPGA controllers. It then presents the simulated and experimental setup, which involves a PI speed controller generating PWM signals to control the motor speed through a 3-phase inverter in closed loop. Simulation and experimental results demonstrate that the FPGA-based closed loop controller improves transient and steady-state speed response compared to an open loop configuration.
Vector control is a more advanced and precise method of controlling AC induction motors compared to scalar control. It involves transforming the motor currents and voltages into a rotating reference frame to obtain decoupled control similar to a DC motor. This allows for independent control of flux and torque for faster dynamic response and better performance than scalar control. The basic implementation of vector control uses Clarke and Park transformations to convert between stationary and rotating reference frames in the controller. It provides DC motor-like precision in speed and torque control of induction motors.
Simulation of Direct Torque Control of Induction motor using Space Vector Mo...IJMER
This document presents a simulation of direct torque control (DTC) of an induction motor using space vector modulation (SVM). It begins with an introduction to DTC and its advantages over field oriented control. It then describes the induction motor model and equations used in the simulation. The paper explains the DTC-SVM scheme, including flux and torque estimation, hysteresis controllers, voltage vector selection, and the simulation developed in MATLAB. The results show uniform torque production with reduced ripple compared to without DTC control. In conclusion, DTC-SVM provides improved dynamic performance over conventional DTC.
BLDC motor control reference design press presentationSilicon Labs
This document introduces a brushless DC motor control reference design from Silicon Labs that uses their C8051F850 MCU. It includes all the hardware needed to control a sensorless BLDC motor, including an MCU board, power electronics board, and motor. The reference design provides production-ready firmware that can spin a 2-pole motor at 200,000 RPM. It aims to accelerate customer motor control designs with the high performance 8-bit C8051F850 MCU and includes all documentation, source code, and a GUI for real-time motor control and monitoring.
Speed Control of DC Motor using MicrocontrollerSudip Mondal
This document discusses a project to control the speed of a DC motor using a microcontroller and pulse width modulation. Specifically, it aims to vary the speed-torque relationship of a DC motor electronically using a microcontroller to generate high and low pulses that control motor speed. Pulse width modulation is identified as a technique that can be used to simulate variable voltages through variations in pulse width to achieve variable analog speed control. The document outlines the components used, including an H-bridge circuit and microcontroller, and discusses some limitations such as susceptibility to electromagnetic interference.
This document discusses variable speed drives (VSDs), which are electronic devices that control the speed and torque of electric motors. It describes how VSDs work by rectifying AC power to DC, conditioning it, and inverting it back to variable frequency AC to control motor speed. The document outlines different applications of VSDs for fans, pumps, and other loads and how they provide benefits like energy savings and process control compared to traditional constant speed control methods. It also notes some limitations of VSDs and provides references for further information.
Unlocking the Innovation Hidden within Today’s Variable-Speed DrivesEMEX
It is more than 40 years since the technology of variable-speed drives (VSDs) entered the market. Yet despite electric motors accounting for some 65 percent of industrial energy consumption, only 5 percent of installed motors are speed controlled. While not all motors are suitable for speed control, there is still a large proportion that could be. Yet when asked what is the most effective way to reduce energy, UK business responded with “change energy supplier”. Without doubt the most effective way to get real energy savings is to install energy efficient motors and VSDs. In this presentation John Guthrie looks at the impact of VSDs on a diverse range of sectors, offering real examples from hospitals and swimming pools to data centres and car parks.
Matlab simulation on chopper based speed control of dc motor: A ReviewIRJET Journal
This document summarizes a literature review on MATLAB simulation of chopper-based speed control of a DC motor. It describes how the speed of a DC motor below rated speed can be controlled by varying the armature voltage using a chopper converter in a closed-loop control system with a PI controller. The review covers DC chopper circuits, separately excited DC motors, modeling a DC motor drive system in MATLAB Simulink with a PI speed controller, and conclusions on simulating speed control of a DC motor using a chopper.
Analysis of Induction Motor Speed Control Using SCADA Based Drive Operated Sy...IJSRD
This document analyzes induction motor speed control using a variable frequency drive (VFD) system operated by a programmable logic controller (PLC) and supervisory control and data acquisition (SCADA) system. It describes how a VFD can be used to efficiently control the speed of a three-phase induction motor and provide energy savings compared to direct connection to the main supply. A PLC is used to control the VFD based on inputs from proximity sensors on a conveyor belt. A SCADA system allows for remote monitoring and control of the motor speed through the PLC and VFD from a computer interface. The system provides flexible and efficient control of induction motor speed for applications requiring variable speed operation like conveyor belts
This document provides an overview of direct torque control (DTC) technology, which is described as the most advanced AC drive technology. It discusses the evolution of variable speed drives from early DC motor drives to modern AC drives that use frequency control, flux vector control, and finally DTC. DTC directly controls motor torque and flux without requiring a modulator or feedback device, providing faster torque response than other drive technologies. The document compares different drive technologies and explains the advantages of DTC in meeting industry demands for better product quality, reduced downtime, fewer required products, and a more comfortable working environment.
The document provides information on AC drives from CG Drives, including their advantages, basic principles of operation, operating modes, braking types, and models. It discusses constant torque and variable torque loads, open loop V/F and vector control modes, closed loop vector control using feedback, and dynamic, DC injection, and regenerative braking methods. It also introduces the CG Drive-SK and CG Drive-SG product lines, specifying their features, connections, dimensions, and optional additions.
This document presents a project report on simulating automatic speed control of a DC drive. It was submitted by four students to fulfill the requirements of a Bachelor of Technology degree. The report includes an introduction to the project, descriptions of the key components used including the DC motor, H-bridge, PWM, and sensors. It also provides the specifications of the components in the Simulink model, discusses the applications of the drive on different loads, and presents the simulation results. The conclusions discuss the advantages of the automatic speed control drive and potential future applications.
This document discusses different types of control for AC drives that use pulse width modulation (PWM) techniques. It describes Volts/Hertz control, Sensorless Vector Control, Flux Vector Control, and Field Oriented Control. Volts/Hertz control provides basic speed control but performance decreases at low speeds. Sensorless Vector Control improves low speed operation and torque control over Volts/Hertz. Flux Vector Control further improves dynamic response but still relies on Volts/Hertz control. Field Oriented Control independently controls motor flux and torque for the best speed and torque regulation, providing "DC-like" performance from AC motors.
Direct torque control (DTC) is an innovative motor control technique developed by ABB that provides superior torque response and accuracy compared to other variable speed drive methods. DTC directly controls motor torque and flux instead of motor currents. It eliminates delays from modulation stages, allowing control dynamics close to theoretical maximums. DTC provides 100% torque from zero speed, high static and dynamic accuracy, and no need for position sensors in most applications. Measurements show DTC enables servo-class performance for induction, permanent magnet, and synchronous reluctance motors.
IRJET- Vector Control of Three Phase Induction MotorIRJET Journal
This document discusses vector control of a three-phase induction motor. Vector control, also called field-oriented control, allows independent control of torque and flux in induction motors, similar to DC motors. The document describes:
1) How vector control works by transforming stator currents into orthogonal d-q components representing flux and torque.
2) The principle of field-oriented control which locks the d-q reference frame to the rotor flux vector for decoupled control of flux and torque.
3) The simulation model built in MATLAB/Simulink to test vector control, including blocks for Clarke/Park transformations, current control, and a PI speed controller.
Simulation and speed control of induction motor drivesPANKAJVERMA315
This document discusses speed control methods for induction motors. It first describes that induction motors are widely used due to their reliability and robustness, but do not inherently have variable speed capability. Recent developments in induction motor speed control, such as constant V/f control, have enabled their use in electrical drives. Constant V/f control maintains a constant voltage-to-frequency ratio to keep the magnetic flux and maximum torque constant at different speeds. The document then examines transients during induction motor starting for different parameters like stator inductance, rotor resistance, and stator resistance. Finally, it analyzes various speed control methods like variable rotor resistance, variable stator voltage, constant V/f control, and vector control.
BLDC Motor Performance & Endurance Test Set up, consist Various types of Dynamometers & Control configurations as Manual Torque Control, PLC Controlled, PC Based Data Acquisition.
BLDC Motors, as they are compact in size, lighter in weight & Most Efficient than other Electric Motors, They are used as Hub Motor Electric Vehicles –Scooters, Electric Bicycle, BLDC Shafted Motors for Solar Power Submersible Pumps, Sump Pumps, for various applications in Automotive, Aerospace, Military, Medical, Lifts, Cranes, Elevators,
Air Condition & Refrigerator Compressors, Fans, Cleaners-Scrubbers, Sweepers, Lawn movers, Trade mills & fitness equipments & many more applications.
Dynamometers employed to test motors are:
Powder Dynamometers, Eddy Current dynamometers, Tandem Dynamometers, AC Regenerative dynamometers,
DC regenerative dynamometers.
Our Proprietary APPSYS MOTOR TEST software developed, using National Instruments LabView Platform, for BLDC Motor test, to monitor & display Motor Electrical Input Power, Mechanical Output Power,Motor Efficiency, Input Voltage, Current, Power Factor, Motor No Load Current, Full Load Current,No Load & Full Load Speed, No Load & Full Load Torque,Motor temperature, Bearing temperature, Winding temperature, etc.
PC based Motor test set up consist: Window XP /Win7 operating systems, PC hardware & PCI Data Card with necessary Digital & Analogueinputs & outputs, Power analyzer, Electrical Input Power (Motor Power Sensor to sense Motor Power -To monitor Motorelectrical Input Power & for Calculation of efficiency) & Mechanical Output Power –Speed &Torque, Efficiency are displayed on Monitor & stored in tabular form &graphs in MS Excel format.
PC Auto & PC Manual mode selector Soft push button switch on Monitorscreen. In PC Auto mode, Data is captured on predetermined (Site settable) time & Torque Loading in 100 steps (independently settable), whereas in PCManual mode –Data is captured manually by pressing data capture soft buttonon screen. Captured data is exported to MS Excel in Table forms & inGraphs form to showTorque-Speed characteristics, Torque-Current and Speed-Current, Efficiency characteristics,Torque-Speed Oscillations at steady stateTorque at different temperatures, Temp measurements etc.& custom characteristics required by clients.
Accessories such as Motor Temperature, Winding Temperature measurements, Motors mounting Test bed, Test Stands with T slot having X, Y & Z adjustment for Length, Width & Height adjustments is also offered along with dynamometer
Direct torque control of induction motor using space vector modulationIAEME Publication
This document discusses direct torque control of an induction motor using space vector modulation. It begins with introducing direct torque control as an alternative to field oriented control for controlling torque and flux directly and independently. It then provides details on the principles of vector control and direct torque control in stator reference frames. The document describes the modeling of an induction motor and simulations performed in MATLAB to validate the direct torque control approach. The simulations demonstrate control of speed, torque, and flux under different gain settings of the PI controller.
Speed control of three phase im by vf open and close loop methodeSAT Journals
This document presents a simulation of speed control for a three-phase induction motor using open-loop and closed-loop V/F control methods. In the open-loop method, a PWM inverter drives the motor and the torque is observed to remain constant with varying rotor speed. In the closed-loop method, a PI controller provides feedback to vary the supply frequency to maintain a constant V/F ratio. Simulation results in MATLAB Simulink show that closed-loop control provides superior speed regulation compared to the open-loop method.
Stepper Motor Drive For Position Control in Robotic Applicationsijiert bestjournal
This project is about making an embedded system in order to control different functionalities of a stepper motor. The main functi ons of this stepper motor are to control the speed and direction. This system will actually adapt the requirements o f the modern technology. With the help of this system one can control the speed of th e stepper motor controller for pick and place robot which is used in material hand ling in various industries.
1) The document discusses the importance of energy conservation in cement processing and describes several key pieces of equipment used in cement production like crushers, separators, conveyors, mills, and fans.
2) It explains how variable frequency drives can provide significant energy savings when used to control the speed of large electric motors that power industrial fans and pumps. This is because the power required by the motor is proportional to the cube of the speed.
3) The document provides a case example of a Mexican cement plant that saved over 5,300 MWh/year in energy and reduced maintenance costs by 97% by replacing the damper fan control of two large induced draft fans with variable frequency drives.
The document describes the design and implementation of a field programmable gate array (FPGA) based speed control system for a brushless direct current (BLDC) motor. It first discusses the motivation and objectives, providing an overview of BLDC motors and advantages of FPGA controllers. It then presents the simulated and experimental setup, which involves a PI speed controller generating PWM signals to control the motor speed through a 3-phase inverter in closed loop. Simulation and experimental results demonstrate that the FPGA-based closed loop controller improves transient and steady-state speed response compared to an open loop configuration.
Vector control is a more advanced and precise method of controlling AC induction motors compared to scalar control. It involves transforming the motor currents and voltages into a rotating reference frame to obtain decoupled control similar to a DC motor. This allows for independent control of flux and torque for faster dynamic response and better performance than scalar control. The basic implementation of vector control uses Clarke and Park transformations to convert between stationary and rotating reference frames in the controller. It provides DC motor-like precision in speed and torque control of induction motors.
Simulation of Direct Torque Control of Induction motor using Space Vector Mo...IJMER
This document presents a simulation of direct torque control (DTC) of an induction motor using space vector modulation (SVM). It begins with an introduction to DTC and its advantages over field oriented control. It then describes the induction motor model and equations used in the simulation. The paper explains the DTC-SVM scheme, including flux and torque estimation, hysteresis controllers, voltage vector selection, and the simulation developed in MATLAB. The results show uniform torque production with reduced ripple compared to without DTC control. In conclusion, DTC-SVM provides improved dynamic performance over conventional DTC.
BLDC motor control reference design press presentationSilicon Labs
This document introduces a brushless DC motor control reference design from Silicon Labs that uses their C8051F850 MCU. It includes all the hardware needed to control a sensorless BLDC motor, including an MCU board, power electronics board, and motor. The reference design provides production-ready firmware that can spin a 2-pole motor at 200,000 RPM. It aims to accelerate customer motor control designs with the high performance 8-bit C8051F850 MCU and includes all documentation, source code, and a GUI for real-time motor control and monitoring.
Speed Control of DC Motor using MicrocontrollerSudip Mondal
This document discusses a project to control the speed of a DC motor using a microcontroller and pulse width modulation. Specifically, it aims to vary the speed-torque relationship of a DC motor electronically using a microcontroller to generate high and low pulses that control motor speed. Pulse width modulation is identified as a technique that can be used to simulate variable voltages through variations in pulse width to achieve variable analog speed control. The document outlines the components used, including an H-bridge circuit and microcontroller, and discusses some limitations such as susceptibility to electromagnetic interference.
This document discusses variable speed drives (VSDs), which are electronic devices that control the speed and torque of electric motors. It describes how VSDs work by rectifying AC power to DC, conditioning it, and inverting it back to variable frequency AC to control motor speed. The document outlines different applications of VSDs for fans, pumps, and other loads and how they provide benefits like energy savings and process control compared to traditional constant speed control methods. It also notes some limitations of VSDs and provides references for further information.
Unlocking the Innovation Hidden within Today’s Variable-Speed DrivesEMEX
It is more than 40 years since the technology of variable-speed drives (VSDs) entered the market. Yet despite electric motors accounting for some 65 percent of industrial energy consumption, only 5 percent of installed motors are speed controlled. While not all motors are suitable for speed control, there is still a large proportion that could be. Yet when asked what is the most effective way to reduce energy, UK business responded with “change energy supplier”. Without doubt the most effective way to get real energy savings is to install energy efficient motors and VSDs. In this presentation John Guthrie looks at the impact of VSDs on a diverse range of sectors, offering real examples from hospitals and swimming pools to data centres and car parks.
Practical Variable Speed Drives for Instrumentation and Control SystemsLiving Online
It is estimated that electrical drives and other rotating equipment consume about 50% of the total electrical energy generated in the world today. Other estimates are that pumps, fans, blowers and compressors consume as much as 65% of this total, a large proportion of these applications are powered by fixed or constant speed drivers whose load demands often fluctuate. This poor match of speed and demand results in considerable wasted energy and significantly increased wear of system components.
Variable speed drive technology is a cost effective method to match driver speed to load demands and is an excellent opportunity to reduce operating costs and improve overall efficiencies in your application.
This workshop gives you a fundamental understanding of the installation, operation and troubleshooting of variable speed drives. Typical practical applications of VSDs in process control and materials handling, such as those for pumping, ventilation, conveyers, compressors and hoists are covered in detail. You will learn the basic setup of parameters, control wiring and safety precautions in installing a VSD. The various drive features such as operating modes, braking types, automatic restart and many others will be discussed in detail. You will learn the four basic requirements for a VSD to function properly with emphasis on typical controller faults, their causes and how they can be repaired.
The concluding section of the workshop gives you the fundamental tools in troubleshooting VSDs confidently and effectively.
Even though the focus of the workshop is on the direct application of this technology, you will also gain a thorough understanding of the problems that can be introduced by VSDs such as harmonics, electrostatic discharge and EMC/EMI problems.
MORE INFORMATION: http://www.idc-online.com/content/practical-variable-speed-drives-instrumentation-and-control-systems-38
This document discusses basic instrumentation concepts and components. It defines instrumentation and process control, and describes their functions. It also covers common process measurements like temperature, pressure, flow, and level. For each it discusses units of measurement, measurement elements and principles, and examples of measurement devices. Finally, it briefly introduces how instrumentation signals are transmitted from field devices to control systems.
Various Electric Motors and comparisonDon't Search
It's all about comparison of various types of motors, their working principle, uses, advantages and disadvantages. Presentation on motors, Electric motors.
Advantages and Disadvatages of AC/DC MotorFika Khamis
Simple explanation on advantages and disadvantages of AC and DC motor. Focusing on main point only since the slides is for presentation. Originally design by me.
This document provides information about different types of DC motors and their components and functioning. It discusses separately excited DC motors, shunt DC motors, series DC motors and compound DC motors. It describes the torque-speed characteristics and speed control methods for separately excited and shunt DC motors. The document also mentions induction motors, synchronous motors, single phase and three phase induction motors. It discusses concepts like magnetic field, current, Fleming's left hand rule and losses in AC machines.
Rotor Resistance Control of Wound Rotor Induction Generator (WRIG) using PSCA...Anmol Dwivedi
This document describes the modeling and simulation of a variable slip (type 2) wind turbine using a wound rotor induction generator in PSCAD/EMTDC. Key aspects modeled include the turbine aerodynamics, mechanical drive train, induction generator, and rotor resistance control system. Simulation results over different test cases demonstrate the system operating over a wide speed range and optimally extracting power from the wind by varying the rotor resistance of the induction generator.
Session 03 - History of Automation and Process IntroductionVidyaIA
In this session you will learn:
History of Industrial Automation
Types of Industrial Automation
Process Industries
Overview of Continuous & Batch Process
In this session you will learn:
History of Industrial Automation
Types of Industrial Automation
Process Industries
Overview of Continuous & Batch Process
For more information, visit: https://www.mindsmapped.com/courses/industrial-automation/complete-training-on-industrial-automation-for-beginners/
The document is a technical guide book that provides an overview of direct torque control (DTC) technology for variable speed drives. It begins with an introduction to DTC and its purpose before summarizing the evolution of variable speed drive technology from early DC motor drives to the development of DTC. The guide traces four milestones: DC motor drives, AC drives using frequency control with PWM, AC drives using flux vector control with PWM, and the latest development of AC drives using direct torque control. DTC provides direct control of motor torque without the need for position sensors, offering faster torque response than previous technologies. The guide highlights the advantages of DTC over other approaches.
The document is a technical guide book that provides an overview of direct torque control (DTC) technology for variable speed drives. It discusses the evolution of variable speed drives from early DC motor drives to modern AC drives that use DTC. DC drives provided accurate and fast torque control but required regular maintenance. Early AC drives used simple frequency control which was low cost but lacked torque control accuracy. More advanced flux vector control for AC drives improved torque response but required position feedback devices, making the drives more complex and costly. DTC technology provides torque control comparable to DC drives without position feedback, using only motor parameters to directly control torque. DTC offers faster torque response than any other drive technology.
The document is a technical guide book that provides an overview of direct torque control (DTC) technology for variable speed drives. It begins with an introduction to DTC and its purpose before summarizing the evolution of variable speed drive technology from early DC motor drives to the development of DTC. The guide traces four milestones: DC motor drives, AC drives using frequency control with PWM, AC drives using flux vector control with PWM, and the latest development of AC drives using direct torque control. DTC provides direct control of motor torque without the need for position sensors, offering faster torque response than previous technologies. The guide highlights the advantages of DTC over other approaches.
The document is a technical guide book that provides an overview of direct torque control (DTC) technology for variable speed drives. It discusses the evolution of variable speed drives from early DC motor drives to modern AC drives that use DTC. DC drives provided accurate and fast torque control but required regular maintenance. Early AC drives used simple frequency control which was low cost but lacked torque control accuracy. More advanced flux vector control for AC drives improved torque response but required position feedback devices, making the drives more complex and costly. DTC technology provides torque control comparable to DC drives but without position feedback, using only motor parameters to directly control torque. DTC offers faster torque response than any other drive technology.
This document provides an overview of three-phase asynchronous motors, including their structure, uses, starting methods, and protection requirements. It discusses the main components of asynchronous motors, such as the stator, rotor, and bearings. Common starting methods include direct-on-line, star-delta, and auto-transformer starting. The document also outlines relevant standards for motor protection and coordination, and definitions for terms like direct-on-line starters, reduced voltage starters, and star-delta starters. Finally, it provides information on ABB equipment and solutions for motor coordination.
This document provides an overview of three-phase asynchronous motors, including their structure, typical applications, starting methods, and coordination of protective devices according to relevant standards. It discusses the main components of asynchronous motors, such as the stator, rotor, and chassis. Common starting methods include direct-on-line, star-delta, auto-transformer, and soft starting. The document also outlines considerations for motor protection and coordination based on standards like IEC 60947, including definitions for motor starters, circuit breakers, and coordination between protective devices.
This document provides an overview of three-phase asynchronous motors, including their structure, protection, starting methods, and ABB's coordination equipment and solutions. It discusses the main motor types, applications, standards, starting methods like star/delta and soft starting. ABB offers motors, coordination devices, and tables to help with selection and coordination of protection based on motor characteristics and duty type. Annexes provide additional details on motor theory, starting time calculation, thermal protection, duty types, and UL coordination standards.
Session 02 - Introduction to Industrial AutomationVidyaIA
This document provides an overview of industrial automation and control systems. It begins with an introduction to different types of industries and their classification as either discrete or process manufacturing. It then discusses industrial automation, describing it as the use of technologies and automatic control devices to operate industrial processes without significant human intervention. The document outlines the advantages of automation, such as improved productivity, quality, safety and information accuracy. It also describes the different levels or layers of an automation system, including the field, control, supervisory and enterprise levels. Finally, it provides an agenda for future training sessions on topics related to industrial automation.
This document provides an introduction to boiler control systems engineering. It begins with an overview of basic boiler components such as the furnace, fans, heat exchangers, drums and piping. It then discusses common control strategies for boilers like feedback control, feedforward control and cascade control. The document provides details on tuning PID controllers and determining control parameters. It is intended to help anyone working with boiler control systems understand the engineering of boiler controls.
The aims of the O&M of Gas Turbines Workshop is to share the experiences of our internationally renowned expert with an aim to prevent such incidents and also to examine the factors and opportunities to increase plant safety, environmental performance. And improve uptime and availability all factors contributing to higher profitability.
The workshop will also examine scheduled maintenance and turnarounds which are opportunities to increase plant safety and environmental performance. By enhancing the mechanical integrity of HPI facilities, operating companies can achieve and maintain higher uptime and equipment availability; all are factors that contribute to higher profitability. Best-of-class companies hold the mindset that reliability programs provide great benefits. Investing in new monitoring and conditioning systems, along with preventive maintenance and inspection programs, can optimize unit and total facility performance.
The development of dry low NOx (DLN) combustors for gas turbines has cut the industry's consumption of water, while dramatically slashing air emissions. Unfortunately, this environmental enhancement has created an engineering challenge: The lean-burning DLN combustors are prone to flame instability, which can cause pressure pulsations large enough to destroy the combustor, launching debris downstream where it annihilates other hot-gas-path components. To detect and correct flame instability before it causes millions of dollars of turbine damage, savvy users have begun to install advanced sensors and robust software that monitor the combustor dynamics in real time.
High dynamics can limit hardware life and/or system operability. Thus, there have been various attempts to control combustion dynamics, to prevent degradation of system performance. There are two basic methods for controlling combustion dynamics in an industrial gas turbine combustion system: passive control and active control. As the name suggests, passive control refers to a system that incorporates certain design features and characteristics to reduce dynamic pressure oscillations. Active control, on the other hand, incorporates a sensor to detect, e.g., pressure fluctuations and to provide a feedback signal.
Which, When suitably processed by a controller, provides an input signal to a control device. The control device in turn operates to reduce the dynamic pressure oscillations. The workshop will examine the factors and the issues associated with combustor dynamics, and technologies like AMFM/CFM.
Benefits ofAttending
• LEARN best and effective practices in operations and maintenance of Gas Turbine Based Power Plants
• LEARN how to write and use SOPs
• IMPROVE your plants’ energy efficiency and availability
• ACHIEVE productive and safe operation
• NETWORK with other power plant professionals
• RECEIVE practical information for your CAPEX and OPEX expenditure budget planning
• LEARN about strategic procurement of High Value Spares and insurance
This document provides an overview of industrial automation and control systems. It begins with an agenda that covers industries and classifications, introduction to industrial automation, and examples of process and discrete manufacturing. It then defines process and discrete industries, and provides examples of a car assembly line and oil refinery. The document introduces industrial automation as using technology and automatic controls to operate industrial processes without human intervention. It covers the advantages of automation including higher productivity, quality and safety. Finally, it describes the layers of an automation system including the field, control, supervisory and production, and information levels.
In this session you will learn:
Self Introduction.
What does control system, industrial automation mean?
What is your expectation from this course?
For more information, visit: https://www.mindsmapped.com/courses/industrial-automation/complete-training-on-industrial-automation-for-beginners/
This document provides guidelines for calculating the energy consumption of air handling units (AHUs). It was prepared by a working group of European AHU manufacturers and experts. The document defines terms and symbols, and describes how to calculate the energy used by various AHU components, including fans, heating/cooling coils, energy recovery devices, and humidification/dehumidification. It provides a standardized method for calculating annual thermal and electrical energy consumption of AHUs based on ambient weather conditions. Annexes include correlation factors for different locations in Europe and sample calculation sheets.
Review on Boiler Control Automation for Sugar IndustriesIRJET Journal
This document discusses boiler automation systems for sugar industries. It begins with an abstract that outlines controlling boiler parameters like steam generation and drum water level using PID controllers and SCADA systems. It then discusses several key boiler parameters that are controlled like drum level, pressures, temperatures, and flows. Upgrading to advanced automation controls is recommended to improve efficiency by minimizing excess air, allowing tighter emissions control, and improving combustion characterization. Automating the control of critical parameters can help ensure efficient and reliable plant operation.
Comparison of different controller strategies for Temperature controlIRJET Journal
This document compares different controller strategies (feedback, feedback with feedforward, and internal model control) for controlling temperature in a heat exchanger system. It describes a heat exchanger system with cold water input and temperature sensor output. The strategies are assessed based on transient response criteria like overshoot and settling time, and error-based criteria like integral of absolute and square errors. The study finds that internal model control outperforms the other strategies for a second-order plus dead time system.
IRJET- Material Removal Rate (MRR) Study in Time Reduction Pneumatic Shaper M...IRJET Journal
This document presents a study comparing the material removal rate (MRR) of a conventional shaper machine to a time reduction pneumatic shaper machine. The pneumatic shaper machine was modified to use the return stroke of the ram as a second cutting stroke by adding a clapper box with an additional cutting tool. Testing showed that the pneumatic shaper achieved a higher MRR of 280.5 mm3/min compared to 240.21 mm3/min for the conventional shaper when machining nylon, demonstrating that reducing machining time through this dual-cutting approach increases production rates by raising MRR.
The document provides guidance on EU Council Directives and their application to adjustable speed electrical power drive systems. It addresses questions about CE marking and what it signifies. CE marking indicates a product complies with applicable EU directives, but does not guarantee quality. The document outlines responsibilities and actions required of different parties in the supply chain, such as manufacturers, machine builders, end users and installers, to ensure compliance. It provides checklists and refers to other sections for more detailed explanations of technical documentation, standards, directives and related terminology.
El documento describe las pruebas de factor de potencia/disipación para evaluar el aislamiento de transformadores de potencia. Estas pruebas eléctricas miden la corriente de fuga en el aislamiento bajo tensión alterna para determinar la capacitancia y el factor de disipación. Los resultados indican el estado del aislamiento y si ha habido cambios debidos a envejecimiento, contaminación u humedad. Se explican los diferentes modos de prueba y la importancia de corregir los resultados por la temperatura para una adecuada interpretación.
The document discusses Megger's Dielectric Oil Test Set product line. It provides details on the applications and customers of oil testing, an overview of the product range and improvements, and how the tests are performed. Key features of the new test sets are highlighted such as their lightweight and durable design, precise electrode gap adjustment, reliable results, easy recording and reporting of test data, and flexibility to update test standards.
El documento presenta el nuevo DET14C y DET24C, pinzas probadoras de tierra digitales fabricadas por Megger. Proporcionan mediciones seguras de resistencia de tierra y corriente hasta 600V. Ofrecen características mejoradas como pantalla retroiluminada, memoria avanzada, larga duración de batería y filtro de ruido. Están diseñados para usos como pruebas en subestaciones, torres de comunicación y sistemas de protección contra rayos.
Este documento presenta la gama de ohmímetros de baja resistencia DLRO10 de Megger. Describe las características y especificaciones de los modelos DLRO10, DLRO10X e DLRO10HD. El DLRO10HD es el modelo más reciente diseñado para condiciones extremas con una carcasa dura, pantalla LCD retroiluminada, batería recargable, conexión a la red eléctrica y cinco modos de prueba. La gama completa ofrece mediciones de resistencia desde 100 microohmios hasta 2500 ohmios con protección de entrada
El documento presenta diferentes técnicas modernas de diagnóstico para transformadores de potencia, incluyendo mediciones de capacitancia y factor de disipación, análisis de respuesta en frecuencia y espectroscopia dieléctrica. Explica la importancia del mantenimiento de transformadores y describe sus principales componentes. Además, analiza en detalle las mediciones de capacitancia y factor de disipación tanto de los arrollamientos como de los bushings.
The document provides information on new insulation resistance testers from Megger, including the MIT515, MIT525, MIT1025, S1-568, and S1-1068 models. It discusses the features and benefits of the new models compared to previous versions, such as increased noise immunity, faster charge times, remote operation via Bluetooth or USB, and improved safety. The document also outlines how the different models are suited to various applications and customer types, with the MIT series targeted towards industrial users and the S1 series aimed at utilities and service companies operating in noisier environments.
Este documento presenta información sobre la espectroscopia dieléctrica en el dominio de la frecuencia (DFR) y su aplicación para el diagnóstico de transformadores de potencia. Explica que la DFR mide la capacitancia y el factor de disipación a diferentes frecuencias para determinar la humedad en el aislamiento de papel y la conductividad del aceite aislante. También describe cómo la respuesta del sistema aislante del transformador es una combinación de las respuestas del aceite y el papel, y cómo la DFR puede usarse para evalu
Este documento trata sobre las pruebas de factor de potencia y factor de disipación que se realizan en transformadores. Explica que estas pruebas aplican tensión alterna para medir la corriente de fuga en el aislamiento eléctrico. También describe los diferentes modos de prueba como UST, GST y GST con guarda, y cómo estas pruebas pueden identificar problemas en el aislamiento como contaminación o deterioro.
La gama DET3 y DET4 ofrece probadores de tierra portátiles con pantalla digital para medir la resistividad del suelo y resistencia de sistemas de tierra. Incluyen características como salida especificada para cumplir con normas de seguridad, función de voltímetro, rechazo de ruido, clasificación IP54 y CATIV 100V, y capacidad para realizar pruebas ART, sin estacas, con frecuencia variable, medición de corriente de tierra y rango de 200kΩ. Están diseñados para aplicaciones de campo y
Este documento presenta información sobre pruebas eléctricas para transformadores de potencia. Explica la necesidad de realizar pruebas para evitar averías, y describe varias pruebas de campo comunes como relación de transformación, resistencia de devanados, corriente de excitación y reactancia de fuga. El objetivo de estas pruebas es diagnosticar posibles defectos y asegurar un funcionamiento confiable de los transformadores.
Este documento presenta información sobre el Código Nacional de Electricidad de Perú. Incluye secciones sobre el objetivo del código, las tensiones normalizadas, normas técnicas de referencia, protección contra rayos, y distancias de seguridad requeridas entre instalaciones eléctricas y establecimientos de gas. El documento proporciona detalles técnicos sobre los requisitos de seguridad para instalaciones eléctricas en Perú.
Batteries -Introduction – Types of Batteries – discharging and charging of battery - characteristics of battery –battery rating- various tests on battery- – Primary battery: silver button cell- Secondary battery :Ni-Cd battery-modern battery: lithium ion battery-maintenance of batteries-choices of batteries for electric vehicle applications.
Fuel Cells: Introduction- importance and classification of fuel cells - description, principle, components, applications of fuel cells: H2-O2 fuel cell, alkaline fuel cell, molten carbonate fuel cell and direct methanol fuel cells.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.
KuberTENes Birthday Bash Guadalajara - K8sGPT first impressionsVictor Morales
K8sGPT is a tool that analyzes and diagnoses Kubernetes clusters. This presentation was used to share the requirements and dependencies to deploy K8sGPT in a local environment.
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
Use PyCharm for remote debugging of WSL on a Windo cf5c162d672e4e58b4dde5d797...shadow0702a
This document serves as a comprehensive step-by-step guide on how to effectively use PyCharm for remote debugging of the Windows Subsystem for Linux (WSL) on a local Windows machine. It meticulously outlines several critical steps in the process, starting with the crucial task of enabling permissions, followed by the installation and configuration of WSL.
The guide then proceeds to explain how to set up the SSH service within the WSL environment, an integral part of the process. Alongside this, it also provides detailed instructions on how to modify the inbound rules of the Windows firewall to facilitate the process, ensuring that there are no connectivity issues that could potentially hinder the debugging process.
The document further emphasizes on the importance of checking the connection between the Windows and WSL environments, providing instructions on how to ensure that the connection is optimal and ready for remote debugging.
It also offers an in-depth guide on how to configure the WSL interpreter and files within the PyCharm environment. This is essential for ensuring that the debugging process is set up correctly and that the program can be run effectively within the WSL terminal.
Additionally, the document provides guidance on how to set up breakpoints for debugging, a fundamental aspect of the debugging process which allows the developer to stop the execution of their code at certain points and inspect their program at those stages.
Finally, the document concludes by providing a link to a reference blog. This blog offers additional information and guidance on configuring the remote Python interpreter in PyCharm, providing the reader with a well-rounded understanding of the process.
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
CHINA’S GEO-ECONOMIC OUTREACH IN CENTRAL ASIAN COUNTRIES AND FUTURE PROSPECTjpsjournal1
The rivalry between prominent international actors for dominance over Central Asia's hydrocarbon
reserves and the ancient silk trade route, along with China's diplomatic endeavours in the area, has been
referred to as the "New Great Game." This research centres on the power struggle, considering
geopolitical, geostrategic, and geoeconomic variables. Topics including trade, political hegemony, oil
politics, and conventional and nontraditional security are all explored and explained by the researcher.
Using Mackinder's Heartland, Spykman Rimland, and Hegemonic Stability theories, examines China's role
in Central Asia. This study adheres to the empirical epistemological method and has taken care of
objectivity. This study analyze primary and secondary research documents critically to elaborate role of
china’s geo economic outreach in central Asian countries and its future prospect. China is thriving in trade,
pipeline politics, and winning states, according to this study, thanks to important instruments like the
Shanghai Cooperation Organisation and the Belt and Road Economic Initiative. According to this study,
China is seeing significant success in commerce, pipeline politics, and gaining influence on other
governments. This success may be attributed to the effective utilisation of key tools such as the Shanghai
Cooperation Organisation and the Belt and Road Economic Initiative.
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
artificial intelligence and data science contents.pptxGauravCar
What is artificial intelligence? Artificial intelligence is the ability of a computer or computer-controlled robot to perform tasks that are commonly associated with the intellectual processes characteristic of humans, such as the ability to reason.
› ...
Artificial intelligence (AI) | Definitio
5. Technical guide No. 4 | Guide to variable speed drives 5
Contents
Chapter 1 - Introduction ............................................................................7
General..............................................................................................7
Chapter 2 - Processes and their requirements ..........................................8
Why variable speed control? ...............................................................8
Industrial segments with VSD processes..............................................9
Variables in processing systems ........................................................10
Machines are used to alter materials’ properties... .............................11
Well defined shape.......................................................................11
Indefinite shape ...........................................................................11
...and to transport materials..............................................................12
Solid materials .............................................................................12
Liquid materials ...........................................................................12
Gaseous materials .......................................................................12
Chapter 3 - The workhorse of industry: the electric motor......................13
Electric motors drive most machines .................................................13
Motors convert electrical energy into mechanical energy ....................14
Frequency converters control electromagnetic induction.....................15
The efficiency of the drive system......................................................16
Reversed rotation or torque is sometimes required.............................17
The load, friction and inertia resist rotation.........................................18
The motor has to overcome the loading torque ..................................19
The drive torque and load torque are equal at nominal speed .............20
Chapter 4 - Variable volumes require some form of control ....................21
Variable material flow and input/output requirements..........................21
Simpler control methods...................................................................22
The best control method is VSD........................................................23
Mechanical, hydraulic and electrical VSDs .........................................24
Hydraulic coupling .......................................................................24
DC drive......................................................................................24
AC drive ......................................................................................24
Electrical VSDs dominate the market .................................................25
Maintenance costs.......................................................................25
Productivity .................................................................................25
Energy saving ..............................................................................25
Higher quality ..............................................................................25
The AC drives market is growing fast.................................................26
Chapter 5 - AC drive: The leading control method ..................................27
The basic functions of an AC drive ....................................................27
A motor’s load capacity curves with an AC drive ................................28
6. 6 Guide to variable speed drives | Technical guide No. 4
AC drive features for better process control .......................................29
Reversing ....................................................................................30
Torque control .............................................................................30
Eliminating mechanical vibrations..................................................30
Power loss ride-through ...............................................................31
Stall function ...............................................................................31
Slip compensation .......................................................................32
Flying start ..................................................................................32
Environmental features.................................................................33
EMC............................................................................................33
Chapter 6 - Cost benefits of AC drives....................................................34
Technical differences between other systems and AC drives...............35
No mechanical control parts needed .................................................36
Factors affecting cost .......................................................................37
Investment costs: mechanical and electrical components ...................38
The motor ...................................................................................38
The AC drive................................................................................38
Installation costs: throttling compared to AC drive..............................39
Operational costs: maintenance and drive energy ..............................40
Total cost comparison ......................................................................41
Chapter 7 - Index.....................................................................................42
7. Technical guide No. 4 | Guide to variable speed drives 7
Chapter 1 - Introduction
General
This guide continues ABB’s technical guide series, describing
different variable speed drives (VSD) and how they are used in
industrial processes. Special attention has been given to electri-
cal VSDs and especially to AC Drives.
The guide tries to be as practical as possible. No special know-
ledge of VSDs is required, although basic technical know-how
is required to fully understand the terms and descriptions used.
8. 8 Guide to variable speed drives | Technical guide No. 4
Chapter 2 - Processes and their
requirements
Why variable speed control?
To understand why variable speed control is necessary, we first
need to understand the requirements of different processes.
These processes can be divided into two main categories;
material treatment and material transport, although there are
many different sub-categories that come under these two basic
headings.
Common to both main categories, however, is the need to be
able to adjust the process. This is accomplished with VSDs.
This chapter describes the main industrial and non-industrial
processes using VSDs.
9. Technical guide No. 4 | Guide to variable speed drives 9
Examples
Industrial:
Chemical industry
Pulp, paper, printing
Food & beverage
Power plants
Mining
Metal industry
Machine shops
Plastics
Textiles
Non-industrial:
HVAC
Water treatment
Industrial segments with VSD processes
Industrial processes are numerous, and the list above mentions
just some of the industrial segments with VSD processes. What
they have in common is that they all require some kind of control
using VSD.
For example, in air conditioning applications (part of HVAC), air
flow requirements change according to the humidity and tem-
perature in the room. These can be met by adjusting the supply
and return air fans. These adjustments are carried out with VSDs.
Fans are also used in power plants and the chemical industry.
In both cases, the fans need to be adjusted according to the
main process. In power plants, the main process changes due
to varying demands for power at different times of the year, day
or week. Likewise, the need for VSDs differs according to the
process.
Processes and their requirements
10. 10 Guide to variable speed drives | Technical guide No. 4
Processes and their requirements
Variables in processing systems
This diagram shows what kinds of variables affect the processing
system. These variables can be divided into energy and mate-
rial variables. In the processing system itself, material or energy
is processed by means of mechanical power, electromagnetic
influence, thermal influence, chemical and biological reactions
or even nuclear power.
Each process needs the material and energy supplied to accom-
plish the required process. The product or final material state is
the output of the process, but in every process, waste, in the
form of energy and/or material, is also produced.
In processing systems, VSDs are used to control the mechanical
power of the different machines involved in the process.
Material treatment can also be controlled by VSDs. A good ex-
ample is a drying kiln, in which the hot air temperature must be
constant. The process is controlled by controlling the speed of
the hot air fans using VSDs.
11. Technical guide No. 4 | Guide to variable speed drives 11
Processes and their requirements
Machines are used to alter materials’ properties...
As mentioned earlier in this guide, working machine processes
can be divided into two categories. The first category is material
treatment, which is accomplished using various types of process-
ing apparatus to alter a material’s properties into another form.
Well defined shape
Processing apparatus can be divided into two groups according
to the resulting shape of the material being treated. The shape
can be either well defined or indefinite. Materials with a well-
defined shape, such as paper, metal and wood, are processed
with machinery. Examples are paper machines, rolling mills and
saw mill lines.
Indefinite shape
Materials with an indefinite shape, such as various food products,
plastics etc., are processed with plant equipment. Examples of
this kind of equipment are margarine stirrers, and different kinds
of centrifuges and extruders.
12. 12 Guide to variable speed drives | Technical guide No. 4
Processes and their requirements
...and to transport materials
The second category consists of machines which transport
material to a desired location. This group consists of conveying,
dosing and pressure changing apparatus. These machines can
be divided into three different sub-groups according to whether
the type of material being treated is a solid, liquid or gas.
Solid materials
Solid materials, such as shipping containers, metal, wood, miner-
als and of course people, are transported by conveying appara-
tus. Such apparatus includes cranes, conveyors and elevators.
Liquid materials
Liquid materials, for example, water, oil or liquid chemicals, are
transported by pumps.
Gaseous materials
Gaseous materials such as air are transported using fans, com-
pressors or blowers. A special application of these machines is
air conditioning.
In the diagram above, five different types of machines are pre-
sented. They either shape or transport different types of material,
but all of them can be potentially used with Variable Speed Drives.
13. Technical guide No. 4 | Guide to variable speed drives 13
Chapter 3 - The workhorse of industry:
the electric motor
All of the machines mentioned earlier in this guide are com-
monly driven by electric motors. It can be said that the electric
motor is the workhorse of industrial processes. In this chapter,
we will take a closer look at electrical motors - especially the
squirrel cage AC motor, which is the most common motor used
in industrial processes.
Electric motors drive most machines
Every machine consists of four different components, shown in
the diagram. These components are energy control, the motor,
transmission and the working machine. Together, the first three
components comprise the so called “drive system”. This drive
system can transform a given type of energy, usually electrical,
into mechanical energy, which is then used by the working ma-
chine. Energy is supplied to the drive system from the power
supply.
In each of the three drive system components, variable speed
control is possible. Variable speed control can be accomplished,
for example, using a frequency converter as the energy control
component, a two speed motor as the motor component and
gears as the transmission component.
As mentioned earlier, most machines are driven by an electric
motor. Electric motors can be divided into AC and DC motors.
AC motors, particularly squirrel cage motors, are the most com-
monly used motors in industrial processes.
14. 14 Guide to variable speed drives | Technical guide No. 4
U
The workhorse of industry: the electric motor
Motors convert electrical energy into mechanical energy
An AC motor’s ability to convert electrical energy into mechani-
cal energy is based on electromagnetic induction. The voltage
in stator windings forms the current and magnetic flux. The di-
rection of this flux can be determined using the right hand rule
from the stator current.
By changing the direction of the voltage in stator windings, the
direction of the flux can also be changed. By changing the volt-
age direction in the three phase motor windings in the correct
order, the magnetic flux of the motor starts to rotate. The motor’s
rotor will then follow this flux with a certain slip. This is the basic
principle used to control AC motors.
This control can be achieved using a frequency converter. As the
name suggests, a frequency converter changes the frequency of
the alternating current and voltage. A frequency converter con-
sists of three parts. Regular 50 Hz 3-phase current is fed in to the
rectifier part, which converts it to direct current. The DC voltage
is fed into the DC bus circuit, which filters the pulsating voltage.
The inverter unit then connects each motor phase either to the
negative or the positive DC bus according to a certain order.
To receive the flux direction shown in the diagram, switches V1,
V4 and V5 should be closed. To make the flux rotate counter-
clockwise, switch V6 has to be closed but V5 has to be open.
If switch V5 is not opened, the circuit will short circuit. The flux
has turned 60° counterclockwise.
15. Technical guide No. 4 | Guide to variable speed drives 15
The workhorse of industry: the electric motor
Frequency converters control electromagnetic induction
There are eight different switching positions in the inverter. In
two positions, the voltage is zero, ie, when all the phases are
connected to the same DC bus, either negative or positive. So
in the remaining six switching positions there is voltage in the
motor windings, and this voltage creates magnetic flux.
The diagram shows these six switching positions and the flux
directions, which the voltage in the windings generates in each
case. Voltage also generates current in the windings, the direc-
tions of which are marked with arrows in each phase.
In practice, control is not quite as simple as presented here.
Magnetic flux generates currents in the rotor. These rotor cur-
rents complicate the situation. External interference, such as
temperature or load changes, can also cause some control dif-
ficulties. Nevertheless, with today’s technology and know-how,
it is possible to effectively deal with interference.
Electrical VSDs also provide many additional benefits, such as
energy savings, because the motor does not use more electrical
energy than required. Furthermore, control is better than with
conventional methods, because electrical VSDs also provide the
possibility for stepless control.
16. 16 Guide to variable speed drives | Technical guide No. 4
The efficiency of the drive system
The total efficiency of the drive system depends on the losses in
the motor and its control. Both drive and motor losses are ther-
mal, so they appear as heat. Input power to the drive system is
electrical in form, while output power is mechanical. That is why
calculating the coefficient of efficiency (η) requires knowledge of
both electrical and mechanical engineering.
Electrical input power Pin
depends on voltage (U), current (I) and
the power factor (cosϕ). The power factor tells us what propor-
tion of the total electric power is active power and how much is
so called reactive power. To produce the required mechanical
power, active power is required. Reactive power is needed to
produce magnetisation in the motor.
Mechanical output power Pout
depends on the required torque
(T) and rotating speed (n). The greater the speed or torque re-
quired, the greater the power required. This has a direct effect
on how much power the drive system draws from the electrical
supply. As mentioned earlier, the frequency converter regulates
the voltage, which is fed to the motor, and in this way directly
controls the power used in the motor as well as in the process
being controlled.
Electrical switching with transistors is very efficient, so the effi-
ciency of the frequency converter is very high, from 0.97 to 0.99.
Motor efficiency is typically between 0.82 and 0.97 depending
on the motor size and its rated speed. So it can be said that
the total efficiency of the drive system is always above 0.8 when
controlled by a frequency converter.
The workhorse of industry: the electric motor
17. Technical guide No. 4 | Guide to variable speed drives 17
Reversed rotation or torque is sometimes required
In some cases, reversed rotation of the motor is required.
In addition, torque direction requirements might change. These
factors combined form the so called “four quadrant drive”. The
name comes from the four different quadrants (I to IV) shown
in the diagram.
I quadrant: In the first quadrant, the motor is rotating clockwise.
Because the torque is in the same direction as the speed, the
drive is accelerating.
II quadrant: In the second quadrant, the motor is still rotating
clockwise, but the torque is in the opposite direction, so the
drive is decelerating.
III & IV quadrants: In the third and fourth quadrant, the motor
is rotating counterclockwise and the drive is again accelerating
or decelerating, depending on the torque direction.
With a frequency converter, torque direction changes can be im-
plemented independent of the direction of rotation. To produce an
efficient four quadrant drive, some kind of braking arrangement
is required. This kind of torque control is especially required in
crane applications, where the rotation direction might change,
but the torque direction remains the same.
The workhorse of industry: the electric motor
18. 18 Guide to variable speed drives | Technical guide No. 4
The load, friction and inertia resist rotation
The motor must produce the required torque to overcome the
load torque. Load torque consists of friction, inertia of the moving
parts and the load itself, which depends on the application. In
the example in the diagram, the motor torque has to be greater
than the load torque, which is dependent on the mass of the
box, if the box is to rise.
Load factors change according to the application. For example,
in a crusher, the load torque is dependent not only on friction
and inertia, but also on the hardness of the crushed material. In
fans and blowers, air pressure changes affect the load torque,
and so on.
The workhorse of industry: the electric motor
19. Technical guide No. 4 | Guide to variable speed drives 19
The motor has to overcome the loading torque
In any case, the loading torque has to be known before select-
ing the motor for the application. The required speed also has
to be known. Only then can a suitable motor be selected for
the application.
If the motor is too small, the requirements cannot be met and
this might lead to serious problems. For example, in crane ap-
plications, a motor that is too small may not be able to lift the
required load quickly enough to the desired height. It might even
drop the load completely, as shown in the diagram. This could
be disastrous for people working at the harbour or site where
this crane would be used. To calculate the rated torque of the
motor the following formula can be used:
T[Nm]=9550 x
P[kW]
n[1/min]
The workhorse of industry: the electric motor
20. 20 Guide to variable speed drives | Technical guide No. 4
The drive torque and load torque are equal at nominal speed
A motor’s torque/speed curve is unique and has to be calculated
for every motor type separately. A typical torque/speed curve is
shown in the graph as Tm
. As can be seen, the maximum load
torque is reached just below nominal speed.
Load torque Tl
usually increases with speed. Depending on the
application it can be linear or quadratic. The motor will auto-
matically accelerate until the load torque and motor torque are
equal. This point is shown on the graph as the intersection of
Tm
and Tl
. Actual torque (Tact
) is shown on the y-axis and actual
speed (nact
) on the x-axis.
These are the principles that govern how an ordinary squirrel
cage motor works. With a frequency converter, optimal control
performance can be obtained from the motor and the whole drive
system. This will be introduced later in this guide.
The workhorse of industry: the electric motor
21. Technical guide No. 4 | Guide to variable speed drives 21
Typical cases
Application Input Interference Output
1 Submersible pump Water level
2 Pump application Water level Water flow
3 FD fan Heat demand Atmospheric pressure
4 Sawmill line Log diameter Hardness of wood
5 Screw conveyor Material volume
6 Feeder Hardness of material Load
7 Grinder Wear of the grind
ProcessInput
Output
Interference
Chapter 4 - Variable volumes require some
form of control
In most processes there is at least one variable. This variable
causes the need for process adjustment. Therefore variable
processes and material volumes need some form of control.
In this chapter we will look at processes and their variables. We
will also examine different control methods.
Variable material flow and input/output requirements
There may be many different parameters involved in a process,
the most common being input, output and interference. These
parameters may need to be constant or they may need to be
changed according to a preset pattern. As discussed in the first
chapter, there are always inputs and outputs present in a process
and, in almost every case, interference as well.
In some processes there is no interference and the input is
constant. This kind of process works without any variable speed
control. However, if the output parameters need to be changed,
the input is variable or there is interference present, then vari-
able speed control might be the solution to fulfilling the process
requirements.
The above table lists some processes in which variable speed
control is required. It also shows the reasons for the control;
input, interference or output.
22. 22 Guide to variable speed drives | Technical guide No. 4
Variable volumes require some form of control
Simpler control methods
There are many simpler control methods in existence such as
throttling or bypass control. The construction of such equip-
ment is usually very simple and the investment may look cost
effective at first.
However, there are many drawbacks. For example the optimal
process capacity, which gives the best quality of the process,
is very difficult to achieve with simple control. An increase in
production capacity usually requires reconstruction of the whole
process and with each direct on-line startup there is a risk of
electrical and/or mechanical damage.
The simple control methods are also energy consuming, so in
addition to the total operating cost being higher than with VSDs,
the environmental effects, such as CO2
emissions from power
plants, also increase. Therefore, the total life-cycle cost of invest-
ment in simple control methods is much higher than with VSDs.
23. Technical guide No. 4 | Guide to variable speed drives 23
Variable volumes require some form of control
The best control method is VSD
The best control method for most systems is VSD. Imagine you
are driving a car for example. If you are driving on a highway and
entering a populated area, you need to reduce speed so that
you don’t risk your own and other peoples’ lives.
The best possible way to do this is of course to reduce motor
rotation speed by taking your foot off the gas pedal and, if nec-
essary, changing to a lower gear. Another possibility would be
to use the same gear, keep your foot on the gas and reduce
speed simply by braking. This would not only cause wear on the
engine and brakes, but also use a lot of fuel and reduce your
overall control of the vehicle. Furthermore, the original goal of
reducing speed without risking your own and other peoples’ lives
would not have been achieved.
24. 24 Guide to variable speed drives | Technical guide No. 4
Mechanical, hydraulic and electrical VSDs
Above are the four most common VSDs in the industrial sec-
tor. Mechanical variable speed control usually uses belt drives,
and is controlled by moving conical pulleys manually or with
positioning motors.
Hydraulic coupling
In hydraulic coupling, the turbine principle is used. By changing the
volume of oil in the coupling, the speed difference between the
driving and driven shafts changes. The oil amount is controlled
with pumps and valves.
DC drive
In the DC drive, a DC converter changes the motor supply volt-
age fed to the DC motor. In the motor, a mechanical inverter, a
commutator, changes direct current to alternating current.
AC drive
In the frequency converter or AC drive, a standard squirrel cage
motor is used, so no mechanical inverters are required. The
speed of the motor is regulated by a frequency converter that
changes the frequency of the motor voltage, as presented earlier
in this guide. The frequency converter itself is controlled with
electrical signals.
The diagram shows the location of the control equipment for
each type of VSD. In mechanical and hydraulic VSDs, the con-
trol equipment is located between the motor and the working
machine, which makes maintenance very difficult.
In electrical VSDs, all control systems are situated in an electri-
cal equipment room and only the driving motor is in the process
area. This is just one benefit of electrical VSDs. Other benefits
are presented on the following page.
Variable volumes require some form of control
25. Technical guide No. 4 | Guide to variable speed drives 25
Electrical VSDs dominate the market
Here are the four most important arguments for using electrical
VSDs, presented along with estimated VSD market shares in
Europe in 2000. The four main benefits of using electrical VSDs
are highlighted at the turning points of the speed curve.
Maintenance costs
Direct on-line starting stresses the motor and also the electrical
equipment. With electrical VSDs, smooth starting is possible and
this has a direct effect on maintenance costs.
Productivity
Process equipment is usually designed to cater for future pro-
ductivity increases. Changing constant-speed equipment to
provide higher production volumes requires money and time.
With the AC drive, speed increases of 5 to 20 percent are not a
problem, and the production increase can be achieved without
any extra investment.
Energy saving
In many processes, production volumes change. Changing
production volumes by mechanical means is usually very inef-
ficient. With electrical VSDs, changing the production volume
can be achieved by changing the motor speed. This saves a lot
of energy particularly in pump and fan applications, because the
shaft power is proportional to the flow rate to the power of three.
Higher quality
The accurate speed control obtainable with electrical VSDs re-
sults in process optimisation. The optimal process control leads
to the best quality end product, which means the best profit for
the customer.
Variable volumes require some form of control
26. 26 Guide to variable speed drives | Technical guide No. 4
Due to these benefits, electrical VSDs are dominating the market,
as can be seen from the table above. AC and DC drives together
account for over 75%, and AC drives for more than 50%, of the
total VSD market in Europe in 2000.
The AC drives market is growing fast
This diagram shows the projected development of the electrical
VSDs market to the year 2000. As can be seen, the AC drives
market is growing at almost 10% per year, which accounts for
the entire growth of the electrical and VSD market. The market
share of DC drives is diminishing, and the total DC market size
remains approximately constant. This progress is due to the
development of AC drives technology.
As presented earlier in this guide, the AC drive has many benefits
over other process control methods. The difference between
the AC and the DC motor is that the DC motor has a mechani-
cal commutator, utilising carbon brushes. These brushes need
regular maintenance and the commutator itself complicates the
motor structure and consumes energy. These are the main rea-
sons why the AC drives market share is growing in comparison
to DC drives.
Variable volumes require some form of control
27. Technical guide No. 4 | Guide to variable speed drives 27
Chapter 5 - AC drive: the leading control
method
Taking into account everything presented so far, we can con-
fidently say that the AC drive is the leading control method. In
the following chapter we will take a closer look at the different
features of the AC drive, and the levels of performance the drive
can offer.
The basic functions of an AC drive
In this diagram, the basic functions of an AC drive are presented.
There are four different components in AC drive motor control.
These components are the user interface, the motor, the electri-
cal supply and the process interface.
An electrical supply feeds the required electricity to the drive;
one selection criteria for the drive is the supply voltage and its
frequency. The AC drive converts the frequency and voltage and
feeds the motor. This conversion process is controlled by signals
from the process or user via the process and user interfaces.
The user interface provides the ability to observe the AC drive
and obtain different process information via the drive. This makes
the drive easy to integrate with other process control equipment
and overriding process control systems.
28. 28 Guide to variable speed drives | Technical guide No. 4
A motor’s load capacity curves with an AC drive
If the motor is driven without a frequency converter, its load
capacity curves cannot be modified. It will produce a speci-
fied torque at certain speed and maximum torque cannot be
exceeded.
With a frequency converter drive, there are different loading op-
tions. The standard curve, Curve 1 in the diagram, can be used
continuously. Other curves can only be used for certain periods
of time, because the motor’s cooling system is not designed for
this kind of heavy use.
These higher load capacity levels might be needed, for example,
during startup. In certain applications, as much as twice the
amount of torque is required when starting. With a frequency con-
verter this is possible, meaning that a motor can be dimensioned
according to its normal use. This reduces the investment cost.
To be able to use these features it is very important that the load,
the AC drive and the motor are compatible. Otherwise the motor
or the converter will overheat and be damaged.
AC drive: the leading control method
29. Technical guide No. 4 | Guide to variable speed drives 29
Important features:
- inputs and outputs
- reversing function
- ramp times acceleration/deceleration
- variable torque V/Hz settings
- torque boosting
- eliminating mechanical vibrations
- load limits to prevent nuisance faults
- power loss ride-through
- stall function
- slip compensation
- flying start
AC drive features for better process control
AC drives also have other internal features and functions which
are sometimes required for better process control. Examples of
these features are listed in the diagram. With inputs and outputs
for example, different kinds of process information can be fed to
the drive and it will control the motor accordingly. Alternatively,
the load can be limited to prevent nuisance faults and to protect
the working machine and the whole drive system.
In the following sections the listed features are presented in
more detail.
AC drive: the leading control method
30. 30 Guide to variable speed drives | Technical guide No. 4
Reversing
Reversing the motor rotation is simple to accomplish with an AC
drive. With ABB’s frequency converters it can be achieved simply
by pressing one button. Furthermore, it is possible to set different
acceleration and deceleration ramp times. The ramp form can
also be modified according to the user’s wishes. In the diagram
(above, left) an S-ramp has been presented. Another possibility
could be a linear ramp.
Torque control
Torque control is relatively simple with an AC drive. Torque
boosting, which was presented earlier, is necessary if a very
high starting torque is required. Variable torque U/f settings
mean that maximum torque can be achieved at a lower speed
of rotation than normal.
Eliminating mechanical vibrations
Mechanical vibrations can be eliminated by by-passing critical
speeds. This means that when a motor is accelerated close to
its critical speed, the drive will not allow the actual speed of
the motor to follow the reference speed. When the critical point
has been passed, the motor will return to the regular curve very
quickly and pass the critical speed.
AC drive: the leading control method
31. Technical guide No. 4 | Guide to variable speed drives 31
Power loss ride-through
The power loss ride-through function is used if the incoming
supply voltage is cut off. In such a situation, the AC drive will
continue to operate using the kinetic energy of the rotating motor.
The drive will be fully operational as long as the motor rotates
and generates energy for the drive.
Stall function
With an AC drive, the motor can be protected in a stall situation
with the stall function. It is possible to adjust supervision limits
and choose how the drive reacts to the motor stall condition. Pro-
tection is activated if three conditions are met at the same time.
1. The drive frequency has to be below the preset stall frequency.
2. The motor torque has to rise to a certain limit, calculated by
the drive software.
3. The final condition is that the motor has been in the stall limit
for longer than the time period set by the user.
AC drive: the leading control method
32. 32 Guide to variable speed drives | Technical guide No. 4
Slip compensation
If the motor load torque is increased, the speed of the motor will
decrease as shown in the diagram (above, left). To compensate
for this slip, the torque/speed curve can be modified with the
frequency converter so that torque increase can be accomplished
with the same speed as previously.
Flying start
The flying start feature is used when a motor is connected to a
flywheel or a high inertia load. The flying start works even without
a speed feedback. In case of rotating motor, the inverter is first
started with a reduced voltage and then synchronised to the
rotating rotor. After synchronised the voltage and the speed are
increased to the corresponding levels.
AC drive: the leading control method
33. Technical guide No. 4 | Guide to variable speed drives 33
Environmental features
Any drive system has to handle different environmental stresses
such as moisture or electrical disturbances. The squirrel cage
motor is very compact and can be used in very hostile condi-
tions. The IP54 degree of protection guarantees that it can work
in a dusty environment and that it can bear sprinkling water from
any direction.
The frequency converter usually has an IP21 degree of protec-
tion. This means that it is not possible to touch the live parts and
that vertically dripping water will not cause any harm. If a higher
degree of protection is required, it can be obtained, for example,
by installing the drive inside a cabinet with the required degree
of protection. In such cases, it is essential to ensure that the
temperature inside the cabinet will not exceed the allowed limits.
EMC
Another important environmental feature is electromagnetic com-
patibility (EMC). It is very important that a drive system fulfills the
EMC directives of the European Union. This means that the drive
system can bear conductive and radiative disturbances, and that
it does not send any conductive or radiative disturbances itself
either to the electrical supply or the surrounding environment.
If you require more information about the EMC directives and
their effects on drives, please refer to ABB’s Technical guide No.
3, EMC Compliant Installation and Configuration for a Power
Drive System.
AC drive: the leading control method
34. 34 Guide to variable speed drives | Technical guide No. 4
Chapter 6 - Cost benefits of AC drives
In addition to their technical advantages, AC drives also provide
many cost benefits. In this chapter, these benefits are reviewed,
with the costs divided into investment, installation and opera-
tional costs.
At the moment there are still plenty of motors sold without vari-
able speed AC drives. This pie chart shows how many motors
below 2.2 kW are sold with frequency converters, and how many
without. Only 3% of motors in this power range are sold each year
with a frequency converter; 97% are sold without an AC drive.
This is astonishing considering what we have seen so far in
this guide. Even more so after closer study of the costs of an AC
drive compared to conventional control methods. But first let’s
review AC drive technology compared to other control methods.
35. Technical guide No. 4 | Guide to variable speed drives 35
Technical differences between other systems and AC drives
AC drive technology is completely different from other, simpler
control methods. It can be compared, for example, to the dif-
ference between a zeppelin and a modern airplane.
We could also compare AC drive technology to the development
from a floppy disk to a CD-ROM. Although it is a simpler infor-
mation storage method, a floppy disk can only handle a small
fraction of the information that a CD-ROM can.
The benefits of both these innovations are generally well known.
Similarly, AC drive technology is based on a totally different
technology to earlier control methods. In this guide, we have
presented the benefits of the AC drive compared to simpler
control methods.
Cost benefits of AC drives
36. 36 Guide to variable speed drives | Technical guide No. 4
Cost benefits of AC drives
No mechanical control parts needed
To make a proper cost comparison, we need to study the con-
figurations of different control methods. Here we have used
pumping as an example. In traditional methods, there is always
a mechanical part and an electrical part.
In throttling you need fuses, contactors and reactors on the
electrical side and valves on the mechanical side. In On/Off
control, the same electrical components are needed, as well as
a pressure tank on the mechanical side. The AC drive provides
a new solution. No mechanics are needed, because all control
is already on the electrical side.
Another benefit, when thinking about cost, is that with an AC
drive we can use a regular 3-phase motor, which is much cheaper
than the single phase motors used in other control methods.
We can still use 220 V single phase supply, when speaking of
power below 2.2 kW.
37. Technical guide No. 4 | Guide to variable speed drives 37
Conventional methods: AC drive:
both electrical and
mechanical parts
all in one
many electrical parts only one electrical component
mechanical parts need regular
maintenance
no mechanical parts, no wear
and tear
mechanical control is energy
consuming
saves energy
Cost benefits of AC drives
Factors affecting cost
This list compares the features of conventional control methods
with those of the AC drive, as well as their effect on costs. In
conventional methods there are both electrical and mechanical
components, which usually have to be purchased separately. The
costs are usually higher than if everything could be purchased
at once.
Furthermore, mechanical parts wear out quickly. This directly
affects maintenance costs and in the long run, maintenance is
a very important cost item. In conventional methods there are
also many electrical components. The installation cost is at least
doubled when there are several different types of components
rather than only one.
And last but not least, mechanical control is very energy consum-
ing, while AC drives practically save energy. This not only helps
reduce costs, but also helps minimise environmental impact by
reducing emissions from power plants.
38. 38 Guide to variable speed drives | Technical guide No. 4
Investment costs: mechanical and electrical components
In this graph, the investment structure as well as the total price of
each pump control method is presented. Only the pump itself is
not added to the costs because its price is the same regardless
of whether it’s used with an AC drive or valves. In throttling, there
are two possibilities depending on whether the pump is used in
industrial or domestic use. In an industrial environment there are
stricter requirements for valves and this increases costs.
The motor
As can be seen, the motor is much more expensive for traditional
control methods than for the AC drive. This is due to the 3-phase
motor used with the AC drive and the single phase motor used
in other control methods.
The AC drive
The AC drive does not need any mechanical parts, which reduces
costs dramatically. Mechanical parts themselves are almost al-
ways less costly than a frequency converter, but electrical parts
also need to be added to the total investment cost.
After taking all costs into account, an AC drive is almost always
the most economical investment, when compared to differ-
ent control methods. Only throttling in domestic use is as low
cost as the AC drive. These are not the total costs, however.
Together with investment costs we need to look at installation
and operational costs.
Cost benefits of AC drives
39. Technical guide No. 4 | Guide to variable speed drives 39
Throttling AC drive
Installation material 20 USD 10 USD
Installation work 5h x 65 USD = 1h x 65 USD =
325 USD 65 USD
Commissioning 1h x 65 USD = 1h x 65 USD =
work 65 USD 65 USD
Total 410 USD 140 USD
Savings in installation: 270 USD!
Installation costs: throttling compared to AC drive
Because throttling is the second lowest investment after the AC
drive, we will compare its installation and operating costs to the
cost of the AC drive. As mentioned earlier, in throttling there are
both electrical and mechanical components. This means twice
the amount of installation material is needed.
Installation work is also at least doubled in throttling compared to
the AC drive. To install a mechanical valve into a pipe is not that
simple and this increases installation time. To have a mechanical
valve ready for use usually requires five hours compared to one
hour for the AC drive. Multiply this by the hourly rate charged by
a skilled installer to get the total installation cost.
The commissioning of a throttling-based system does not usu-
ally require more time than commissioning an AC drive based
system. One hour is usually the time required in both cases. So
now we can summarise the total installation costs. As you can
see, the AC drive saves up to USD 270 per installation. So even
if the throttling investment costs were lower than the price of a
single phase motor (approximately USD 200), the AC drive would
pay for itself before it has even worked a second.
Cost benefits of AC drives
40. 40 Guide to variable speed drives | Technical guide No. 4
Throttling AC drive
saving 50%
Power required 0.75 kW 0.37 kW
Annual energy 4000 hours/year 3000 kWh 1500 kWh
Annual energy cost with 0.1 300 USD 150 USD
USD/kWh
Maintenance/year 40 USD 5 USD
Total cost/year 340 USD 155 USD
Savings in one year: 185 USD!
Operational costs: maintenance and drive energy
In many surveys and experiments it has been proved that a 50%
energy saving is easily achieved with an AC drive. This means
that where power requirements with throttling would be 0.75
kW, with the AC drive it would be 0.37 kW. If a pump is used
4000 hours per year, throttling would need 3000 kWh and the
AC drive 1500 kWh of energy per year.
To calculate the savings, we need to multiply the energy con-
sumption by the energy price, which varies depending on the
country. Here USD 0.1 per kWh has been used.
As mentioned earlier, mechanical parts wear a lot and this is
why they need regular maintenance. It has been estimated
that whereas throttling requires USD 40 per year for service,
maintenance costs for an AC drive would be USD 5. In many
cases however, there is no maintenance required for a frequency
converter.
Therefore, the total savings in operating costs would be
USD 185, which is approximately half of the frequency converter’s
price for this power range. This means that the payback time of
the frequency converter is two years. So it is worth considering
that instead of yearly service for an old valve it might be more
profitable to change the whole system to an AC drive based
control. To retrofit an existing throttling system the pay-back
time is two years.
Cost benefits of AC drives
41. Technical guide No. 4 | Guide to variable speed drives 41
Total cost comparison
In the above figure, all the costs have been summarised. The
usual time for an operational cost calculation for this kind of
investment is 10 years. Here the operational costs are rated to
the present value with a 10% interest rate.
In the long run, the conventional method will be more than twice
as expensive as a frequency converter. Most of the savings with
the AC drive come from the operational costs, and especially
from the energy savings. It is in the installation that the highest
individual savings can be achieved, and these savings are real-
ised as soon as the drive is installed.
Taking the total cost figure into account, it is very difficult to
understand why only 3% of motors sold have a frequency con-
verter. In this guide we have tried to present the benefits of the
AC drive and why we at ABB think that it is absolutely the best
possible way to control your process.
Cost benefits of AC drives
42. 42 Guide to variable speed drives | Technical guide No. 4
Chapter 7 - Index
A
ABB 30, 33, 41
AC drive 24, 25, 26, 27, 28, 29,
30, 31, 34, 35, 36, 37, 38, 39, 40,
41
AC drives market 26
AC motor 13, 14
active power 16
B
belt drives 24
blowers 18
braking 17, 23
bypass control 22
C
coefficient of efficiency 16
Commissioning 39
commutator 24, 26
contactors 36
crane 17, 19
critical speed 30
crusher 18
current 14, 15, 16, 24
D
DC bus 14, 15
DC converter 24
DC drive 24, 26
DC motor 24, 26
Direct on-line starting 25
drive frequency 31
drive software 31
drive system 16, 20, 29, 33
E
electrical disturbances 33
electrical equipment room 24
electrical supply 16, 27, 33
electromagnetic compatibility 33
electromagnetic induction 14, 15
EMC 33
EMC directives 33
energy 14, 15, 22, 25, 26, 31, 37,
40, 41
F
fans 18
flux 14, 15
flying start 29, 32
flywheel 32
four quadrant drive 17
frequency converter 14, 16, 17,
20, 24, 28, 32, 33, 34, 40, 41
friction 18
fuses 36
H
harbour 19
hydraulic coupling 24
I
industrial processes 13
inertia 18, 32
input power 16
interference 15, 21
inverter 14, 15, 24
IP21 33
IP54 33
L
linear ramp 30
load capacity curves 28
M
machine 11, 13, 24, 29
magnetic flux 14, 15
maintenance 24, 25, 26, 37, 40
mechanical power 16
mechanical vibrations 29, 30
motor load 32
motor losses 16
motor phase 14
motor size 16
motor stall condition 31
motor windings 14, 15
N
nuisance faults 29
O
output power 16
P
power factor 16
power loss ride-through 29, 31
power plants 22, 37
process control 25, 26, 27, 29
processing system 10
pump 24, 25, 36, 40
R
rated speed 16
Reactive power 16
reactive power 16
reactors 36
rectifier 14
reference speed 30
reversing function 29
right hand rule 14
43. Technical guide No. 4 | Guide to variable speed drives 43
S
S-ramp 30
slip 14, 29, 32
squirrel cage motor 20, 24, 33
stall frequency 31
stall function 29, 31
stator 14
stepless control 15
T
temperature 15, 33
throttling 22, 36, 39, 40
torque 16, 17, 18, 19, 20, 28, 29,
30, 31, 32
transistors 16
V
valve 40
valves 24, 36
variable speed control 8, 21, 24
Variable Speed Drives 1, 3
voltage 14, 15, 16, 24, 27, 31
VSD 9, 15, 22, 23, 24, 25, 26
Index