Based on the popular constant volts per hertz principle, two improvement techniques are presented: keeping maximum torque constant or keeping magnetic flux constant. An open-loop inverter-three-phase squirrel-cage induction motor drive system that provides constant maximum torque or increased maximum torque and reduced slip speed at frequencies below the nominal frequency has been modeled, simulated and tested. Load performance analysis of the proposed system under different operation conditions was provided. These principles of operation are extended to the case of operation from variable frequency or variable voltage control method. Finally, the effects of the non-sinusoidal voltage and/or current wave shapes are covered. The results show that both suggested improvement techniques (constant torque or constant flux) improve the steady-state performance A.C. drive system with squirrel cage induction motors. The slip speed has been decreased and the starting torque and maximum torque have been increased, which means that the suggested control techniques can be used in drive systems with short time operating mode under light loads.
Vf control of three phase induction motor drive with different pwm techniquesAlexander Decker
This document discusses different pulse width modulation (PWM) techniques for controlling a three-phase induction motor, including sine triangle PWM (SPWM), third-harmonic PWM (THPWM), and space vector PWM (SVPWM). It simulates these techniques using MATLAB Simulink and compares their performance in terms of total harmonic distortion, output voltage harmonics, motor speed control, and efficiency. The results show that SVPWM provides superior performance with less harmonic distortion and higher utilization of the DC supply voltage. SVPWM also allows improved dynamic response when the induction motor is subjected to changes in reference speed or load torque. In conclusion, SVPWM is deemed the most efficient modulation technique for closed-loop control of induction motor drive systems
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.
A PROJECT REPORT SIM & SPEED CONTROL OF INDUCTIO DRIVEPawan Kumar
The document discusses speed control methods for three-phase induction motors. It analyzes the transients during starting of an induction motor with different machine parameters. It then examines various speed control methods including variable rotor resistance, variable stator voltage, and constant V/f control. Simulation results are presented to show the torque-speed characteristics for each method. Vector control is also introduced, which allows independent control of torque and flux.
This document proposes a direct torque control strategy for doubly fed induction machine-based wind turbines that can operate under voltage dips without crowbar protection. The control strategy generates a rotor flux amplitude reference to control the torque of the wind turbine and reduce stator and rotor overcurrents during faults. It also provides fast dynamic response. While the control does not eliminate the need for crowbar protection entirely, it can prevent the crowbar from activating during low-depth voltage dips. The direct torque control approach maintains machine connection to the grid and reduces torque oscillations during faults.
To Design and simulate 3-Ø Induction motor driveUmang Patel
This document is a project report submitted by four students to fulfill the requirements for a Bachelor of Engineering degree in Power Electronics. It outlines a project to design and simulate a three-phase induction motor drive using constant voltage-to-frequency control with a PIC microcontroller. The report includes sections on electric drives, induction motors, voltage source inverters, simulation in MATLAB and Proteus, PIC microcontrollers, hardware implementation, and PCB design. Tables and figures are included to illustrate the system components, simulation results, and PCB layouts.
The document summarizes research on using space vector modulation (SVM) for speed control of an induction motor driven by a three-phase inverter. It compares SVM to sine triangle pulse width modulation (SPWM) and finds that SVM provides better harmonic performance, higher DC bus utilization, and a more sinusoidal output voltage. The document simulates v/f control of an induction motor using SVM for both open-loop and closed-loop speed control systems. It is observed that the induction motor's performance is improved with SVM compared to SPWM modulation.
SPEED AND TORQUE CONTROL OF AN INDUCTION MOTOR WITH ANN BASED DTCijics
Due to advantages such as fast dynamic response, simple and robust control structure, direct torque
control (DTC) is commonly used method in high performance control method for induction motors. Despite
mentioned advantages, there are some chronically disadvantages with this method like high torque and
current ripples, variable switching behaviour and control problems at low speed rates. On the other hand,
artificial neural network (ANN) based control algorithms are getting increasingly popular in recent years
due to their positive contribution to the system performance. The purpose of this paper is investigating of
the effects of ANN integrated DTC method on induction motor performance by numerical simulations. For
this purpose, two different ANN models have been designed, trained and implemented for the same DTC
model. The first ANN model was designed to select optimum inverter and the second model was designed to
use in the determination of the flux vector position. Matlab/Simulink model of the proposed ANN based
DTC method was created in order to compare with the conventional DTC and the proposed DTC methods.
The simulation studies proved that the induction motor torque ripples have been reduced remarkably with
the proposed method and this approach can be a good alternative to the conventional DTC method for
induction motor control.
Matrix Converter based Direct Torque Control of Induction MotorNeehar NLN
This topic falls under the area of speed control of induction motor. The using of advanced power electronic converters provides better response. In this case, a AC/AC converter is used to control the induction motor.
Vf control of three phase induction motor drive with different pwm techniquesAlexander Decker
This document discusses different pulse width modulation (PWM) techniques for controlling a three-phase induction motor, including sine triangle PWM (SPWM), third-harmonic PWM (THPWM), and space vector PWM (SVPWM). It simulates these techniques using MATLAB Simulink and compares their performance in terms of total harmonic distortion, output voltage harmonics, motor speed control, and efficiency. The results show that SVPWM provides superior performance with less harmonic distortion and higher utilization of the DC supply voltage. SVPWM also allows improved dynamic response when the induction motor is subjected to changes in reference speed or load torque. In conclusion, SVPWM is deemed the most efficient modulation technique for closed-loop control of induction motor drive systems
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.
A PROJECT REPORT SIM & SPEED CONTROL OF INDUCTIO DRIVEPawan Kumar
The document discusses speed control methods for three-phase induction motors. It analyzes the transients during starting of an induction motor with different machine parameters. It then examines various speed control methods including variable rotor resistance, variable stator voltage, and constant V/f control. Simulation results are presented to show the torque-speed characteristics for each method. Vector control is also introduced, which allows independent control of torque and flux.
This document proposes a direct torque control strategy for doubly fed induction machine-based wind turbines that can operate under voltage dips without crowbar protection. The control strategy generates a rotor flux amplitude reference to control the torque of the wind turbine and reduce stator and rotor overcurrents during faults. It also provides fast dynamic response. While the control does not eliminate the need for crowbar protection entirely, it can prevent the crowbar from activating during low-depth voltage dips. The direct torque control approach maintains machine connection to the grid and reduces torque oscillations during faults.
To Design and simulate 3-Ø Induction motor driveUmang Patel
This document is a project report submitted by four students to fulfill the requirements for a Bachelor of Engineering degree in Power Electronics. It outlines a project to design and simulate a three-phase induction motor drive using constant voltage-to-frequency control with a PIC microcontroller. The report includes sections on electric drives, induction motors, voltage source inverters, simulation in MATLAB and Proteus, PIC microcontrollers, hardware implementation, and PCB design. Tables and figures are included to illustrate the system components, simulation results, and PCB layouts.
The document summarizes research on using space vector modulation (SVM) for speed control of an induction motor driven by a three-phase inverter. It compares SVM to sine triangle pulse width modulation (SPWM) and finds that SVM provides better harmonic performance, higher DC bus utilization, and a more sinusoidal output voltage. The document simulates v/f control of an induction motor using SVM for both open-loop and closed-loop speed control systems. It is observed that the induction motor's performance is improved with SVM compared to SPWM modulation.
SPEED AND TORQUE CONTROL OF AN INDUCTION MOTOR WITH ANN BASED DTCijics
Due to advantages such as fast dynamic response, simple and robust control structure, direct torque
control (DTC) is commonly used method in high performance control method for induction motors. Despite
mentioned advantages, there are some chronically disadvantages with this method like high torque and
current ripples, variable switching behaviour and control problems at low speed rates. On the other hand,
artificial neural network (ANN) based control algorithms are getting increasingly popular in recent years
due to their positive contribution to the system performance. The purpose of this paper is investigating of
the effects of ANN integrated DTC method on induction motor performance by numerical simulations. For
this purpose, two different ANN models have been designed, trained and implemented for the same DTC
model. The first ANN model was designed to select optimum inverter and the second model was designed to
use in the determination of the flux vector position. Matlab/Simulink model of the proposed ANN based
DTC method was created in order to compare with the conventional DTC and the proposed DTC methods.
The simulation studies proved that the induction motor torque ripples have been reduced remarkably with
the proposed method and this approach can be a good alternative to the conventional DTC method for
induction motor control.
Matrix Converter based Direct Torque Control of Induction MotorNeehar NLN
This topic falls under the area of speed control of induction motor. The using of advanced power electronic converters provides better response. In this case, a AC/AC converter is used to control the induction motor.
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.
Induction motors are AC motors that convert electrical energy to mechanical energy through electromagnetic induction. They are widely used in industry due to being rugged, reliable and economical. The speed of an induction motor is controlled either through the stator side by varying the supply frequency or voltage, or through the rotor side by adding external resistance or injecting slip frequency voltage. Modern variable speed drives allow induction motors to operate at variable speeds, providing benefits like energy savings and cost effectiveness.
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.
Induction motor modelling and applicationsUmesh Dadde
A three-phase induction motor is one of the most popular and versatile motor in electrical
power system and industries. It can perform the best when operated using a balanced three-phase
supply of the correct frequency. In spite of their robustness they do occasionally fail and their
resulting unplanned downtime can prove very costly. Therefore, condition monitoring of
electrical machines has received considerable attention in recent years.
DIRECT TORQUE CONTROL OF THREE PHASE INDUCTION MOTOR USING FOUR SWITCH THREE ...smadhumitha
This document discusses direct torque control of a three-phase induction motor using a four-switch inverter. It begins by reviewing existing literature on direct torque control methods and their limitations. The author then proposes using direct torque control with space vector modulation to control a four-switch inverter for improved dynamic response, reduced torque ripple, and lower harmonic distortion compared to existing methods. Simulation and hardware results demonstrate the benefits of the proposed method, such as lower torque ripple and current harmonic distortion.
1. direct torque control of induction motor with fuzzy controller a reviewMajdi Dadeq
This document reviews direct torque control of induction motors with fuzzy controllers. It begins by providing background on induction motors and their widespread use in industry. It then discusses direct torque control, which aims to directly control the stator flux and torque of induction motors through optimal selection of inverter switching vectors. The rest of the document discusses modeling induction motor drives using direct torque control with fuzzy logic applications and compares various techniques that have been proposed.
Speed Control System of Induction Motor by using Direct Torque Control Method...ijtsrd
Escalator is useful and act in the important part to carry passengers to the targeted floors of building. Every escalator must be driven by its own motor and this motor speed must be controled. To drive escalator with a constant speed, direct torque control technique is used to drive three phase squirrel cage induction motor. In this paper, the development of speed control system for three phase squirrel cage induction motor using a direct torque control method is presented and simulation for proposed system is done with the help of MATLAB SIMULINK. Soe Sandar Aung | Thet Naing Htun "Speed Control System of Induction Motor by using Direct Torque Control Method used in Escalator" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd27903.pdfPaper URL: https://www.ijtsrd.com/engineering/electrical-engineering/27903/speed-control-system-of-induction-motor-by-using-direct-torque-control-method-used-in-escalator/soe-sandar-aung
Updated field oriented control of induction motor.pptxMohit Sharma
It is a simulation work project done on a 5hp,440V/5A and 1440rpm Induction motor.It explains the control of induction motor using matlab-simulink algorithm by PI control as well as Fuzzy logic control.
Basic Presentation on Speed control of induction motorNileshBambhaniya2
This presentation prepared base on two research paper and electrical machine by NTPL IIT Madrash.
Basic presentation on speed control introduction and method of speed control.
Stator flux oriented vector control of wind driven self excited induction gen...Alexander Decker
This document discusses stator flux oriented vector control of a wind-driven self-excited induction generator connected to the grid through a cycloconverter. A MATLAB/Simulink model is developed to simulate the system. Key points:
1. A stator flux oriented control scheme is used to regulate the voltage and frequency of the self-excited induction generator.
2. A cycloconverter is used to interface the generator output to the grid, which helps eliminate harmonics but results in lower output voltage. This is compensated using a step-up transformer.
3. Simulation results under load and fault conditions like sudden load and short circuit are presented to demonstrate the effectiveness of the proposed control method in regulating
This document summarizes the modeling of a permanent magnet synchronous motor (PMSM) in Simulink. It describes how a PMSM is modeled in the rotor synchronous reference frame using Park equations. It discusses how the electromagnetic torque produced by the motor depends on the quadrature stator current. It also describes how the speed is controlled by controlling the electromagnetic torque through regulating the quadrature current. Finally, it presents the simulation results for the currents, torque, and speed of the modeled PMSM motor.
Speed Control of Induction Motor Drive Using Universal ControllerArif Shahriar
This paper presents the development of a universal controller board to control the speed of single or three phase induction motors. The controller uses a microcontroller and pulse width modulation inverter to generate variable frequency supply to the motor. MATLAB Simulink was used to simulate a three phase inverter circuit controlling an induction motor. Hardware was also implemented including power, control, and driver circuits. Testing showed the fan load speed could be varied by changing the modulation index with the selector switch, demonstrating variable speed control of the induction motor. The designed system provides a low-cost and versatile solution for motor speed control applications.
Speed control of single phase induction motor with variable frequency voltage...SHAHRUKH ALAM
This document discusses speed control of a single phase induction motor using a variable frequency voltage source inverter (VSI). It begins with an objective to generate a variable frequency output from the inverter to run the motor at variable speeds proportional to the frequencies. It then discusses single phase induction motor speed control, the components of a variable frequency drive including rectifier and inverter stages, and how a VSI can provide speed control. It also touches on modulation techniques like PWM that are used to control the VSI output voltage. MATLAB simulations demonstrate speed control at different frequencies. Advantages include energy savings and reduced wear. Applications include pumps, fans, and conveyors.
Speed control of Three phase Induction motor using AC voltage regulatorShivagee Raj
The role of AC Voltage Regulator in speed control of three phase Induction Motor is to vary the supply voltage which in turn, changes the speed of motor .
SPEED CONTROL OF INDUCTION MACHINE WITH REDUCTION IN TORQUE RIPPLE USING ROBU...IAEME Publication
In this paper a novel and simple algorithm for three-phase induction motor(IM) under Direct Torque Control (DTC) scheme using Classic DTC switching table for dynamic torque ripple reduction and space-vector modulation scheme for steady state torque and flux control is proposed. The proposed scheme having the advantages of low torque ripples as well as constant switching frequency.
Simulation results are given to prove the ability of the proposed method obtaining good speed control bandwidth while overcoming classic DTC and DTC-SVM drawbacks.
Review of Improved Direct Torque Control Methodologies for Induction Motor Dr...AM Publications
ecoupled control of induction motor drives is possible using Direct Torque Control (DTC) method which
is very simple control strategy compared to field oriented control. In this method direct torque control is achieved by
selecting suitable inverter switching voltage vector from a lookup table. But drawback of this method is that it
produces toque ripples. Also the switching frequency of inverter switches is not constant. Many methods have been
proposed to address these issues of DTC. This paper reviews various methodologies which are suggested to improve
performance of basic DTC induction motor drive.
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.
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.
This document provides an overview of vector control of AC induction motors compared to scalar control. Vector control decouples the torque and flux produced by the motor, allowing for more precise independent control. It does this by controlling the direct current (Id) that produces flux and quadrature current (Iq) that produces torque. There are two approaches to vector control - direct field oriented control that directly measures the rotor angle and indirect field oriented control that indirectly measures it using slip speed. Key benefits of vector control are fast transient response since torque can be controlled without affecting flux, and ability to control speed in all four quadrants.
Speed Control of The Three Phase Induction Motor via changing the line voltageYazan Yousef
This report introduces a method of speed control of the three-phase induction motor driving a fan using the MATLAB. A MATLAB code and Simulink are used to propose the system and to study the speed control method. The method is to control the speed by changing the line voltage. Moreover, the motor performance especially the torque and power are studied during varying the voltage.
Study of Vector Control Algorithm and Inverter design for BLDC Motor, V/f con...Amol Mahurkar
This document summarizes a study on vector control algorithms and inverter design for BLDC motors. It discusses the objectives of studying BLDC motor operation, different control algorithms including vector control, and inverter design. It also covers V/F control of induction motors. Key topics covered include Clarke/Park transformations, sensorless control, inverter topologies, and a comparison of vector and V/F control techniques. The document is authored by engineering students and provides an overview of various motor control concepts and algorithms.
speed control of three phase induction motorAshvani Shukla
This document summarizes various methods for controlling the speed of three-phase induction motors. It discusses that induction motors are commonly used in industry due to their low cost and rugged construction but operate at constant speed. Various speed control methods are then outlined, including stator voltage control, stator frequency control, and stator current control. V/F control is also explained in detail along with its advantages for providing efficient motor speed control. The document concludes by discussing applications in industry and topics for further research.
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.
Induction motors are AC motors that convert electrical energy to mechanical energy through electromagnetic induction. They are widely used in industry due to being rugged, reliable and economical. The speed of an induction motor is controlled either through the stator side by varying the supply frequency or voltage, or through the rotor side by adding external resistance or injecting slip frequency voltage. Modern variable speed drives allow induction motors to operate at variable speeds, providing benefits like energy savings and cost effectiveness.
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.
Induction motor modelling and applicationsUmesh Dadde
A three-phase induction motor is one of the most popular and versatile motor in electrical
power system and industries. It can perform the best when operated using a balanced three-phase
supply of the correct frequency. In spite of their robustness they do occasionally fail and their
resulting unplanned downtime can prove very costly. Therefore, condition monitoring of
electrical machines has received considerable attention in recent years.
DIRECT TORQUE CONTROL OF THREE PHASE INDUCTION MOTOR USING FOUR SWITCH THREE ...smadhumitha
This document discusses direct torque control of a three-phase induction motor using a four-switch inverter. It begins by reviewing existing literature on direct torque control methods and their limitations. The author then proposes using direct torque control with space vector modulation to control a four-switch inverter for improved dynamic response, reduced torque ripple, and lower harmonic distortion compared to existing methods. Simulation and hardware results demonstrate the benefits of the proposed method, such as lower torque ripple and current harmonic distortion.
1. direct torque control of induction motor with fuzzy controller a reviewMajdi Dadeq
This document reviews direct torque control of induction motors with fuzzy controllers. It begins by providing background on induction motors and their widespread use in industry. It then discusses direct torque control, which aims to directly control the stator flux and torque of induction motors through optimal selection of inverter switching vectors. The rest of the document discusses modeling induction motor drives using direct torque control with fuzzy logic applications and compares various techniques that have been proposed.
Speed Control System of Induction Motor by using Direct Torque Control Method...ijtsrd
Escalator is useful and act in the important part to carry passengers to the targeted floors of building. Every escalator must be driven by its own motor and this motor speed must be controled. To drive escalator with a constant speed, direct torque control technique is used to drive three phase squirrel cage induction motor. In this paper, the development of speed control system for three phase squirrel cage induction motor using a direct torque control method is presented and simulation for proposed system is done with the help of MATLAB SIMULINK. Soe Sandar Aung | Thet Naing Htun "Speed Control System of Induction Motor by using Direct Torque Control Method used in Escalator" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd27903.pdfPaper URL: https://www.ijtsrd.com/engineering/electrical-engineering/27903/speed-control-system-of-induction-motor-by-using-direct-torque-control-method-used-in-escalator/soe-sandar-aung
Updated field oriented control of induction motor.pptxMohit Sharma
It is a simulation work project done on a 5hp,440V/5A and 1440rpm Induction motor.It explains the control of induction motor using matlab-simulink algorithm by PI control as well as Fuzzy logic control.
Basic Presentation on Speed control of induction motorNileshBambhaniya2
This presentation prepared base on two research paper and electrical machine by NTPL IIT Madrash.
Basic presentation on speed control introduction and method of speed control.
Stator flux oriented vector control of wind driven self excited induction gen...Alexander Decker
This document discusses stator flux oriented vector control of a wind-driven self-excited induction generator connected to the grid through a cycloconverter. A MATLAB/Simulink model is developed to simulate the system. Key points:
1. A stator flux oriented control scheme is used to regulate the voltage and frequency of the self-excited induction generator.
2. A cycloconverter is used to interface the generator output to the grid, which helps eliminate harmonics but results in lower output voltage. This is compensated using a step-up transformer.
3. Simulation results under load and fault conditions like sudden load and short circuit are presented to demonstrate the effectiveness of the proposed control method in regulating
This document summarizes the modeling of a permanent magnet synchronous motor (PMSM) in Simulink. It describes how a PMSM is modeled in the rotor synchronous reference frame using Park equations. It discusses how the electromagnetic torque produced by the motor depends on the quadrature stator current. It also describes how the speed is controlled by controlling the electromagnetic torque through regulating the quadrature current. Finally, it presents the simulation results for the currents, torque, and speed of the modeled PMSM motor.
Speed Control of Induction Motor Drive Using Universal ControllerArif Shahriar
This paper presents the development of a universal controller board to control the speed of single or three phase induction motors. The controller uses a microcontroller and pulse width modulation inverter to generate variable frequency supply to the motor. MATLAB Simulink was used to simulate a three phase inverter circuit controlling an induction motor. Hardware was also implemented including power, control, and driver circuits. Testing showed the fan load speed could be varied by changing the modulation index with the selector switch, demonstrating variable speed control of the induction motor. The designed system provides a low-cost and versatile solution for motor speed control applications.
Speed control of single phase induction motor with variable frequency voltage...SHAHRUKH ALAM
This document discusses speed control of a single phase induction motor using a variable frequency voltage source inverter (VSI). It begins with an objective to generate a variable frequency output from the inverter to run the motor at variable speeds proportional to the frequencies. It then discusses single phase induction motor speed control, the components of a variable frequency drive including rectifier and inverter stages, and how a VSI can provide speed control. It also touches on modulation techniques like PWM that are used to control the VSI output voltage. MATLAB simulations demonstrate speed control at different frequencies. Advantages include energy savings and reduced wear. Applications include pumps, fans, and conveyors.
Speed control of Three phase Induction motor using AC voltage regulatorShivagee Raj
The role of AC Voltage Regulator in speed control of three phase Induction Motor is to vary the supply voltage which in turn, changes the speed of motor .
SPEED CONTROL OF INDUCTION MACHINE WITH REDUCTION IN TORQUE RIPPLE USING ROBU...IAEME Publication
In this paper a novel and simple algorithm for three-phase induction motor(IM) under Direct Torque Control (DTC) scheme using Classic DTC switching table for dynamic torque ripple reduction and space-vector modulation scheme for steady state torque and flux control is proposed. The proposed scheme having the advantages of low torque ripples as well as constant switching frequency.
Simulation results are given to prove the ability of the proposed method obtaining good speed control bandwidth while overcoming classic DTC and DTC-SVM drawbacks.
Review of Improved Direct Torque Control Methodologies for Induction Motor Dr...AM Publications
ecoupled control of induction motor drives is possible using Direct Torque Control (DTC) method which
is very simple control strategy compared to field oriented control. In this method direct torque control is achieved by
selecting suitable inverter switching voltage vector from a lookup table. But drawback of this method is that it
produces toque ripples. Also the switching frequency of inverter switches is not constant. Many methods have been
proposed to address these issues of DTC. This paper reviews various methodologies which are suggested to improve
performance of basic DTC induction motor drive.
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.
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.
This document provides an overview of vector control of AC induction motors compared to scalar control. Vector control decouples the torque and flux produced by the motor, allowing for more precise independent control. It does this by controlling the direct current (Id) that produces flux and quadrature current (Iq) that produces torque. There are two approaches to vector control - direct field oriented control that directly measures the rotor angle and indirect field oriented control that indirectly measures it using slip speed. Key benefits of vector control are fast transient response since torque can be controlled without affecting flux, and ability to control speed in all four quadrants.
Speed Control of The Three Phase Induction Motor via changing the line voltageYazan Yousef
This report introduces a method of speed control of the three-phase induction motor driving a fan using the MATLAB. A MATLAB code and Simulink are used to propose the system and to study the speed control method. The method is to control the speed by changing the line voltage. Moreover, the motor performance especially the torque and power are studied during varying the voltage.
Study of Vector Control Algorithm and Inverter design for BLDC Motor, V/f con...Amol Mahurkar
This document summarizes a study on vector control algorithms and inverter design for BLDC motors. It discusses the objectives of studying BLDC motor operation, different control algorithms including vector control, and inverter design. It also covers V/F control of induction motors. Key topics covered include Clarke/Park transformations, sensorless control, inverter topologies, and a comparison of vector and V/F control techniques. The document is authored by engineering students and provides an overview of various motor control concepts and algorithms.
speed control of three phase induction motorAshvani Shukla
This document summarizes various methods for controlling the speed of three-phase induction motors. It discusses that induction motors are commonly used in industry due to their low cost and rugged construction but operate at constant speed. Various speed control methods are then outlined, including stator voltage control, stator frequency control, and stator current control. V/F control is also explained in detail along with its advantages for providing efficient motor speed control. The document concludes by discussing applications in industry and topics for further research.
The document discusses variable frequency drives (VFDs) and their applications. VFDs can control the frequency and voltage applied to AC motors to vary their speed. They allow control of parameters like voltage, frequency, and maximum temperature. Common applications of VFDs include heating, ventilation, air conditioning, wastewater treatment, fans, blowers, textile mills and rolling mills. VFDs provide variable frequency and voltage using voltage source inverters, cycloconverters or choppers to reduce harmonic injection into the AC supply.
Two leg three-phase inverters (FSTPIs) have been proposed to be used in low-power; low-cost applications because of the reduced number of semiconductor devices, and space vector pulse width modulation (SVPWM) techniques have also been introduced to control FSTPIs. However, high-performance controllers are needed to implement complicated SVPWM algorithms, which limit their low-cost applications. To simplify algorithms and reduce the cost of implementation, an equivalent scalar method for SVPWM of FSTPIs is proposed. SVPWM for FSTPIs is actually a sine PWM by modulating two sine waves of 600 phase difference with a triangle wave, but in this method third harmonics doesn’t eliminated. So as to eliminate the third harmonics we have to compose a high frequency sine wave to on existing sine waves. So such a special sine PWM can be used to control FSTPIs. The Mathematical and simulation results demonstrate the validity of the proposed method.
http://www.mathworks.com/matlabcentral/fileexchange/authors/126814
Multilevel inverter fed induction motor driveseSAT Journals
Abstract Induction motor drive is used in almost all industries including oil and gas sectors, production plants and process industries. Speed control of induction motor is a major concern. The proposed technology implements a better speed control for induction motor drives using a multilevel inverter. The switching sequences are generated by optimized pre-calculated angles for controlling induction motor. And also with the use of a multi-level inverter there is lower distortion of output voltages and Total Harmonic Distortion (THD) of machine currents under steady state operating conditions can be minimized. THD can be further reduced by optimizing the switching angles. This technology can be extended to higher levels of output voltages by using an n state multilevel inverter. In this paper, a seven level multilevel inverter is proposed, its simulation is done in MATLAB/Simulink and the results were verified by experimenting on a hardware prototype. This could be extended to higher levels of voltage waveform and can be used in photovoltaics. A multilevel inverter could be a better choice as a dc-dc converter in solar power circuits. Keywords: Multilevel inverter, optimal pulse with modulation, total harmonic d1istortion.
This project aims to implement sensorless speed detection of induction motors using fluctuations in the zero crossings of the three-phase motor current. Current transformers are used to sense the motor current, and a microcontroller analyzes the zero crossing times to determine motor speed without the need for sensors. The current signals are buffered using voltage followers before being input to the microcontroller. Fast Fourier transform algorithms are then used to detect the motor speed based on fluctuations in the current zero crossings. This sensorless method provides a low-cost solution for speed measurement in applications where sensors cannot be used.
Speed Control Techniques for Induction Motor - A Reviewijsrd.com
In this paper, various types of speed control methods for the single phase induction motor are described. Speed can be controlled to control the frequency or slip can be controlled to control the torque. Then flux and torque are also function of frequency and voltage. Various methods are used to control the flux and voltage. This paper is focused on sliding mode control technique for induction motor.
Solid-state drives (SSDs) are storage devices that use solid-state flash memory instead of rotating disks. SSDs have no moving parts, faster access times than hard disk drives, lower power consumption, and can withstand physical shock better than hard drives. However, SSDs are currently more expensive than hard drives and offer less storage capacity. SSDs are commonly found in servers, desktop and laptop computers, camcorders, gaming consoles, smartphones, and other portable electronic devices.
Design of drive for speed control of induction pptAvinash Varanasi
This document presents a project to control the speed of an induction motor using a variable frequency/variable voltage (V/F) method. The project team includes 6 members and is guided by Arun Kumar. The system uses a microcontroller to provide easy control over and adjustable speed capability for the induction motor. It consists of electronic components, a microcontroller, and an LCD display. The motor speed can be selected and adjusted to user-defined speeds under various load conditions, with the V/F ratio maintained constant to keep the air gap flux stable. Experimental results showing motor speed at different voltages, frequencies and loads are presented in a table.
The document discusses various propagation mechanisms that affect radio signals, including reflection, diffraction, scattering, and their effects on signal strength over distance. It also covers propagation models like free space path loss, two-ray ground reflection model, and log-distance path loss for estimating average received signal power at a given distance. Fresnel zones and knife-edge diffraction are explained as factors in signal propagation around obstructions. Log-normal shadowing is described as a statistical model to account for variations from the average path loss.
SSD - Solid State Drive PPT by Shyam jos Shyam Jos
Solid State Drive (SSD)
In 1995, M-Systems introduced the first flash-based solid-state drives. SSDs use non-volatile solid state memory like NAND flash or DRAM to store data without moving parts, distinguishing them from traditional hard disk drives. SSDs have significant performance advantages over HDDs with faster access times and read/write speeds, higher reliability since there are no moving parts, lower power consumption, and silent operation. However, SSDs currently have higher costs and offer less storage capacity than HDDs.
Introduction To Wireless Fading ChannelsNitin Jain
The document summarizes key concepts related to wireless fading channels, including:
1. Multipath fading causes fluctuations in signal strength over small physical distances due to constructive and destructive interference from multiple signal paths.
2. Rayleigh fading occurs when there is no line-of-sight path between transmitter and receiver, resulting in fast, large fluctuations in signal strength over small physical distances.
3. Doppler spread and coherence time describe how quickly the wireless channel varies over time due to mobility, with fast fading occurring if the channel changes significantly within a symbol period.
The document discusses different types of AC motors including induction motors and synchronous motors. It provides details on their construction, working principles, starting methods, torque characteristics and applications. Some key points covered are:
- Induction motors are the most commonly used AC motors due to their simple and rugged construction. They operate at a slightly lower speed than synchronous speed.
- Synchronous motors rotate exactly at the synchronous speed of the rotating magnetic field. They cannot be started directly and require an external prime mover to start.
- Both induction and synchronous motors require maintenance like cleaning electrical connections and checking for overheating to ensure safe and efficient operation.
Advanced Three Phase PWM Inverter Control Using MicrocontrollerIOSR Journals
This document describes an advanced three-phase PWM inverter topology called a Z-Source inverter and its control using a microcontroller. A microcontroller generates PWM signals to control the inverter using a modified maximum constant boost PWM method. Hardware is designed including a control circuit, driver circuit, Z-Source network, main inverter bridge and power supplies. Experimental results are presented demonstrating generation of three-phase PWM signals to drive an induction motor load.
This document outlines and describes the key components and operating principles of three-phase induction motors, which are widely used in industrial applications due to their continuous operation. It discusses the main types of electrical machines and induction motors, including squirrel cage and slip ring induction motors. The document explains the basic working principle of three-phase induction motors, involving the generation of a rotating magnetic field in the stator that induces current in the rotor. It also describes the main components of three-phase induction motors such as the frame, stator, rotor, and windings.
Powerpoint Search Engine has collection of slides related to specific topics. Write the required keyword in the search box and it fetches you the related results.
Study On Speed Control of DC MOTOR Using ThyristorIRJET Journal
This document discusses speed control of a DC motor using a thyristor. It first provides background on DC motors and thyristors. It then presents the mathematical model of a separately excited DC motor. Various methods for controlling DC motor speed are described, including armature voltage control, armature resistance control, and flux control. Single phase half wave, full wave, and dual converter drives are introduced as techniques for implementing thyristor-based speed control. A simulation model is presented to observe the effect of varying the firing angle of a single phase full converter on the torque-speed characteristic of the DC motor. The document concludes that thyristor-based drives can effectively control DC motor speed.
Implementation of ac induction motor control using constant vhz principle and...eSAT Journals
Abstract
This paper presents the hardware implementation of V/f control of induction motor using sine wave PWM method. Because of its
simplicity, the V/F control also called as the scalar control, is the most widely used speed control method in the industrial
applications. In this method the ratio between stator voltage to frequency is maintained constant so that the stator flux is
maintained constant. As the stator flux is maintained constant, the torque developed by the motor depends only on the slip speed
and is independent of the supply frequency. Thus we can control the speed and torque of induction motor by simply controlling the
slip speed of induction motor. The complete control is achieved with the help of TMS320F28027 Development Board. One of the
basic requirements of this scheme is the PWM inverter. The gating signals are generated using sine wave PWM technique.
Implementation issues such as PWM signal generation, ramp control, v/f control, inverter design are discussed. The results are
discussed based on the various waveforms.
KeyWords: v/f control, Induction motor, PWM, and Scalar control
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Analysis of SVPWM for Inverter fed DTC of Induction motor DriveIJSRED
This document analyzes and compares space vector pulse width modulation (SVPWM) and sinusoidal pulse width modulation (SPWM) for controlling an induction motor drive using direct torque control (DTC). It finds that SVPWM reduces harmonic content in voltages and currents compared to SPWM, allowing for higher output voltage. The document simulates an induction motor drive using SVPWM and proportional-integral control in MATLAB/Simulink. The results show SVPWM provides improved torque waveform quality over SPWM and DTC with a PI controller alone.
Performance Analysis Of Induction Motor For Voltage Mode And Current Mode Con...IRJET Journal
This document discusses the performance analysis of an induction motor using voltage mode and current mode control. It compares hysteresis current control and space vector pulse width modulation (SVPWM). Hysteresis control directly limits current peaks but SVPWM provides higher voltage output and lower harmonic distortion. The document simulates an induction motor drive using SVPWM-based hysteresis current control in MATLAB. Key steps include Clark transformation to generate reference signals, switching between active and zero vectors to synthesize the reference signal, and using hysteresis control to generate PWM signals from current errors. Simulation results show the SVPWM controller provides good speed and current regulation for the induction motor.
Design of Electric Drive for Vehicular Application Using Vector ControlIOSR Journals
This document describes the design of an electric drive system for a vehicular application using vector control. It proposes an induction motor fed by a three-phase voltage source inverter whose input comes from a boost converter. Indirect vector control is chosen as the control scheme due to its ability to provide fast and accurate torque control without needing rotor position sensors. Simulation results show the motor is able to achieve speed control within 2.5 seconds with less than 4% deviation from the reference speed.
DC-link voltage balancing and control of qZ-source inverter fed induction mo...IJECEIAES
Poor performance of the motor drive system is caused when the direct currentlink (DC-link) capacitor voltages of the inverter are not sufficiently generated. This is mainly because of the various load torque changes and input voltage fluctuation. The qZ-source inverter operates with a fully shoot-through technique. This technique causes mismatching between the upper and lower DC-link capacitor voltages. Without capacitor voltage-balancing function, the desired DC-link capacitor voltages could not be provided or maintained when there are load and speed changes. A Sawtooth carrier-based simple boost triple-sixty-degree (TSD) pulse width modulation (PWM) technique is used to drive the qZ-source T-type inverter because this technique can give a more significant boost DC-link voltage than a traditional simple boost PWM technique. Proportional integral (PI) controller is applied for the DC-link voltage controller to achieve the fast response and less steady-state error. The simulation model was constructed for a 4 kW, 400 V, 1,400 rpm induction motor (IM) drive system used in rolling mill using MATLAB/Simulink with and without voltage balancing function. As a result, DC-link voltages of the qZ-source T-type inverter fed the induction motor drive system could be controlled using a capacitor voltage-balancing function and the output power of the motor from the simulation result is approximately equal to 4 kW
Dual inverter fed induction motor drives provide more advantages in contrast with other multilevel inverter drives. Coupled PWM techniques provide good standard of output voltage than the decoupled PWM techniques for dual inverter configuration. In this paper analysis of open end winding induction motor by coupled random PWM signals and decoupled SVPWM signals was carried out. Induction motor by random PWM technique generate low acoustic noise and electromagnetic interference to near by systems. The performance evaluation of the drive wss implemented in MATLAB/simulink and the results were presented.
An induction motor (IM) has been the workhorse of the industry for decades. It is due to its robustness, simple construction, requiring less maintenance and cheap. One of the most widely adopted IM drive control schemes for industrial applications is the open-loop constant V/Hz. In this paper, the important elements of an open-loop constant V/Hz drives are presented. These include the fundamental concept of a constant V/Hz scheme, the voltage source inverter (VSI) and its modulation schemes. Techniques that are commonly used to solve problems of low-speed operation and rotor speed regulation are briefly described. Simulations using MATLAB/Simulink package are used to help in illustrating these fundamental concepts. Finally, simple laboratory-scale experiments are conducted to implement the constant V/Hz control scheme on a ¼ hp induction motor. The constant V/Hz control is implemented using the DS1104 controller board with the C codes automatically generated from the Simulink model. A closer look at the current waveform when fref=25 Hz and 12 Hz and its respective Fourier analysis are presented. The results show that the high-frequency harmonic contents around the switching frequency can be observed for both cases, and the voltage waveform presents more spike noises in constrast to current waveform.
Induction motor harmonic reduction using space vector modulation algorithmjournalBEEI
The vector control was proposed as an alternative to the scalar control for AC machines control. Vector control provide high operation performance in steady state and transient operation. However, the variable switching frequency of vector control causes high flux and torque ripples which lead to an acoustical noise and degrade the performance of the control scheme. The insertion of the space vector modulation was a very useful solution to reduce the high ripples level inspite of its complexity. Numerical simulation results obtained in MATLAB/Simulink show the good dynamic performance of the proposed vector control technique and the effectiveness of the proposed sensorless strategy in the presence of the sudden load torque basing on the integral backstepping approach capabilities on instant perturbation rejection.
Keywords
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
This document discusses the calculation of total current harmonic distortion for permanent magnet synchronous motors (PMSM) using pulse width modulation (PWM) methods. It involves modeling and simulating a PMSM drive system in MATLAB/Simulink to analyze the effects on current harmonics. Field oriented control is used to control the rotor current and regulate speed. Simulation results show that PWM control produces lower total harmonic distortion compared to hysteresis control. Vector control methods produce even lower harmonics compared to PWM inverters alone. The document analyzes the harmonic spectra from the simulations to evaluate the performance of different control schemes.
Control of variable reluctance machine (8/6) by artificiel intelligence techn...IJECEIAES
The non-linearity of variable-Reluctance Machine (8/6) and the dependence of machine inductance on rotor position and applied current complicate the development of the control strategies of drives using variable-Reluctance Machine variable-Reluctance Machine (VRM). The classical-control algorithms for example of derived full proportional action may prove sufficient if the requirements on the accuracy and performance of systems are not too strict. In the opposite case and particularly when the controlled part is submitted to strong nonlinearity and to temporal variations, control techniques must be designed which ensure the robustness of the process with respect to the uncertainties on the parameters and their variations. These techniques include artificial-intelligence-based techniques constituted of neural networks and fuzzy logic. This technique has the ability to replace PID regulators by nonlinear ones using the human brain’s reasoning and functioning and is simulated by using MATLAB/Simulink software. Finally, by using obtained waveforms, these results will be compared.
Analysis and Simulation of Asynchronous Machine Connected with Load Accomplis...YogeshIJTSRD
This paper presents the simulation analysis of pulse width modulation based induction motor drive. The main objective of this paper is analysis of asynchronous machine with PWM fed inverter and harmonic analysis of active and reactive power as well as voltage and current. Space vector pulse width modulation technique is used in various industrial applications. Variation in voltage and frequency supply to ac drives is produced from a voltage source inverter and space vector PWM is used frequently now a day due to their easy understanding. This work is based on a SVPWM based induction motor based on space vector theory. The simulation is done on MATLAB software and the simulation results obtained and analyzed. Ms. Neetu Khunte | Mr. Abhijeet Lal | Mr. Abhishek Agrawal "Analysis and Simulation of Asynchronous Machine Connected with Load Accomplished with Chopper Control and PWM Based Inverter" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-4 , June 2021, URL: https://www.ijtsrd.compapers/ijtsrd41190.pdf Paper URL: https://www.ijtsrd.comengineering/electronics-and-communication-engineering/41190/analysis-and-simulation-of-asynchronous-machine-connected-with-load-accomplished-with-chopper-control-and-pwm-based-inverter/ms-neetu-khunte
This document summarizes a research paper that studies fault tolerance and power quality in a DFIG (Doubly Fed Induction Generator) wind turbine system using a UPFC (Unified Power Flow Controller). It first provides background on issues with integrating large-scale wind power into electric grids. It then describes using a UPFC and relay protection system to mitigate power quality issues in a grid-connected DFIG wind energy system, which is simulated in MATLAB. The document outlines the theory of power flow in a DFIG and issues related to power quality during grid disturbances like voltage dips from faults.
In this paper, a new approach is proposed for keeping the RMS voltage output constant, the system is supplying by a self-excited induction generator (SEIG) driven by a controlled DC motor with variable speed and load. The scheme used in this paper is based on a classical Proportional-Integral regulator wich controls a SPWM switching. A MATLAB Simulink model of the system is developed to maintain the AC voltage at the desired value. Then a comparison is examined between simulation and experimental results using dSPACE board. The results are provided to verify the effectiveness of this approach and it gives very high performance.
This document presents a comparative study of five-level and seven-level diode-clamped inverters controlled by space vector pulse width modulation (SVPWM). MATLAB/SIMULINK models of the two inverter topologies were developed. SVPWM control algorithms based on symmetrical sequence were used for each inverter. Both inverters were simulated driving an induction motor. The results showed that the seven-level inverter produced less harmonic distortion and torque fluctuations in the motor, while the five-level inverter had lower commutation losses. The seven-level inverter provided better motor dynamic response.
Performance Improvement of Multi Level Inverter fed Vector Controlled Inducti...IJPEDS-IAES
In this paper, the analysis of space vector based multi level inverter (MLI) fed vector controlled induction motor drive for a low speed operation is presented. The performance of indirect field oriented controlled induction motor drive (IMD) is poor with two-level inverter for low speed operations (LSO). The reduction in performance and peak value of torque are mainly due to the non-linearity caused by stator voltage drop and inverter. Hence the performance factors of induction motor drive are analyzed with the multi level inverters under different operating conditions. In this approach, the steady state ripple content in the current and torque waveforms are reduced and that to ripple content of torque is reduced from 0.15 to 0.05 under steady state with five-level inverter. When there is a step change in the load torque, the momentary decrease in speed with five-level inverter is less when compared two and three-level inverters and the speed response reaches the reference value very quickly with five-level inverter during steady state and transient periods. So the overall performance of drive is improved with five- level inverter when compared to two-level and three- level inverters under low speed operations.
A comparative analysis of speed control of separately excited dc motors by co...IAEME Publication
This document compares speed control of a separately excited DC motor using conventional and artificial intelligence (AI) based controllers. It first provides background on separately excited DC motors and discusses their conventional control using a proportional-integral (PI) controller. It then introduces fuzzy logic and adaptive neuro-fuzzy inference system (ANFIS) controllers for speed control. The controllers are modeled and tested in MATLAB/Simulink. Simulation results show AI controllers provide better performance and robustness during large load disturbances compared to the conventional PI controller.
Similar to V/F Control of Squirrel Cage Induction Motor Drives Without Flux or Torque Measurement Dependency (20)
The Use of Java Swing’s Components to Develop a WidgetWaqas Tariq
Widget is a kind of application provides a single service such as a map, news feed, simple clock, battery-life indicators, etc. This kind of interactive software object has been developed to facilitate user interface (UI) design. A user interface (UI) function may be implemented using different widgets with the same function. In this article, we present the widget as a platform that is generally used in various applications, such as in desktop, web browser, and mobile phone. We also describe a visual menu of Java Swing’s components that will be used to establish widget. It will assume that we have successfully compiled and run a program that uses Swing components.
3D Human Hand Posture Reconstruction Using a Single 2D ImageWaqas Tariq
Passive sensing of the 3D geometric posture of the human hand has been studied extensively over the past decade. However, these research efforts have been hampered by the computational complexity caused by inverse kinematics and 3D reconstruction. In this paper, our objective focuses on 3D hand posture estimation based on a single 2D image with aim of robotic applications. We introduce the human hand model with 27 degrees of freedom (DOFs) and analyze some of its constraints to reduce the DOFs without any significant degradation of performance. A novel algorithm to estimate the 3D hand posture from eight 2D projected feature points is proposed. Experimental results using real images confirm that our algorithm gives good estimates of the 3D hand pose. Keywords: 3D hand posture estimation; Model-based approach; Gesture recognition; human- computer interface; machine vision.
Camera as Mouse and Keyboard for Handicap Person with Troubleshooting Ability...Waqas Tariq
Camera mouse has been widely used for handicap person to interact with computer. The utmost important of the use of camera mouse is must be able to replace all roles of typical mouse and keyboard. It must be able to provide all mouse click events and keyboard functions (include all shortcut keys) when it is used by handicap person. Also, the use of camera mouse must allow users troubleshooting by themselves. Moreover, it must be able to eliminate neck fatigue effect when it is used during long period. In this paper, we propose camera mouse system with timer as left click event and blinking as right click event. Also, we modify original screen keyboard layout by add two additional buttons (button “drag/ drop” is used to do drag and drop of mouse events and another button is used to call task manager (for troubleshooting)) and change behavior of CTRL, ALT, SHIFT, and CAPS LOCK keys in order to provide shortcut keys of keyboard. Also, we develop recovery method which allows users go from camera and then come back again in order to eliminate neck fatigue effect. The experiments which involve several users have been done in our laboratory. The results show that the use of our camera mouse able to allow users do typing, left and right click events, drag and drop events, and troubleshooting without hand. By implement this system, handicap person can use computer more comfortable and reduce the dryness of eyes.
A Proposed Web Accessibility Framework for the Arab DisabledWaqas Tariq
The Web is providing unprecedented access to information and interaction for people with disabilities. This paper presents a Web accessibility framework which offers the ease of the Web accessing for the disabled Arab users and facilitates their lifelong learning as well. The proposed framework system provides the disabled Arab user with an easy means of access using their mother language so they don’t have to overcome the barrier of learning the target-spoken language. This framework is based on analyzing the web page meta-language, extracting its content and reformulating it in a suitable format for the disabled users. The basic objective of this framework is supporting the equal rights of the Arab disabled people for their access to the education and training with non disabled people. Key Words : Arabic Moon code, Arabic Sign Language, Deaf, Deaf-blind, E-learning Interactivity, Moon code, Web accessibility , Web framework , Web System, WWW.
Real Time Blinking Detection Based on Gabor FilterWaqas Tariq
The document proposes a new method for real-time blinking detection based on Gabor filters. It begins by reviewing existing methods and their limitations in dealing with noise, variations in eye shape, and blinking speed. The proposed method uses a Gabor filter to extract the top and bottom arcs of the eye from an image. It then measures the distance between these arcs and compares it to a threshold: a distance below the threshold indicates a closed eye, while a distance above indicates an open eye. The document claims this Gabor filter-based approach is robust to noise, variations in eye shape and blinking speed. It presents experimental results showing the method can accurately detect blinking across different users.
Computer Input with Human Eyes-Only Using Two Purkinje Images Which Works in ...Waqas Tariq
A method for computer input with human eyes-only using two Purkinje images which works in a real time basis without calibration is proposed. Experimental results shows that cornea curvature can be estimated by using two light sources derived Purkinje images so that no calibration for reducing person-to-person difference of cornea curvature. It is found that the proposed system allows usersf movements of 30 degrees in roll direction and 15 degrees in pitch direction utilizing detected face attitude which is derived from the face plane consisting three feature points on the face, two eyes and nose or mouth. Also it is found that the proposed system does work in a real time basis.
Toward a More Robust Usability concept with Perceived Enjoyment in the contex...Waqas Tariq
Mobile multimedia service is relatively new but has quickly dominated people¡¯s lives, especially among young people. To explain this popularity, this study applies and modifies the Technology Acceptance Model (TAM) to propose a research model and conduct an empirical study. The goal of study is to examine the role of Perceived Enjoyment (PE) and what determinants can contribute to PE in the context of using mobile multimedia service. The result indicates that PE is influencing on Perceived Usefulness (PU) and Perceived Ease of Use (PEOU) and directly Behavior Intention (BI). Aesthetics and flow are key determinants to explain Perceived Enjoyment (PE) in mobile multimedia usage.
Collaborative Learning of Organisational KnolwedgeWaqas Tariq
This paper presents recent research into methods used in Australian Indigenous Knowledge sharing and looks at how these can support the creation of suitable collaborative envi- ronments for timely organisational learning. The protocols and practices as used today and in the past by Indigenous communities are presented and discussed in relation to their relevance to a personalised system of knowledge sharing in modern organisational cultures. This research focuses on user models, knowledge acquisition and integration of data for constructivist learning in a networked repository of or- ganisational knowledge. The data collected in the repository is searched to provide collections of up-to-date and relevant material for training in a work environment. The aim is to improve knowledge collection and sharing in a team envi- ronment. This knowledge can then be collated into a story or workflow that represents the present knowledge in the organisation.
Our research aims to propose a global approach for specification, design and verification of context awareness Human Computer Interface (HCI). This is a Model Based Design approach (MBD). This methodology describes the ubiquitous environment by ontologies. OWL is the standard used for this purpose. The specification and modeling of Human-Computer Interaction are based on Petri nets (PN). This raises the question of representation of Petri nets with XML. We use for this purpose, the standard of modeling PNML. In this paper, we propose an extension of this standard for specification, generation and verification of HCI. This extension is a methodological approach for the construction of PNML with Petri nets. The design principle uses the concept of composition of elementary structures of Petri nets as PNML Modular. The objective is to obtain a valid interface through verification of properties of elementary Petri nets represented with PNML.
Development of Sign Signal Translation System Based on Altera’s FPGA DE2 BoardWaqas Tariq
The main aim of this paper is to build a system that is capable of detecting and recognizing the hand gesture in an image captured by using a camera. The system is built based on Altera’s FPGA DE2 board, which contains a Nios II soft core processor. Image processing techniques and a simple but effective algorithm are implemented to achieve this purpose. Image processing techniques are used to smooth the image in order to ease the subsequent processes in translating the hand sign signal. The algorithm is built for translating the numerical hand sign signal and the result are displayed on the seven segment display. Altera’s Quartus II, SOPC Builder and Nios II EDS software are used to construct the system. By using SOPC Builder, the related components on the DE2 board can be interconnected easily and orderly compared to traditional method that requires lengthy source code and time consuming. Quartus II is used to compile and download the design to the DE2 board. Then, under Nios II EDS, C programming language is used to code the hand sign translation algorithm. Being able to recognize the hand sign signal from images can helps human in controlling a robot and other applications which require only a simple set of instructions provided a CMOS sensor is included in the system.
An overview on Advanced Research Works on Brain-Computer InterfaceWaqas Tariq
A brain–computer interface (BCI) is a proficient result in the research field of human- computer synergy, where direct articulation between brain and an external device occurs resulting in augmenting, assisting and repairing human cognitive. Advanced works like generating brain-computer interface switch technologies for intermittent (or asynchronous) control in natural environments or developing brain-computer interface by Fuzzy logic Systems or by implementing wavelet theory to drive its efficacies are still going on and some useful results has also been found out. The requirements to develop this brain machine interface is also growing day by day i.e. like neuropsychological rehabilitation, emotion control, etc. An overview on the control theory and some advanced works on the field of brain machine interface are shown in this paper.
Exploring the Relationship Between Mobile Phone and Senior Citizens: A Malays...Waqas Tariq
There is growing ageing phenomena with the rise of ageing population throughout the world. According to the World Health Organization (2002), the growing ageing population indicates 694 million, or 223% is expected for people aged 60 and over, since 1970 and 2025.The growth is especially significant in some advanced countries such as North America, Japan, Italy, Germany, United Kingdom and so forth. This growing older adult population has significantly impact the social-culture, lifestyle, healthcare system, economy, infrastructure and government policy of a nation. However, there are limited research studies on the perception and usage of a mobile phone and its service for senior citizens in a developing nation like Malaysia. This paper explores the relationship between mobile phones and senior citizens in Malaysia from the perspective of a developing country. We conducted an exploratory study using contextual interviews with 5 senior citizens of how they perceive their mobile phones. This paper reveals 4 interesting themes from this preliminary study, in addition to the findings of the desirable mobile requirements for local senior citizens with respect of health, safety and communication purposes. The findings of this study bring interesting insight to local telecommunication industries as a whole, and will also serve as groundwork for more in-depth study in the future.
Principles of Good Screen Design in WebsitesWaqas Tariq
Visual techniques for proper arrangement of the elements on the user screen have helped the designers to make the screen look good and attractive. Several visual techniques emphasize the arrangement and ordering of the screen elements based on particular criteria for best appearance of the screen. This paper investigates few significant visual techniques in various web user interfaces and showcases the results for better understanding and their presence.
This document discusses the progress of virtual teams in Albania. It provides context on virtual teams and how they differ from traditional teams in their reliance on technology for communication across distances. The document then examines the use of virtual teams in Albania, noting the growing infrastructure and technology usage that enables virtual collaboration. It highlights some virtual team examples in Albanian government and academic projects.
Cognitive Approach Towards the Maintenance of Web-Sites Through Quality Evalu...Waqas Tariq
It is a well established fact that the Web-Applications require frequent maintenance because of cutting– edge business competitions. The authors have worked on quality evaluation of web-site of Indian ecommerce domain. As a result of that work they have made a quality-wise ranking of these sites. According to their work and also the survey done by various other groups Futurebazaar web-site is considered to be one of the best Indian e-shopping sites. In this research paper the authors are assessing the maintenance of the same site by incorporating the problems incurred during this evaluation. This exercise gives a real world maintainability problem of web-sites. This work will give a clear picture of all the quality metrics which are directly or indirectly related with the maintainability of the web-site.
USEFul: A Framework to Mainstream Web Site Usability through Automated Evalua...Waqas Tariq
A paradox has been observed whereby web site usability is proven to be an essential element in a web site, yet at the same time there exist an abundance of web pages with poor usability. This discrepancy is the result of limitations that are currently preventing web developers in the commercial sector from producing usable web sites. In this paper we propose a framework whose objective is to alleviate this problem by automating certain aspects of the usability evaluation process. Mainstreaming comes as a result of automation, therefore enabling a non-expert in the field of usability to conduct the evaluation. This results in reducing the costs associated with such evaluation. Additionally, the framework allows the flexibility of adding, modifying or deleting guidelines without altering the code that references them since the guidelines and the code are two separate components. A comparison of the evaluation results carried out using the framework against published evaluations of web sites carried out by web site usability professionals reveals that the framework is able to automatically identify the majority of usability violations. Due to the consistency with which it evaluates, it identified additional guideline-related violations that were not identified by the human evaluators.
Robot Arm Utilized Having Meal Support System Based on Computer Input by Huma...Waqas Tariq
A robot arm utilized having meal support system based on computer input by human eyes only is proposed. The proposed system is developed for handicap/disabled persons as well as elderly persons and tested with able persons with several shapes and size of eyes under a variety of illumination conditions. The test results with normal persons show the proposed system does work well for selection of the desired foods and for retrieve the foods as appropriate as usersf requirements. It is found that the proposed system is 21% much faster than the manually controlled robotics.
Dynamic Construction of Telugu Speech Corpus for Voice Enabled Text EditorWaqas Tariq
In recent decades speech interactive systems have gained increasing importance. Performance of an ASR system mainly depends on the availability of large corpus of speech. The conventional method of building a large vocabulary speech recognizer for any language uses a top-down approach to speech. This approach requires large speech corpus with sentence or phoneme level transcription of the speech utterances. The transcriptions must also include different speech order so that the recognizer can build models for all the sounds present. But, for Telugu language, because of its complex nature, a very large, well annotated speech database is very difficult to build. It is very difficult, if not impossible, to cover all the words of any Indian language, where each word may have thousands and millions of word forms. A significant part of grammar that is handled by syntax in English (and other similar languages) is handled within morphology in Telugu. Phrases including several words (that is, tokens) in English would be mapped on to a single word in Telugu.Telugu language is phonetic in nature in addition to rich in morphology. That is why the speech technology developed for English cannot be applied to Telugu language. This paper highlights the work carried out in an attempt to build a voice enabled text editor with capability of automatic term suggestion. Main claim of the paper is the recognition enhancement process developed by us for suitability of highly inflecting, rich morphological languages. This method results in increased speech recognition accuracy with very much reduction in corpus size. It also adapts Telugu words to the database dynamically, resulting in growth of the corpus.
An Improved Approach for Word Ambiguity RemovalWaqas Tariq
Word ambiguity removal is a task of removing ambiguity from a word, i.e. correct sense of word is identified from ambiguous sentences. This paper describes a model that uses Part of Speech tagger and three categories for word sense disambiguation (WSD). Human Computer Interaction is very needful to improve interactions between users and computers. For this, the Supervised and Unsupervised methods are combined. The WSD algorithm is used to find the efficient and accurate sense of a word based on domain information. The accuracy of this work is evaluated with the aim of finding best suitable domain of word. Keywords: Human Computer Interaction, Supervised Training, Unsupervised Learning, Word Ambiguity, Word sense disambiguation
Parameters Optimization for Improving ASR Performance in Adverse Real World N...Waqas Tariq
From the existing research it has been observed that many techniques and methodologies are available for performing every step of Automatic Speech Recognition (ASR) system, but the performance (Minimization of Word Error Recognition-WER and Maximization of Word Accuracy Rate- WAR) of the methodology is not dependent on the only technique applied in that method. The research work indicates that, performance mainly depends on the category of the noise, the level of the noise and the variable size of the window, frame, frame overlap etc is considered in the existing methods. The main aim of the work presented in this paper is to use variable size of parameters like window size, frame size and frame overlap percentage to observe the performance of algorithms for various categories of noise with different levels and also train the system for all size of parameters and category of real world noisy environment to improve the performance of the speech recognition system. This paper presents the results of Signal-to-Noise Ratio (SNR) and Accuracy test by applying variable size of parameters. It is observed that, it is really very hard to evaluate test results and decide parameter size for ASR performance improvement for its resultant optimization. Hence, this study further suggests the feasible and optimum parameter size using Fuzzy Inference System (FIS) for enhancing resultant accuracy in adverse real world noisy environmental conditions. This work will be helpful to give discriminative training of ubiquitous ASR system for better Human Computer Interaction (HCI). Keywords: ASR Performance, ASR Parameters Optimization, Multi-Environmental Training, Fuzzy Inference System for ASR, ubiquitous ASR system, Human Computer Interaction (HCI)
How to Setup Warehouse & Location in Odoo 17 InventoryCeline George
In this slide, we'll explore how to set up warehouses and locations in Odoo 17 Inventory. This will help us manage our stock effectively, track inventory levels, and streamline warehouse operations.
How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
How to Build a Module in Odoo 17 Using the Scaffold MethodCeline George
Odoo provides an option for creating a module by using a single line command. By using this command the user can make a whole structure of a module. It is very easy for a beginner to make a module. There is no need to make each file manually. This slide will show how to create a module using the scaffold method.
This presentation includes basic of PCOS their pathology and treatment and also Ayurveda correlation of PCOS and Ayurvedic line of treatment mentioned in classics.
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
Main Java[All of the Base Concepts}.docxadhitya5119
This is part 1 of my Java Learning Journey. This Contains Custom methods, classes, constructors, packages, multithreading , try- catch block, finally block and more.
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
The simplified electron and muon model, Oscillating Spacetime: The Foundation...RitikBhardwaj56
Discover the Simplified Electron and Muon Model: A New Wave-Based Approach to Understanding Particles delves into a groundbreaking theory that presents electrons and muons as rotating soliton waves within oscillating spacetime. Geared towards students, researchers, and science buffs, this book breaks down complex ideas into simple explanations. It covers topics such as electron waves, temporal dynamics, and the implications of this model on particle physics. With clear illustrations and easy-to-follow explanations, readers will gain a new outlook on the universe's fundamental nature.
The simplified electron and muon model, Oscillating Spacetime: The Foundation...
V/F Control of Squirrel Cage Induction Motor Drives Without Flux or Torque Measurement Dependency
1. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 77
V/F Control of Squirrel Cage Induction Motor Drives Without
Flux or Torque Measurement Dependency
Walid Emar walidemar@yahoo.com
Electrical Engineering Department
Isra University
11622 Amman, Jordan
Hussein Sarhan hussein_52@hotmail.com
Mechatronics Engineering Department
Balqa’ Applied University
Amman, Jordan
Rateb Al-Issa ratebissa@yahoo.com
Mechatronics Engineering Department
Balqa’ Applied University
Amman, Jordan
Issam TTrad Issam_161@yahoo.com
Faculty of science and information
Jadara University
Irbid, Jordan
Mahmoud Awad Dr_Awad_M@yahoo.com
Electrical Engineering Department
Balqa’ Applied University
Amman, Jordan
Abstract
Based on the popular constant volts per hertz principle, two improvement techniques are
presented: keeping maximum torque constant or keeping magnetic flux constant. An open-
loop inverter-three-phase squirrel-cage induction motor drive system that provides constant
maximum torque or increased maximum torque and reduced slip speed at frequencies below
the nominal frequency has been modeled, simulated and tested. Load performance analysis
of the proposed system under different operation conditions was provided. These principles of
operation are extended to the case of operation from variable frequency or variable voltage
control method. Finally, the effects of the non-sinusoidal voltage and/or current wave shapes
are covered.
The results show that both suggested improvement techniques (constant torque or constant
flux) improve the steady-state performance A.C. drive system with squirrel cage induction
motors. The slip speed has been decreased and the starting torque and maximum torque
have been increased, which means that the suggested control techniques can be used in
drive systems with short time operating mode under light loads.
Keywords: Induction Motor Drive, Constant Volts Per Hertz, Torque Speed Curve, dq
Transformation, State-space Model.
Nomenclature:
=dsv d-axis component of the stator voltage, V
=qsv q-axis component of the stator voltage, V
=dsi d-axis component of the stator current, A
=qsi q-axis component of the stator current, A
=dri' d-axis component of the rotor current referred to the stator, A
2. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 78
=qri' q-axis component of the rotor current referred to the stator, A
V or Vs = stator voltage effective value
=sL stator inductance, H
=rL' rotor inductance referred to the stator, H
=mL mutual inductance between rotor and stator, H
msss LLL += , H
mrrr LLL += '' , H
=sω stator electrical angular speed, rad/s
=rω rotor electrical angular speed, rad/s
rm
P
ωω
2
= , rotor mechanical angular speed, rad/s
=P number of poles
=eT electromagnetic developed torque, N.m
=mT load torque, N.m
=J equivalent moment of inertia, kg.m
2
1. INTRODUCTION
The three-phase squirrel cage induction motor is the most widely used motor type in the
industry because of its good self-starting capability, simple and rugged structure, low cost and
reliability [1-5]. In spite of this popularity, the induction motor has two basic limitations: (1) The
standard motor is not a true constant-speed machine, its full-load slip varies from less than
1% (in high-horsepower motors) to more than 5% (in fractional-horsepower motors), and (2) It
is not inherently capable of providing variable-speed operation [2,3]. Both of these limitations
require consideration to meet quality and accuracy requirements of induction motor drive
applications.
The limitations of induction motor can be solved through the use of adjustable speed control
based on pulse width modulation techniques [4]. The basic control action involved in
adjustable speed control of induction motors is to apply a variable frequency variable
magnitude AC voltage to the motor to achieve the aims of variable speed operation [5].
Voltage source inverters and current source inverters are used in adjustable speed AC drives.
However, voltage source inverters with constant Volts/Hertz (V/f) are more popular, especially
for applications without position control requirements, or where the need for high accuracy of
speed control is not crucial.
Ideally, by keeping a constant V/f ratio for all frequencies the torque-speed curve of induction
motor can be reproduced at any frequency. In this case, the stator flux, stator current, and
torque will be constant at any frequency [6]. The great majority of variable-speed drives in
operation today are of this type although almost all research has been concentrated in field-
oriented control theory, and little has been published about constant V/f operation. Its
practical application at low frequency is still challenging, due to the influence of the stator
resistance and the necessary rotor slip to produce torque [7].
In addition, the nonlinear behavior of the pulse-width modulated voltage-source inverter in the
low voltage range makes it difficult to use constant V/f drives at frequencies below 3Hz [8, 9].
The performance of induction motor operating at constant V/f ratio can be improved by using
different techniques, such as stator resistance compensation, slip compensation and vector
compensation. The stator resistance compensation method consists of boosting the stator
voltage by the magnitude of the current-resistance drop. Slip compensation results in
increasing the operating frequency (speed). Vector compensation requires measurement of
both voltage and current and accurate knowledge of machine inductances [10].
3. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 79
In this paper, two techniques to improve the performance of the inverter-induction motor drive
system with constant V/f ratio controller are presented. The first technique is based on
keeping the maximum torque constant for all operating frequencies, and equals to its value at
nominal frequency. The second technique is based on maintaining the magnetic flux constant
at all operating frequencies and equals to its nominal value. The proposed techniques are
validated by simulation and experimental results. It is shown that large load torques are
obtained, even in the low frequency range, with significantly reduced steady-state error in
speed.
These principles of operation are extended to the case of operation from variable frequency
and/or variable voltage control method. Finally, the effects of the non-sinusoidal voltage
and/or current wave shapes are covered.
2. MODELING SYSTEM COMPONENTS
The block diagram of inverter-three-phase squirrel cage induction motor drive system is
presented in figure 1. It consists of IGBT-inverter-based AC to AC converter, three-phase
squirrel cage induction motor and controller. In order to analyze the system performance, all
of these components should be modeled (mathematically described).
FIGURE 1: Block diagram of inverter-three phase squirrel-cage induction motor drive system
2.1. Modeling of the IGBT-Inverter-Based AC to AC Converter
The frequency converter is considered to be an ideal system, where the voltage at the dc side
of the converter has no AC component. For sinusoidal pulse width modulation SPWM, the
ratio of the amplitude of the sinusoidal waveform to the amplitude of the triangular waveform
is called the modulation index m, which can be in the range of 0 to 1 [11]. The stator voltage
Vs can be defined as:
Vs = m Vn (1)
Where:
Vn = nominal value of stator voltage.
The frequency of the stator voltage f equals the frequency of the sinusoidal input waveform fin.
f = fin (2)
4. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 80
FIGURE 2: Steady-state model of inverter.
Varying the modulation index and the sinusoidal waveform frequency will change the RMS
value of the stator voltage and frequency. Eqs. 1 and 2 constitute the steady-state model of
inverter, shown in figure 2.
2.2. Modeling of Controller and Control Circuits
Based on the principle of V/f = constant, the controller must apply the following function:
≥
<<
=
n
n
ff
ffKf
m
,1
0,
(3)
Where:
K = 1/fn, and fn = nominal frequency (50Hz). The block diagram of V/f = constant controller is
shown in figure 3.
FIGURE 3: The model of V/f = constant controller.
Control circuits of A.C. drive system with induction motor can be divided according to different
criterions. The following thinking will be focused on the fundamental properties of electric
drives which are different from each other by the way of setting the required stator voltage of
the motor:
1. Variant 1: The desired voltage may be measured and evaluated by using a suitable
controller, “RI” shown in figure 4a.
5. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 81
FIGURE 4A: Variant 1.
Under the effect of the variation of the load torque, the stator voltage may behave just like a
disturbance that is applied to the control system. Therefore, if the current-controller, RI, is
working well, then any change in the load torque will not affect the function of the motor which
means that there is no need for a voltage feedback from the capacitor connected at the d.c.
side of the rectifier as shown in figure 4a.
2. Variant 2: The stator voltage is simply estimated.
FIGURE 4B: Variant 2.
If the estimated voltage has to be equal exactly to the actual stator voltage even after it is
changed, then it is necessary to take into consideration the voltage feedback from the
capacitor as shown in Fig. 4b.
2.3.Modeling of Three-Phase Squirrel Cage Induction Motor
Many studies of the transient and steady state performance of induction motors have used
two axes (d-q) dynamic machine model for the solution of the motor performance equations
[12], while other studies have used a direct three-phase dynamic model that seemed more
convenient, due to the variables involved in such modeling, in which they are the actual
physical quantities of the motor [13]. Some authors have used dynamic model for small
perturbations and transfer function, or solutions for dynamic behavior in complex symbolic
form [14].
The steady state performances of the induction motors are obtained using static model
6. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 82
equations, derived from a dynamic model by setting their derivatives to zero and solving the
resulting motor equations for the motor variables.
The state-space model of the squirrel cage three-phase induction motor in standard form,
with respect to a synchronously rotating d-q coordinates, can be expressed as[15, 16]:
+=
+=
•
DuCxy
BuAxx (4)
Where the matrix quantities in Eq. 4 are as follows:
T
mqrqsdrds iiii
=
••••••
ω''x -state equations vector
[ ]T
mqrqsdrds iiii ω''=x -state vector
[ ]T
emqrqsdrds Tiiii ω''=Y -output vector
[ ]mqsds Tvv 00=u -input vector
[ ]0=D -direct transmission matrix
FIGURE 5: State-space model of induction motor.
7. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 83
−
+−−
−−−
−−−−
−+
=
00
'
0
'
0
2'2'
'
0
'
'
2'2
0
22
'
0
'
22
111
2
2
1
1
2
2
1
11
122
2
1
1
2
2
1
1
12
J
iL
J
iL
K
P
L
L
K
P
K
L
R
K
L
R
K
L
R
K
L
R
K
P
L
L
K
P
L
L
K
P
K
P
K
L
R
K
L
R
K
L
R
K
L
R
L
L
K
P
K
P
drmqrm
ms
rr
m
m
rrm
rrm
ms
rr
m
m
ss
m
mms
mss
mssss
m
mms
αα
ωωω
ωωω
ωωω
ωωω
A -state matrix
−
−
−
−
−
=
J
L
K
L
K
L
K
L
K
L
K
L
K
L
K
L
K
rrm
rrm
mss
mss
1
0000
0
'
00
00
'
0
000
000
12
12
21
21
B -input matrix
−
=
00'0'
10000
01000
00100
00010
00001
drmqrm iLiL αα
C -output matrix
P
4
3
=α -constant;
mrrss
rrss
LLL
LL
K 21
'
'
−
= -constant;
mrrss LLL
mL
K 2
2
2
' −
= -constant
The model of mechanical part of an induction motor can be represented by:
mme JTT
•
=− ω (5)
Where the electromagnetic torque Te is expressed as:
)''(
4
3
qrsddrqsme iiiiPLT −= (6)
Inputting Eq. 8 into Eq. 7, we get:
mqrds
m
drqs
m
m T
J
ii
J
PL
ii
J
PL 1
'
4
3
'
4
3
−−=
•
ω (7)
The state-space model of induction motor as electromechanical system is shown in figure 5.
The parameters of simulated induction motor are given in table 1. The block diagram of the
drive system studied using MATLAB Simulink is shown in figure 6.
8. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 84
It was noticed also that the absolute slip decreased by decreasing the frequency. The
absolute slip defined as:
n
m
as
0
0
ω
ωω −
= (8)
Where:
0ω is the no-load speed at a given frequency and n0ω is the no-load at nominal frequency.
FIGURE 6: The model of the drive system.
2.4. Control With Constant Maximum Torque
The maximum torque at nominal frequency )max(nT can be determined by the following
equation [10]:
)(8
3
2
1
2
1
2
)max(
synn
n
XRRf
nPV
T
++
=
π
(9)
Where:
nV = nominal value of stator voltage (phase), nf = nominal frequency, and
)'(2'21 rsnsyn LLfXXX +=+= π
The maximum torque maxT at any frequency f can be determined as:
))'22(((8
3
2
1
2
1
2
max
rs fLfLRRf
PV
T
πππ +++
= (10)
Equating Esq. 9 and 10, we get:
syn
syn
nn
nn
s
n XRR
XR
f
f
R
f
f
f
f
V
V
V
V
m
2
1
2
1
2
1
22
1 )(
++
++
== (11)
Equation 11 shows that the value of the modulation index m generated for the controller with
constant maximum torque is greater than that generated for the controller with
constant/ =fV . The model of constantmax =T controller is shown in figure 7.
The simulated mechanical characteristics of the drive system with constantmax =T controller
are shown in figure 8, from which it is clear that the maximum torque remains constant for the
9. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 85
frequency range from 20Hz up to 50Hz. For frequencies below 20Hz the maximum torque has
been significantly increased comparing with that of the drive system with constant/ =fV
controller. The absolute slip has been decreased.
FIGURE 7: The model of constantmax =T controller.
FIGURE 8: Mechanical characteristics of drive system with Tmax= constant controller
Parameter Value
Stator resistance R1 65
Stator reactance X1 40
Mutual reactance Xm 241
Rotor resistance referred to the stator R'2 25
Rotor reactance referred to the stator X'2 30
Nominal voltage Vn 230/400V
Nominal torque Tn 1.3N.m
Nominal input power Pn 0.25kW
Nominal current In 0.76A
Power factor 0.79
Nominal frequency fn 50Hz
Number of poles P 4
Nominal speed nn 1455 rpm
Nominal angular speed 152 rad/s
Moment of inertia J 0.02 kg.m
2
TABLE 1: Motor parameters
10. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 86
2.5. Control With Constant Flux
The stator flux can be kept constant, and equal to its nominal value, if the ratio of the
magnetizing e.m.f. Em to the stator frequency f remains constant, )(
n
mnm
f
E
f
E
= . Under this
condition, and based on the induction motor steady-state equivalent circuit and phasor
diagram, the stator voltage V can be determined as:
msfV IIRKV 22
1/ −+= (12)
Where:
constant/ ==
f
V
K fV , mI = magnetizing (no-load) current.
Eq. 12 shows that the stator voltage V in the case of controller with constant flux is always
greater than that of constant/ =fV controller. The model of controller with constant flux is
shown in figure 9.
FIGURE 9: The model of φ = constant controller.
3. SIMULATION RESULTS
The Performance analysis of the drive system with fV controller was provided for different
values of frequency and load torque. The magnetization curve of the motor is given as
follows:
)( mh If=Ψ :
( )
576,0.96422,0.9,311,0.83,229,0.76,151,0.7,32,0.63,101,0.56,1
80,0.5,63,0.45,60,0.38,39,0.31,29,0.24,0,0,: =hmI ψ
Examples of dynamic response of the system are shown in the following figures. Simulated
mechanical characteristics of the drive system with different types of controllers are
represented in figure 10, which shows that decreasing the frequency causes a significant
increase in the maximum torque in the case of a controller with constant flux.
Figure 11 shows that the absolute slip is reduced and less than that of other types of
controllers. The obtained mechanical characteristics of the drive system with constant flux
controller are similar to those of drive system operating with constant power.
11. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 87
FIGURE10: Mechanical characteristics of drive system with different types of controllers.
FIGURE11: Experimental mechanical characteristics of drive system with different types of controllers.
Figure (12) shows the plot of the stator voltage space vector versus the stator current space
vector, Us versus Is, the plot of the developed torque, eT , and the r.m.s. value of the stator
current, Isef versus the rotor frequency, fr.
12. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 88
FIGURE 13: a plot of (a) Vs, Is …abs. value of space vectors in time domain
Figure 13 shows the stator voltage and current space vectors, Us and Is, under the condition
of a variable stator voltage and constant rotor frequency. The response of the system on a
change in the stator voltage while the rotor frequency is constant is adversely bad.
The results show that both the absolute value of the space vector of the stator current and the
motor torque, eT , increase with the increasing rotor frequency. The motor was not able to start
at frequencies below 22Hz at load of 1.0N.m and below 11Hz at load of 0.5N.m. It was
noticed also that the absolute slip, defined as
n
m
s
0
0
ω
ωω −
= , is decreased with the decreasing
frequency, where 0ω is the no-load speed at a given frequency and n0ω is the no-load at
nominal frequency. Variation of frequency does not have significant effect on the steady-state
value of stator current. Similar results were reported in [10, 11].
Therefore, if the voltage is set at the output of the controller (e.g. current), then it will cause
some serious problems: during breaking regime and after reducing the voltage as it is seen in
figure 13, an overshoot in the stator current is generated which is considered to be a currently
known phenomenon. It could be explained by using an equivalent schematic diagram which
respects the induced voltage in the stator circuit,
dt
dψ
and that in the rotor circuit,
dt
d
s
ψ1
.
The simulation in figure 14 is carried out for a variable rotor frequency and constant voltage.
The response to a step change in the rotor frequency is completely trouble free as it is shown
in the figure. The frequency of the rotor may easily be evaluated by using a controller of any
quantity, for example (e.g. Siemens, Simovert P … fr is evaluated by using a controller of the
torque component).
In order to improve the starting and load performance of the drive system under the effect of
stator voltage variations, a filter is added at the output of the current controller which may
have a bad effect on the dynamic properties of the current loop, especially if the loop contains
further blocks with expected delay in the response. Therefore, the stator voltage Vs is set
using a limiter at the output of the controller and a PI controller (KRI, TRI) must be added as
13. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 89
shown in figure 15. When the voltage decreases, the PI controller reduces the firing angle.
When the voltage increases, the PI controller increases the firing angle.
FIGURE 12: a plot of : (a) torque Te versus rotor frequency. (b) Vs versus Is …absolute values of space
vectors.
14. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 90
FIGURE 14: Isd, Isq … direct and quadrature components of stator current vector, Te … developed
torque, Fh …magnetomotive force.
FIGURE 15: Improved control schematic topology
fr = 0.6 Hz, ω=2.π.40, KRI = 2, TRI = 0.2 s, TFI = 0, Is …absolute values of space vectors.
fr = -0.6 Hz, ω=2.π.40, KRI = 2, TRI = 0.2 s, TFI = 0.
15. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 91
fr = -0.6 Hz, ω=2.π.40, KRI = 0.2, TRI = 0.5 s, TFI = 0, (small gain , without a filter).
FIGURE 16: Improved simulation results, Isw: desired r.m.s. value of Is.
In the AC motor drive, the motor speed is not regulated in closed loop. Instead, the speed set
point is used only to determine the motor voltage and frequency applied by the six-step
inverter in order to maintain the (V/f) ratio (or the motor flux) constant from 0 to the nominal
speed. Above nominal speed, the motor operates in the flux weakening mode; that is, the
voltage is maintained constant at its nominal value while the frequency is increased
proportionally to the speed set point. When reversing speed, a short delay is required at the
zero speed crossing so that air gap flux decays to zero.
Under the above mentioned improvement conditions, figure 16 shows an improved simulation
carried out for different values of rotor frequency and controller parameters.
4. CONCLUSION
Based on the results obtained in this paper, the following conclusions can be made:
1. The derived state-space model of three-phase squirrel cage induction motor can be
used to analyze the performance of induction motor drive systems.
2. The implementation of constant maximum torque and constant flux controllers
improves the performance of inverter-induction motor drive systems.
3. The mechanical characteristics of the drive system with constant flux controller are
harder than that with constant maximum torque controller.
4. It is recommended to use constant maximum torque controller in drive systems
operating with constant torque.
5. It is recommended to use constant flux controller in drive systems operating with
constant power.
5. REFERENCES
[1]. R.W. De Doncker, D. W. Novonty. "The Universal Field Oriented Controller," IEEE
Trans. Ind. Applicat., vol. IA-30, No 1, 1994, pp. 92-100.
[2]. R.D. Lorentz, T.A. Lipo and D.W. Novotny. "Motion Control with Induction Motors,"
Proceedings of IEEE, vol. 82, No. 8, 1994, pp. 1215-1240.
[3]. O.I. Okogo. "MATLAB Simulation of Induction Machine with Saturable Leakage and
Magnetizing Inductances," The Pacific Journal of Science and Technology, vol. 5, No. 1,
April 2003 (Spring), pp. 5-15.
[4]. A.E. Fitzgerald. " Electric Machinery," 5
th
Ed., McGraw-Hill, 1990.
[5]. R. Gabriel, and W. Leonhard. "Microprocessor Control of Induction Motor," IEEE/IAS Int.
Sem. Power Conv. Conf. Rec., 1982, pp. 385-396.
16. Walid Emar, Hussein Sarhan, Rateb Al-Issa, Issam TTrad & Mahmoud Awada
International Journal of Robotics and Automation (IJRA), Volume (2) : Issue (2) : 2011 92
[6]. R. Marino, S. Peresada, and P. Valigi. "Adaptive Input-Output Linearizing Control of
Induction Motors," IEEE Trans. Autom. Cont., vol. 38, No. 2, 1993, pp. 208-221.
[7]. Hussein Sarhan, Rateb Al-Issa, and Qazem Jaber. "Loss-Minimization Control of Scalar
Controlled Induction Motor Drives," 4th
IEEE GCC Conference and Exhibition, Manama,
Kingdom of Bahrain, 12th
-14th
Nov., 2007, p. 64.
[8]. K. Zhou and D. Wang. "Relationship Between space-Vector Modulation and Three-
phase Carrier-Based PWM: A Comprehensive Analysis," IEEE Trans. Ind. Electronics,
vol. 49, No. 1, 2002, pp. 186-195.
[9]. B.K. Bose. "Power Electronics and Variable Frequency Drives," IEEE Press, 1997, p.
402.
[10]. M.G. Alfredo, A.L. Thomas, and W.N. Donald. "A New Induction Motor V/f Control
Method Capable of High-Performance Regulation at Low Speeds," IEEE Trans. Ind.
Applicat., vol. 34, No. 4, July-august, 1998, pp. 813-820.
[11]. R. Sepe and J. Lang. "Inverter Nonlinearities and Discrete-Time Vector Current
Control," IEEE Trans. Ind. Applicat., vol. 30, Jan.-Feb., 1994, pp. 62-70.
[12]. M.A. Ouhrouche. "Simulation of Direct Field-Oriented Controller for an Induction Motor
Using MATLAB-Simulink Software Package," Proceedings of the IASTED International
Conference Modeling and simulation, May 15-17, 2000-Pittsburgh, Penn
1
sylvania, USA.