Switched Reluctance Motor is an old member of Electrical Machines Family.It’s
simple structures and ruggedness and inexpensive manufacturing capability make it more
attractive for industrial application. However these merits are overshadowed by inherent
high torque ripple, acoustic noise and difficulty to control. In proposed converter, the
hysteresis
current control technique is applied
for analysis of three phase 6/4
Switched Reluctance motor. Using this technique ,torque, current, and flux linkage speed
curves of SRM are obtained at no load and load condition by MATLAB /SIMULINK.
Index Terms—
1) A new converter topology for closed loop speed control of a switched reluctance motor is proposed, consisting of half-bridge IGBT modules and SCRs.
2) The proposed converter topology aims to improve upon the conventional asymmetric bridge converter by enhancing utilization of switching devices.
3) Simulation results in MATLAB/Simulink validate the operation of the proposed converter topology in both open loop and closed loop configurations for driving a switched reluctance motor.
This paper presents the review of design variables optimization and control strategies of a Linear Switched Reluctance Actuator (LSRA). The introduction of various type of linear electromagnetic actuators (LEA) are compared and the advantages of LSRA over other LEA are discussed together with the type of actuator configurations and topologies. The SRA provides an overall efficiency similar to induction actuator of the similar rating, subsequently the friction and windage losses are comparable but force density is better. LSRA has the advantage of low cost, simple construction and high reliability compare to the actuator with permanent magnet. However, LSRA also has some obvious defects which will influence the performance of the actuator such as ripples and acoustic noise which are caused by the highly nonlinear characteristics of the actuator. By researching the design variables of the actuator, the influences of those design variables are introduced and the detail comparisons are analyzed in this paper. In addition, this paper also reviews on the control strategies in order to overcome the weaknesses of LSRA.
This document describes a double-rotor switched reluctance machine (DRSRM) that could be used as a hybrid electric vehicle powertrain. A DRSRM contains two rotors and one stator within a single machine housing. The two rotors can be independently operated and controlled, allowing the machine to output power and torque from two independent drive shafts. This integrated design is potentially more compact, lower cost, and enables two mechanical outputs suitable for hybrid electric transmissions. The document outlines the configuration, design, simulation, optimization, and testing of a DRSRM prototype.
special electrical motor(switched reluctance motor)Srihari Datta
Switched reluctance motors have several advantages over traditional motors, including a simple and robust structure without windings or permanent magnets on the rotor. Torque is produced through the tendency of the rotor poles to align with excited stator poles. The motor has a doubly salient pole structure and nonlinear magnetic characteristics, which can cause torque ripple problems. The motor consists of concentrated stator coils and no coils or magnets on the rotor. Multiple stator/rotor pole combinations are possible. Torque is produced by controlling the timing of current pulses in the stator phases using power electronics. The motor can operate over a wide speed range at high efficiency using various control strategies to regulate the current pulses.
This document discusses variable switch reluctance motors (VSRM). It describes the basic components and operation of a VSRM, including how torque is produced through energizing winding pairs in a precise sequence. The document also compares VSRMs to other motor types and discusses their advantages like low material cost and ability to be precisely programmed to match different loads. Control of VSRMs requires switching winding excitation on and off using techniques like advanced DSP control schemes. Both advantages and shortcomings of VSRMs are examined.
Different type s of power converters fed relutanceSambit Dash
This document presents a comparison of six converter types for a 3-phase 6/4 switched reluctance motor (SRM). It summarizes the operation and simulation results of R-dump, C-dump, C-dump with freewheeling transistor, asymmetric, series, and parallel converters. The asymmetric bridge converter is identified as best for high speeds due to its fast current fall and rise times. Motor parameters and conclusions are also provided in less than 3 sentences.
This document analyzes linear switched reluctance motors (LSRM). It begins by describing conventional switched reluctance motors (SRM) and their working principles. It then discusses the construction, working, and advantages of LSRM compared to SRM. Key differences between SRM and LSRM are that LSRM provide linear motion rather than rotational motion and have higher efficiency and power density. The document also covers applications of SRM and concludes by listing topics to be covered in a future review.
1) A new converter topology for closed loop speed control of a switched reluctance motor is proposed, consisting of half-bridge IGBT modules and SCRs.
2) The proposed converter topology aims to improve upon the conventional asymmetric bridge converter by enhancing utilization of switching devices.
3) Simulation results in MATLAB/Simulink validate the operation of the proposed converter topology in both open loop and closed loop configurations for driving a switched reluctance motor.
This paper presents the review of design variables optimization and control strategies of a Linear Switched Reluctance Actuator (LSRA). The introduction of various type of linear electromagnetic actuators (LEA) are compared and the advantages of LSRA over other LEA are discussed together with the type of actuator configurations and topologies. The SRA provides an overall efficiency similar to induction actuator of the similar rating, subsequently the friction and windage losses are comparable but force density is better. LSRA has the advantage of low cost, simple construction and high reliability compare to the actuator with permanent magnet. However, LSRA also has some obvious defects which will influence the performance of the actuator such as ripples and acoustic noise which are caused by the highly nonlinear characteristics of the actuator. By researching the design variables of the actuator, the influences of those design variables are introduced and the detail comparisons are analyzed in this paper. In addition, this paper also reviews on the control strategies in order to overcome the weaknesses of LSRA.
This document describes a double-rotor switched reluctance machine (DRSRM) that could be used as a hybrid electric vehicle powertrain. A DRSRM contains two rotors and one stator within a single machine housing. The two rotors can be independently operated and controlled, allowing the machine to output power and torque from two independent drive shafts. This integrated design is potentially more compact, lower cost, and enables two mechanical outputs suitable for hybrid electric transmissions. The document outlines the configuration, design, simulation, optimization, and testing of a DRSRM prototype.
special electrical motor(switched reluctance motor)Srihari Datta
Switched reluctance motors have several advantages over traditional motors, including a simple and robust structure without windings or permanent magnets on the rotor. Torque is produced through the tendency of the rotor poles to align with excited stator poles. The motor has a doubly salient pole structure and nonlinear magnetic characteristics, which can cause torque ripple problems. The motor consists of concentrated stator coils and no coils or magnets on the rotor. Multiple stator/rotor pole combinations are possible. Torque is produced by controlling the timing of current pulses in the stator phases using power electronics. The motor can operate over a wide speed range at high efficiency using various control strategies to regulate the current pulses.
This document discusses variable switch reluctance motors (VSRM). It describes the basic components and operation of a VSRM, including how torque is produced through energizing winding pairs in a precise sequence. The document also compares VSRMs to other motor types and discusses their advantages like low material cost and ability to be precisely programmed to match different loads. Control of VSRMs requires switching winding excitation on and off using techniques like advanced DSP control schemes. Both advantages and shortcomings of VSRMs are examined.
Different type s of power converters fed relutanceSambit Dash
This document presents a comparison of six converter types for a 3-phase 6/4 switched reluctance motor (SRM). It summarizes the operation and simulation results of R-dump, C-dump, C-dump with freewheeling transistor, asymmetric, series, and parallel converters. The asymmetric bridge converter is identified as best for high speeds due to its fast current fall and rise times. Motor parameters and conclusions are also provided in less than 3 sentences.
This document analyzes linear switched reluctance motors (LSRM). It begins by describing conventional switched reluctance motors (SRM) and their working principles. It then discusses the construction, working, and advantages of LSRM compared to SRM. Key differences between SRM and LSRM are that LSRM provide linear motion rather than rotational motion and have higher efficiency and power density. The document also covers applications of SRM and concludes by listing topics to be covered in a future review.
1) The document discusses models for permanent magnet motor drives, specifically the permanent magnet synchronous motor (PMSM) and brushless DC motor (BDCM).
2) It explains that the PMSM has a sinusoidal back EMF and requires sinusoidal currents, while the BDCM has a trapezoidal back EMF and requires rectangular currents.
3) The paper argues that a d-q axis model is suitable for modeling the PMSM, while an ABC phase variable model should be used for the BDCM due to its non-sinusoidal inductances.
The document discusses vector control of permanent magnet synchronous motors (PMSM). It begins by describing the dynamic model of a PMSM, including assumptions made about the rotor flux. It then derives the stator equations in the rotor reference frame to model the PMSM similarly to an induction motor. Vector control of the PMSM is then derived from its dynamic model to decouple the torque and flux channels by controlling the stator currents in the d-q reference frame. This allows controlling the PMSM similarly to a separately excited DC motor.
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.
Mathematical Modelling of an 3 Phase Induction Motor Using MATLAB/Simulink IJMER
Mechanical energy is needed in the daily life use as well as in the industry. Induction motors
play a very important role in both worlds, because of low cost, reliable operation, robust operation and low
maintenance. To derive the mathematical model of a 3 phase Induction motor, the theory of reference
frames has been effectively used as an efficient approach. Dynamic models (mathematical models) are
employed in to better understand the behaviour of induction motor in both transient and steady state. The
dynamic modelling sets all the mechanical equations for the inertia, torque and speed versus time. It also
models all the differential voltage, currents and flux linkages between the stationary stator as well as the
moving rotor. This paper presents a step by step Matlab/Simulink implementation of an induction machine
using dq0 axis transformations of the stator and rotor variables in the arbitrary reference frame [1].
In recent years, Permanent Magnet Synchronous Machines (PMSMs) are increasing
applied in several areas such as generation, traction, automobiles, robotics and aerospace
technology. Basically PMSG topology has been beneficial for slow speed and variable speed
operation and steady state output power produced in operation. PMSG is a part of
synchronous machine family, so its construction features almost equivalent to synchronous
machine.
With respect of designing a PMSG, the permanent magnetic pole lies on the rotor and
armature winding are in the inner part of stator that is electrically connected to the load.
Armature winding consists of the set of three conductors which has phase difference 1200
apart to each other and providing a uniform force or torque on the generator’s rotor. To
operate PMGS, it is connected to wind turbine through a shaft without gear box and rotate at
slow speed. This uniform torque produced by the resultant magnetic flux which induces
current in the armature winding. The stator magnetic field combined spatially with rotor
magnetic flux and rotates as the same speed of the rotor. So the two magnetic fields
synchronously rotate in PGSM to maintain the relative motion of rotor and stator.
Thus the permanent magnets rotates at constant speed without any DC excitation system,
which means it has not required any slip rings and contact brushes to make it more reliability
or efficient.
This paper is intended to study and compare the operation of two methods for estimating the position/ speed of the permanent magnet synchronous motor (PMSM) under sliding mode control. The first method is a model reference adaptive system (MRAS). The second method based on sliding mode observer (SMO). The stability condition of Sliding Mode Observer was verified using the Lyapunov method to make sure that the observer is stable in converging to the sliding mode plane. In this paper the performances of the proposed two algorithms are analyzed using SIMULINK/MATLAB. The simulations results are presented to verify the proposed sensorless control algorithms and can resolve the problem of load disturbance effects by simulations which verify that the two closed-loop control system is robust with respect to torque disturbance rejection.
Design of a wind power generation system using a permanent magnet synchronous...eSAT Journals
Abstract This paper presents a wind power system using a Permanent Magnet Synchronous Machine (PMSM). The whole system consists of a wind turbine, a permanent magnet synchronous machine, a three phase diode rectifier, a boost converter, a transformer-less step down circuit, an H-bridge inverter and a T-LCL filter. The 3-phase AC output from the PMSM is sent to the 3-phase diode rectifier for conversion to DC and a boost regulator is used to step-up this DC voltage to the desired level. This step-upped DC voltage is then converted into AC output by the H-Bridge inverter. The switching technique of the proposed inverter consists of a combination of Sinusoidal Pulse Width Modulation (SPWM) and a square wave along with grid synchronization conditions. As the suggested method is entirely transformer-less, it significantly reduces Total Harmonic Distortion (THD) to less than 0.1% and minimizes its size. The T-LCL Immittance Converter not only reduces the harmonics of the inverter output but also provides a nearly constant output current thereby stabilizing the system. The system setup and the simulation results were obtained using the PSIM software. Keywords: Wind Turbine, Permanent Magnet Synchronous Machine, Boost Converter, Step- down Circuit, T-LCL Immittance Converter, Inverter
This ppt shows the modelling and simulation of permanent magnet synchronous motor by using torque control method.
And this is the most advanced and soffestigated method to control the pmsm motors.
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
Induction Motor Tests Using MATLAB/SimulinkGirish Gupta
This project describes MATLAB/Simulink implementation of three induction motor tests, namely DC, No-Load, and Blocked-Rotor tests which are performed to identify equivalent circuit parameters of an Induction Machine. These simulation models are developed to support and enhance electric machinery education at the undergraduate level.
Hardware implememtation of open end winding based multi levelsuvarnadasan
This document describes a project to implement an open-end winding based multilevel inverter. The project aims to drive a three-phase induction motor using two dual 2-level inverters. By opening the neutral point of the stator windings and feeding both sides with separate inverters, 3-level inversion is achieved. The basic circuit uses two 2-level inverters to generate pole voltages that result in stepped phase voltages to drive the motor. This provides improved power quality over conventional 2-level inverters.
This document summarizes research on techniques to minimize torque ripple in switched reluctance motors (SRM). It discusses that torque ripple is inherent in SRM due to their doubly salient structure. It reviews two main approaches: 1) Improving the magnetic design of the motor and 2) Using sophisticated electronic control techniques like indirect torque control methods using torque sharing functions or direct torque control. Indirect methods involve converting torque references to current references using look-up tables, while direct methods estimate torque directly from stored profiles. The document surveys literature on different torque sharing functions and controllers like hysteresis control and sliding mode control that can be used to optimize control parameters and minimize torque ripple.
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.
Torque Production & Control of Speed in Synchronous Motor.
Speed of synchronous motors can be controlled using two methods called open loop and close loop control.
Open loop contol is the simplest scalar control method where motor speed is controlled by independent frequency control of the converter.
In case of close loop self control mode, instead of controlling the inverter frequency independentaly, the frequency and the phase of the output waveform are controlled by an absolute position encoder mounted on the machine shaft giving an account of position of the rotor.
This document discusses direct current (DC) motors. It describes the construction and operating principles of different types of DC motors including series, shunt, compound and permanent magnet motors. It also discusses speed control methods for shunt and separately excited DC motors. The main methods of speed control are armature voltage control, field control and armature resistance control. Armature resistance control is simple but less efficient while field control provides better speed regulation.
This document discusses the theory and experimental procedures for determining the load characteristics of DC shunt, series, and compound motors. The experiments involve constructing circuits for each motor type and measuring speed, current, torque, power, and efficiency at increasing loads. Load characteristics such as speed regulation, starting torque, and efficiency are then determined and compared between motor types from the experimental results.
This document provides reading material on DC machines for electrical engineering students. It covers the basic principles of operation and torque equations for DC motors. It describes the operating characteristics such as speed-current, torque-current and speed-torque curves for shunt and series motors. It discusses starting methods such as 2-point, 3-point and 4-point starters. Methods of speed control including armature resistance, field flux and armature voltage control are explained. The document also covers losses, efficiency testing and applications of DC machines.
This document summarizes a paper that models and simulates a switched reluctance motor (SRM) to minimize torque ripple through different converter topologies and control strategies. The paper develops a mathematical model of a 6/4 SRM in Matlab/Simulink. It simulates the motor with asymmetric, Miller, and modified Miller converters. Torque ripple is evaluated using power spectrum density analysis. The modified Miller converter shows better performance in minimizing torque ripple compared to the other topologies. The document concludes the modified Miller converter combined with closed-loop control can effectively reduce torque ripple in SRM for high-speed applications.
1. A document describes various types of losses that occur in DC generators and motors, including copper losses, iron losses, and mechanical losses.
2. Copper losses include armature and field winding losses, as well as brush contact resistance. Iron losses are due to hysteresis and eddy currents in the core.
3. Mechanical losses result from friction in bearings and windage. The Swinburne test is described as an indirect method to determine efficiency without separately measuring no-load losses.
A Novel Modified Turn-on Angle Control Scheme for Torque- Ripple Reduction in...IJPEDS-IAES
In recent years, Switched Reluctance Motors (SRM) have been dramatically
considered with both researchers and industries. SRMs not only have a
simple and reliable structure, but also have low cost production process.
However, discrete torque production of SRM along with intensive magnetic
saturation in stator and rotor cores are the major drawbacks of utilizing in
variety of industrial applications and also causes the inappropriate torque
ripples. In this paper, a modified logical-rule-based Torque Sharing Function
(TSF) method is proposed considering turn-on angle control. The optimized
turn-on angle for conducting each phase is achieved by estimating the
inductance curve in the vicinity of unaligned position and based on an
analytical solution for each phase voltage equation. Simulation results on a
four-phase switched reluctance motor and comparison with the conventional
methods validates the effectiveness of the proposed method.
This document describes the design and analysis of a modified fluid coupling for use in gearless two-wheel vehicles. The authors developed a computational model and experimental setup of a fluid coupling using Solidworks software. They then analyzed the setup using ANSYS to calculate stresses, strains, and efficiency. Based on the analysis, the authors determined that a fluid coupling with straight vanes provided better results than designs with 15 or 30 degree angled vanes. Testing of a prototype with straight vanes validated that it could withstand the required loads and stresses from the transmission fluid. The modified fluid coupling is intended to replace centrifugal clutches currently used in gearless scooters in order to reduce wear and provide smoother power transmission.
Fuel efficiency in construction equipment – optimize the machine as one systemReno Filla
In order to further optimize the fuel efficiency and productivity of construction equipment, 3 main potentials have been identified:
• job site optimization
• machine use optimization
• machine optimization
The focus of this paper is the machine optimization on the example of a wheel loader.
Optimizing losses in individual components must be done, but it will not be a game changer for fuel efficiency improvement. Three areas for promising improvement potentials:
• Optimizing the systems interactions
• Decoupling of systems
• Reduction of losses
One example is shown for a total machine optimization approach: the “Reverse by Braking” function is using the machine operating brakes to slow down the machine during power shuttle instead of using the engine power.
Decoupling of systems requires continuously variable transmission (CVT) functionality for the driveline. This can be achieved with hydraulic or electric CVTs. Two examples for decoupling systems are shown: the Volvo hydrostatic powersplit CVT prototype and a series hybrid wheel loader.
Further future potentials are explored, while the driveline and hydraulic technology are the enablers for drastic improvements: electrified site, plug in hybrid, alternative fuels, and new machine concepts.
1) The document discusses models for permanent magnet motor drives, specifically the permanent magnet synchronous motor (PMSM) and brushless DC motor (BDCM).
2) It explains that the PMSM has a sinusoidal back EMF and requires sinusoidal currents, while the BDCM has a trapezoidal back EMF and requires rectangular currents.
3) The paper argues that a d-q axis model is suitable for modeling the PMSM, while an ABC phase variable model should be used for the BDCM due to its non-sinusoidal inductances.
The document discusses vector control of permanent magnet synchronous motors (PMSM). It begins by describing the dynamic model of a PMSM, including assumptions made about the rotor flux. It then derives the stator equations in the rotor reference frame to model the PMSM similarly to an induction motor. Vector control of the PMSM is then derived from its dynamic model to decouple the torque and flux channels by controlling the stator currents in the d-q reference frame. This allows controlling the PMSM similarly to a separately excited DC motor.
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.
Mathematical Modelling of an 3 Phase Induction Motor Using MATLAB/Simulink IJMER
Mechanical energy is needed in the daily life use as well as in the industry. Induction motors
play a very important role in both worlds, because of low cost, reliable operation, robust operation and low
maintenance. To derive the mathematical model of a 3 phase Induction motor, the theory of reference
frames has been effectively used as an efficient approach. Dynamic models (mathematical models) are
employed in to better understand the behaviour of induction motor in both transient and steady state. The
dynamic modelling sets all the mechanical equations for the inertia, torque and speed versus time. It also
models all the differential voltage, currents and flux linkages between the stationary stator as well as the
moving rotor. This paper presents a step by step Matlab/Simulink implementation of an induction machine
using dq0 axis transformations of the stator and rotor variables in the arbitrary reference frame [1].
In recent years, Permanent Magnet Synchronous Machines (PMSMs) are increasing
applied in several areas such as generation, traction, automobiles, robotics and aerospace
technology. Basically PMSG topology has been beneficial for slow speed and variable speed
operation and steady state output power produced in operation. PMSG is a part of
synchronous machine family, so its construction features almost equivalent to synchronous
machine.
With respect of designing a PMSG, the permanent magnetic pole lies on the rotor and
armature winding are in the inner part of stator that is electrically connected to the load.
Armature winding consists of the set of three conductors which has phase difference 1200
apart to each other and providing a uniform force or torque on the generator’s rotor. To
operate PMGS, it is connected to wind turbine through a shaft without gear box and rotate at
slow speed. This uniform torque produced by the resultant magnetic flux which induces
current in the armature winding. The stator magnetic field combined spatially with rotor
magnetic flux and rotates as the same speed of the rotor. So the two magnetic fields
synchronously rotate in PGSM to maintain the relative motion of rotor and stator.
Thus the permanent magnets rotates at constant speed without any DC excitation system,
which means it has not required any slip rings and contact brushes to make it more reliability
or efficient.
This paper is intended to study and compare the operation of two methods for estimating the position/ speed of the permanent magnet synchronous motor (PMSM) under sliding mode control. The first method is a model reference adaptive system (MRAS). The second method based on sliding mode observer (SMO). The stability condition of Sliding Mode Observer was verified using the Lyapunov method to make sure that the observer is stable in converging to the sliding mode plane. In this paper the performances of the proposed two algorithms are analyzed using SIMULINK/MATLAB. The simulations results are presented to verify the proposed sensorless control algorithms and can resolve the problem of load disturbance effects by simulations which verify that the two closed-loop control system is robust with respect to torque disturbance rejection.
Design of a wind power generation system using a permanent magnet synchronous...eSAT Journals
Abstract This paper presents a wind power system using a Permanent Magnet Synchronous Machine (PMSM). The whole system consists of a wind turbine, a permanent magnet synchronous machine, a three phase diode rectifier, a boost converter, a transformer-less step down circuit, an H-bridge inverter and a T-LCL filter. The 3-phase AC output from the PMSM is sent to the 3-phase diode rectifier for conversion to DC and a boost regulator is used to step-up this DC voltage to the desired level. This step-upped DC voltage is then converted into AC output by the H-Bridge inverter. The switching technique of the proposed inverter consists of a combination of Sinusoidal Pulse Width Modulation (SPWM) and a square wave along with grid synchronization conditions. As the suggested method is entirely transformer-less, it significantly reduces Total Harmonic Distortion (THD) to less than 0.1% and minimizes its size. The T-LCL Immittance Converter not only reduces the harmonics of the inverter output but also provides a nearly constant output current thereby stabilizing the system. The system setup and the simulation results were obtained using the PSIM software. Keywords: Wind Turbine, Permanent Magnet Synchronous Machine, Boost Converter, Step- down Circuit, T-LCL Immittance Converter, Inverter
This ppt shows the modelling and simulation of permanent magnet synchronous motor by using torque control method.
And this is the most advanced and soffestigated method to control the pmsm motors.
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
Induction Motor Tests Using MATLAB/SimulinkGirish Gupta
This project describes MATLAB/Simulink implementation of three induction motor tests, namely DC, No-Load, and Blocked-Rotor tests which are performed to identify equivalent circuit parameters of an Induction Machine. These simulation models are developed to support and enhance electric machinery education at the undergraduate level.
Hardware implememtation of open end winding based multi levelsuvarnadasan
This document describes a project to implement an open-end winding based multilevel inverter. The project aims to drive a three-phase induction motor using two dual 2-level inverters. By opening the neutral point of the stator windings and feeding both sides with separate inverters, 3-level inversion is achieved. The basic circuit uses two 2-level inverters to generate pole voltages that result in stepped phase voltages to drive the motor. This provides improved power quality over conventional 2-level inverters.
This document summarizes research on techniques to minimize torque ripple in switched reluctance motors (SRM). It discusses that torque ripple is inherent in SRM due to their doubly salient structure. It reviews two main approaches: 1) Improving the magnetic design of the motor and 2) Using sophisticated electronic control techniques like indirect torque control methods using torque sharing functions or direct torque control. Indirect methods involve converting torque references to current references using look-up tables, while direct methods estimate torque directly from stored profiles. The document surveys literature on different torque sharing functions and controllers like hysteresis control and sliding mode control that can be used to optimize control parameters and minimize torque ripple.
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.
Torque Production & Control of Speed in Synchronous Motor.
Speed of synchronous motors can be controlled using two methods called open loop and close loop control.
Open loop contol is the simplest scalar control method where motor speed is controlled by independent frequency control of the converter.
In case of close loop self control mode, instead of controlling the inverter frequency independentaly, the frequency and the phase of the output waveform are controlled by an absolute position encoder mounted on the machine shaft giving an account of position of the rotor.
This document discusses direct current (DC) motors. It describes the construction and operating principles of different types of DC motors including series, shunt, compound and permanent magnet motors. It also discusses speed control methods for shunt and separately excited DC motors. The main methods of speed control are armature voltage control, field control and armature resistance control. Armature resistance control is simple but less efficient while field control provides better speed regulation.
This document discusses the theory and experimental procedures for determining the load characteristics of DC shunt, series, and compound motors. The experiments involve constructing circuits for each motor type and measuring speed, current, torque, power, and efficiency at increasing loads. Load characteristics such as speed regulation, starting torque, and efficiency are then determined and compared between motor types from the experimental results.
This document provides reading material on DC machines for electrical engineering students. It covers the basic principles of operation and torque equations for DC motors. It describes the operating characteristics such as speed-current, torque-current and speed-torque curves for shunt and series motors. It discusses starting methods such as 2-point, 3-point and 4-point starters. Methods of speed control including armature resistance, field flux and armature voltage control are explained. The document also covers losses, efficiency testing and applications of DC machines.
This document summarizes a paper that models and simulates a switched reluctance motor (SRM) to minimize torque ripple through different converter topologies and control strategies. The paper develops a mathematical model of a 6/4 SRM in Matlab/Simulink. It simulates the motor with asymmetric, Miller, and modified Miller converters. Torque ripple is evaluated using power spectrum density analysis. The modified Miller converter shows better performance in minimizing torque ripple compared to the other topologies. The document concludes the modified Miller converter combined with closed-loop control can effectively reduce torque ripple in SRM for high-speed applications.
1. A document describes various types of losses that occur in DC generators and motors, including copper losses, iron losses, and mechanical losses.
2. Copper losses include armature and field winding losses, as well as brush contact resistance. Iron losses are due to hysteresis and eddy currents in the core.
3. Mechanical losses result from friction in bearings and windage. The Swinburne test is described as an indirect method to determine efficiency without separately measuring no-load losses.
A Novel Modified Turn-on Angle Control Scheme for Torque- Ripple Reduction in...IJPEDS-IAES
In recent years, Switched Reluctance Motors (SRM) have been dramatically
considered with both researchers and industries. SRMs not only have a
simple and reliable structure, but also have low cost production process.
However, discrete torque production of SRM along with intensive magnetic
saturation in stator and rotor cores are the major drawbacks of utilizing in
variety of industrial applications and also causes the inappropriate torque
ripples. In this paper, a modified logical-rule-based Torque Sharing Function
(TSF) method is proposed considering turn-on angle control. The optimized
turn-on angle for conducting each phase is achieved by estimating the
inductance curve in the vicinity of unaligned position and based on an
analytical solution for each phase voltage equation. Simulation results on a
four-phase switched reluctance motor and comparison with the conventional
methods validates the effectiveness of the proposed method.
This document describes the design and analysis of a modified fluid coupling for use in gearless two-wheel vehicles. The authors developed a computational model and experimental setup of a fluid coupling using Solidworks software. They then analyzed the setup using ANSYS to calculate stresses, strains, and efficiency. Based on the analysis, the authors determined that a fluid coupling with straight vanes provided better results than designs with 15 or 30 degree angled vanes. Testing of a prototype with straight vanes validated that it could withstand the required loads and stresses from the transmission fluid. The modified fluid coupling is intended to replace centrifugal clutches currently used in gearless scooters in order to reduce wear and provide smoother power transmission.
Fuel efficiency in construction equipment – optimize the machine as one systemReno Filla
In order to further optimize the fuel efficiency and productivity of construction equipment, 3 main potentials have been identified:
• job site optimization
• machine use optimization
• machine optimization
The focus of this paper is the machine optimization on the example of a wheel loader.
Optimizing losses in individual components must be done, but it will not be a game changer for fuel efficiency improvement. Three areas for promising improvement potentials:
• Optimizing the systems interactions
• Decoupling of systems
• Reduction of losses
One example is shown for a total machine optimization approach: the “Reverse by Braking” function is using the machine operating brakes to slow down the machine during power shuttle instead of using the engine power.
Decoupling of systems requires continuously variable transmission (CVT) functionality for the driveline. This can be achieved with hydraulic or electric CVTs. Two examples for decoupling systems are shown: the Volvo hydrostatic powersplit CVT prototype and a series hybrid wheel loader.
Further future potentials are explored, while the driveline and hydraulic technology are the enablers for drastic improvements: electrified site, plug in hybrid, alternative fuels, and new machine concepts.
Enhanced Direct Torque Control for Doubly Fed InductionMachine by Active Lear...CSCJournals
The term Direct Torque Control (DTC) originally is referred to a strategy which provides good transient and steady-state performance but it has also some negative aspects, such as non accuracy of flux, torque estimator, torque and flux ripple caused by non-optimality of switching and imprecision in motor model which are known as an inherent characteristic of DTC. This paper explores reducing of flux and torque ripple with using trial and error actively as a method called Active Learning Method (ALM) in DTC for Doubly Fed Induction Machine (DFIM) which are the motors or generators having twist on both stator and rotor subsequence power is transferred between shaft and system. DFIM is linked to the grid within the stator and the rotor is fed by an Indirect Matrix Converter (IMC). The function of IMC is similar to the direct one, although it has the line and load bridges separated. We analysis the usage of four-step commutation in rectifier stage of IMC to achieve the object of the losses’ reduction which are caused by snubber circuit. ALM adopts itself with torque and flux estimators and estimates the outputs with regards to the errors in torque and flux estimation by repetition therefore achieves the object of omitting inaccuracies in control system hence confirming the effectiveness. Another concept in ALM called Ink Drop Spread (IDS) handles different modeling target to predict on the data consequensing a behavior curve in DTC. According to the simulation results, it is proved that a significant torque and stator flux ripple reduction are obtained.
IOSR Journal of Electrical and Electronics Engineering(IOSR-JEEE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of electrical and electronics engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electrical and electronics engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Informacion General del tren de fuerza del CAT 910Foliver Ramos
This document provides information about the power train of a Caterpillar 910 compact wheel loader, including descriptions of its main components and how they work together. It details the diesel engine, torque converter, transmission with four clutches for three forward speeds and one reverse, transfer gears, front and rear differentials, drive shafts, and final drives for the front and rear wheels. It also describes the transmission's lubrication system, including the hydraulic pump, oil cooler, and hydraulic controls that direct oil flow to engage the clutches.
This document provides an overview of automatic transmissions, including their key components:
1. Torque converters connect the engine to the gear train and multiply torque through fluid dynamics.
2. Planetary gear sets within the transmission allow for different gear ratios.
3. Hydraulic pressure from the transmission fluid causes gear shifts within the transmission.
The document then discusses specific components in more detail, including the torque converter's impeller, turbine, stator, and one-way clutch, as well as epicyclic gear trains and their application in automatic transmissions.
Using Dynamic Simulation in the Development of Construction MachineryReno Filla
As in the car industry for quite some time, dynamic simulation of complete vehicles is being practiced more and more in the development of off-road machinery. However, specific questions arise due not only to company structure and size, but especially to the type of product. Tightly coupled, non-linear subsystems of different domains make prediction and optimisation of the complete system's dynamic behaviour a challenge. Furthermore, the demand for versatile machines leads to sometimes contradictory target requirements and can turn the design process into a hunt for the least painful compromise. This can be avoided by profound system knowledge, assisted by simulation-driven product development. This paper gives an overview of joint research into this issue by Volvo Wheel Loaders and Linköping University on that matter, lists the results of a related literature review and introduces the term "operability". Rather than giving detailed answers, the problem space for ongoing and future research is examined and possible solutions are sketched.
http://arxiv.org/abs/cs/0305036
Optimal turn on and turn-off angles for torque ripple minimization of switche...eSAT Journals
Abstract Due to double saliency nature and non-linear magnetic characteristics the torque ripple is high in Switched Reluctance Motor. The torque ripple depends on the operating speed, current and turn off and turn-on angles of the converter. The performance of the motor is analyzed for Hysteresis Current Control with Fan type load with respect to torque ripple. The SRM with Hysteresis Current Control is analyzed for different combinations of turn-off and turn-on at a fixed reference speed to find out a pair of turn-on and turn-off angles at which torque ripple is minimum. Key Words: Switched Reluctance Motor, Torque Ripple, Hysteresis Current Control
The document describes an industrial tractor with an electromechanical transmission and switched reluctance electric machines. The electric drive and control system maintain the rated engine load, providing high efficiency and nearly perfect traction. The compliant suspension allows higher operating speeds and increased capacity. The tractor is designed for construction, mining, oil/gas, and other heavy industries. It can perform excavation in soils up to class IV, including frozen and collapsible rocky soils.
This document summarizes a study on implementing a 48V mild hybrid powertrain in a mid-size vehicle. The hybrid system would combine a downsized 1.2L turbocharged gasoline engine with an electric motor and electric supercharger. Simulation results showed this configuration could reduce fuel consumption and CO2 emissions by up to 10% compared to a baseline diesel vehicle, helping to meet the 2020 EU emission regulations. Key aspects of the study included benchmarking different vehicle types, selecting and optimizing the engine and hybrid components, developing an energy management strategy, and simulating performance on standard driving cycles as well as real-world routes.
Design of Switched Reluctance Motor for Three Wheeler Electric Vehicleidescitation
Switched Reluctance M achines (SRM ) offer
attractive attributes for automotive applications. Low cost, high
reliability, and competitive weight and efficiency combine to
make the switched reluctance (SR) motor drive a strong
candidate for application in future electric vehicle (EV)
propulsion systems. This paper proposes a methodology to
determine separately the peak and continuous power ratings
of a switched reluctance motor (SRM) for electric propulsion
of an electric vehicle (EV).same machine have to deliver peak
and continuous power for different road load condition of
vehicle. Then gives switched reluctance design guidelines for
battery operated electric vehicles. Finally, it presents the
design and simulation of a switched reluctance motor power
train.
Dinamo LLC is an engineering company that specializes in switched reluctance (SR) electric motor and drive systems. They design and manufacture SR motors, electronic control units, and integrate their systems into automation solutions. SR technology offers benefits like simple design, high efficiency, reliability, and cost competitiveness. Dinamo provides complete solutions from design to manufacturing to integration and maintenance.
A new low cost shrm for adjustable-speed pump applicationsSwathi Venugopal
This document presents a new low-cost switched reluctance motor (SHRM) for adjustable-speed pump applications. The motor uses inexpensive ferrite magnets arranged in a flux concentration configuration to increase torque density compared to conventional single-phase SR motors. Static and steady-state test results show that the prototype motor can produce the rated torque of 30W at 3000 rpm, though the measured torque is about 30% lower than expected, likely due to measurement errors. The efficiency of the overall drive system at rated speed is 70%, with major losses from iron loss in the motor can estimated at around 20W. Future work on noise reduction would be needed for indoor pump applications.
Synchonous machine design selection of no of slotsAjay Balar
The document discusses factors to consider when selecting the number of slots in an electric machine, including:
1. The number of slots affects cost and performance, with more slots providing advantages like reduced leakage reactance and better cooling but also disadvantages like increased cost and weaker teeth.
2. Key considerations for slot selection include slot loading being less than 1500A/slot, slot pitch limitations based on voltage, and selecting 3-4 or 7-9 slots per pole per phase for salient pole and turbo alternator machines.
3. Other factors discussed are tooth width, slot width, depth, and insulation to ensure proper space for conductors and prevent excessive flux density in teeth.
A torque converter is a fluid coupling used in automatic transmissions that transfers power from the engine to the transmission. It contains an impeller connected to the engine, a turbine connected to the transmission, and a stator in between. In different operating modes like stall and acceleration, the torque converter can multiply torque to help vehicles start moving or can act like a fluid coupling at higher speeds. Problems that can occur include overheating, stator clutch issues, blade damage, and housing distortion from extreme operating conditions.
Hybrid Power Systems for Construction Machinery: Aspects of System Design and...Reno Filla
This paper will examine the wheel loader as a system with two parallel energy conversion systems that show a complex interaction with each other and with the power source. Using a systematic design approach, several principle design solutions for hybridization can be found.
Furthermore, the human operator with his/her control actions needs to be considered as part of the total system. This paper will therefore also connect to results from ongoing and previous research into operator workload and operability.
http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-51999
http://dx.doi.org/10.1115/IMECE2009-10458
The document discusses different types of superchargers used in internal combustion engines. It explains that a supercharger is an air compressor that forces more air into the engine's intake manifold, allowing for more fuel to be burned and increasing engine power. Conventional superchargers are belt-driven but can consume up to 20% of engine power. Electrical superchargers address this issue by using a separate electric motor to compress air, providing boost without tapping the engine for power. The document outlines the components and advantages of an electrical supercharger system for a small gasoline engine.
The torque converter uses hydraulic principles to transmit power smoothly between a driving member and a driven member. It contains a pump, turbine, and adjustable guide vanes within a housing filled with hydraulic fluid. Mechanical energy from the motor is converted to hydraulic energy by the pump and back to mechanical energy by the turbine to drive the output shaft. Adjusting the guide vanes regulates the fluid flow and allows the torque converter to adapt the output speed and torque automatically based on the load.
INTRODUCTION
A chopper is a static device which is used to obtain a variable dc voltage from a
constant dc voltage source. A chopper is also known as dc-to-dc converter. The thyristor converter offers greater efficiency, faster response, lower maintenance, smaller size and smooth control. Choppers are widely used in trolley cars, battery operated vehicles, traction motor control, control of large number of dc motors, etc….. They are also used in regenerative braking of dc motors to return energy back to supply and also as dc voltage regulators.
Choppers are of two types
• Step-down choppers
• Step-up choppers.
In step-down choppers, the output voltage will be less than the input voltage
whereas in step-up choppers output voltage will be more than the input voltage.
Classification of Choppers:
(a) Depending upon the direction of the output current and voltage, the converters can be classified into five classes namely Class A [One-quadrant Operation] Class B [One-quadrant Operation] Class C [Two-quadrant Operation] Class D [Two-quadrant Operation] Class E [Four-quadrant Operation]
(b) Based on the output voltage of the output, the choppers are classified as
(i) Step-Down Chopper In this case the average output voltage is less than the input voltage. It is also known as step down converter
(ii) Step-Up Chopper Here the average output voltage is more than the input voltage. It is also known as step up converter
(iii) Step-Up/Down Chopper This type of converter produces an output voltage that is either lower or higher than the input voltage
(c) Depending upon the power loss occurred during turn ON/OFF of the switching device, the choppers are classified into two categories namely
(i) Hard switched Converter Here the power loss is high during the switching (ON to OFF and OFF to ON) as a result of the non zero voltage and current on the power switches.
(ii) Soft switched or resonant converters In this type of choppers, the power loss is low at the time of switching as a result of zero voltage and/or zero current on the switches.
2
PRINCIPLE OF STEP-DOWN CHOPPER
Figure 2.1 shows a step-down chopper with resistive load. The thyristor in the
circuit acts as a switch. When thyristor is ON, supply voltage appears across the load and
when thyristor is OFF, the voltage across the load will be zero. The output voltage and
current waveforms are as shown in figure 2.2.
The document discusses switched reluctance motors (SRMs). It provides information on the working principle, elementary operation, inductance profiles, configurations, selection of phases, converter configurations, control, sensorless operation, and applications of SRMs. Key points include that SRMs operate based on variable reluctance torque, power is transmitted through stator windings rather than the rotor, and proper control of current timing and magnitude can produce smooth torque from discrete pulses. SRMs are applicable where size and power-to-weight ratio are critical factors.
Iaetsd a decisive fuzzy controlled single switch basedIaetsd Iaetsd
This document describes a proposed fuzzy logic controller for a switched reluctance motor (SRM) drive system. It presents a new single-switch converter topology for SRM drives that aims to improve performance with a simple design. Simulation results using Matlab/Simulink show that the proposed converter fed SRM drive has faster response and settling times under closed-loop control compared to open-loop operation, and further improvement when using a fuzzy logic controller. The fuzzy logic controller design and simulation results validating its ability to enhance the dynamic performance of the SRM drive are discussed.
Closed Loop Speed Control of a BLDC Motor Drive Using Adaptive Fuzzy Tuned PI...IJERA Editor
Brushless DC Motors are widely used for many industrial applications because of their high efficiency, high
torque and low volume. This paper proposed an improved Adaptive Fuzzy PI controller to control the speed of
BLDC motor. This paper provides an overview of different tuning methods of PID Controller applied to control
the speed of the transfer function model of the BLDC motor drive and then to the mathematical model of the
BLDC motor drive. It is difficult to tune the parameters and get satisfied control characteristics by using normal
conventional PI controller. The experimental results verify that Adaptive Fuzzy PI controller has better control
performance than the conventional PI controller. The modeling, control and simulation of the BLDC motor have
been done using the MATLAB/SIMULINK software. Also, the dynamic characteristics of the BLDC motor (i.e.
speed and torque) as well as currents and voltages of the inverter components are observed by using the
developed model.
This document discusses vector control of an 8/6 switched reluctance motor (SRM) using a fuzzy logic controller (FLC). It begins with an introduction to SRM and discusses its construction, operating principle, and mathematical model. It then describes the use of direct torque control (DTC) to regulate the motor's torque output within a hysteresis band by controlling stator flux linkage and speed. The document outlines the development of an FLC for SRM speed control, including defining membership functions and fuzzy rules. Simulation results show waveforms for motor torque, speed, and current outputs indicating speed regulation and low torque ripple. The summary concludes the FLC provides accurate SRM control with fast torque/flux response and lower sampling time
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Fuzzy logic Control & Minimizing Commutation Torque Ripple for Brushless DC M...Editor IJMTER
Brushless dc motor still suffers from commutation torque ripple, which mainly depends
on speed and transient line current in the commutation interval. This paper presents a novel circuit
topology and a dc link voltage control strategy to keep incoming and outgoing phase currents
changing at the same rate during commutation. A dc–dc single-ended primary inductor converter
(SEPIC) and a switch selection circuit are employed in front of the inverter. The desired
commutation voltage is accomplished by the SEPIC converter. The dc link voltage control strategy is
carried out by the switch selection circuit to separate two procedures, adjusting the SEPIC converter
and regulating speed. The cause of commutation ripple is analyzed, and the way to obtain the desired
dc link voltage is introduced in detail. Finally, simulation and experimental results show that,
compared with the dc–dc converter, the proposed method can obtain the desired voltage much faster
and minimize commutation torque ripple more efficiently at both high and low speeds and the closed
loop control is achieved by Fuzzy logic control.
Numerous studies had been made to improve the switched reluctance motor operation depend on the modification of the machine design, proposing the converter designs and/or applying a suitable control method. This paper introduces the field orientation control method for that motor using a simple and very efficient DC-DC converter topology. This control method is presented by two techniques; first technique is the advance of the turn-on switching angle and the other technique is the retard/delay of the turn-off switching angle. Instantaneous and average motor characteristics are obtained using Matlab/Simulink software package. Comparison between the simulation results presented using two converter types. A precise speed and torque control are obtained. The average total torque per current is maximized.
This document summarizes a research paper that proposes a new switched capacitance power converter for a 6/4 switched reluctance motor drive. The proposed converter aims to reduce torque ripple and allow constant speed to be achieved more quickly with reduced power loss compared to an asymmetric converter. The operating principles and design of the proposed converter are described. Simulation results using MATLAB Simulink show that the proposed converter produces less torque oscillation and maintains a constant speed of 4500 RPM, making it suitable for low and medium speed applications.
1) A servo is a feedback control system that controls the position or motion of a mechanical system. It receives an input signal and uses feedback to control velocity and position.
2) An electrical servo system relies on electrical energy and feedback to provide fast, accurate, and remote control. It has an error detector, amplifier, and error corrector to match the controlled variable to a reference signal.
3) A DC servo motor uses separate power sources for the field and armature windings. It can be field controlled, where the field is controlled by feedback, or armature controlled, where the armature is controlled by feedback. Field control provides slower response while armature control provides faster response.
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.
This document discusses traction motors used in electric rail vehicles. It covers the requirements of traction systems including high starting torque and withstanding overloads. DC series motors are well suited due to developing high torque at low speeds. Speed can be controlled through methods like armature voltage and current control. Modern control uses pulse width modulation and regenerative braking returns energy to the supply system. Recent trends include use of multilevel converters for smooth waveforms and reduced harmonic losses.
The Journal of MC Square Scientific Research is published by MC Square Publication on the monthly basis. It aims to publish original research papers devoted to wide areas in various disciplines of science and engineering and their applications in industry. This journal is basically devoted to interdisciplinary research in Science, Engineering and Technology, which can improve the technology being used in industry. The real-life problems involve multi-disciplinary knowledge, and thus strong inter-disciplinary approach is the need of the research.
This document presents information about induction motor control methods. It introduces scalar and vector control of induction motors. Scalar control varies only the magnitude of control variables, while vector control accounts for coupling effects. Scalar control is simpler to implement but provides poorer dynamic response than vector control. Vector control allows for precise control of AC motors and excellent dynamic response, but requires a more complex mathematical model. The document also compares the advantages and disadvantages of each control method.
This document provides an overview of electric motors, including different types of motors, their basic principles and components. It discusses induction motors, synchronous motors, and single phase motors. It also covers motor specifications, testing, storage, lubrication, and maintenance practices. The presentation was prepared by Kapil Singh for Thermax Ltd and includes topics like classification of motors, laws of electromagnetism, rotating magnetic fields, and motor applications.
DC machines can achieve wide range speed control through three main methods - armature resistance control to vary speed below base speed, field flux control to vary speed above base speed, and armature voltage control using systems like Ward-Leonard which combine armature and field control to achieve the widest speed range from below to above base speed. Controlled rectifiers and series-parallel configurations are also used to vary armature voltage for smooth speed regulation.
This document presents a new method for starting induction motors to improve transient torque pulsations. It develops a mathematical model of a 415V, 4.7A, 1435rpm induction motor in MATLAB/Simulink. The proposed method connects two phases (Y and B) at startup, with the third phase (R) delayed by 0.0133333 seconds. Simulations show this unbalanced startup reduces torque pulsations and starting current compared to normal startup. The method provides smooth motor acceleration and high starting torque with minimized transients, making it suitable for induction motor applications.
Report On diode clamp three level inverterVinay Singh
three level diode clamp inverter. that converts any type of DC ( rectified, PV cell, battery etc.) to AC supply. we made by mosfet and ardiuno . in this ppt we present the Simulink model of a three-level inverter and the hardware reort of the inverter.
also discuss about other level inverter and there THD analysis, simulink model and detail. compression between another inverter.
This paper presents a novel converter configuration with fewer for switched reluctance motor (SRM) drive. The proposed novel converter insists for less number of switches compared to conventional asymmetrical type of converter configuration for switched reluctance motor. Switch count reduction in converter reduces the losses, volume of heat sink, and number of gate drive circuits and thereby the performance of the system. Closed loop speed control of switched reluctance motor fed from proposed novel converter topology was presented in this paper. Performance of closed loop operation is compared to open loop system. Further the proposed converter for SRMT is evaluated with loaded condition and comparative analysis of no-load and loaded SRM is presented. The model presented is developed and the results are analyzed using MATLAB/SIMULINK software. Closed loop performance of proposed novel converter fed switched reluctance motor drive is verified at fixed speed and variable speed conditions.
This document discusses traction motors used in electric rail vehicles. It covers the requirements of traction systems including high starting torque and withstanding overloads. Common types of traction motors are described like DC series motors and induction motors. Methods of controlling DC motor speed are explained, particularly electronic speed control using pulse width modulation. Braking methods for traction motors include dynamic braking by converting motors to generators and regenerative braking by feeding energy back to the supply system. Recent trends involve using multilevel converters for improved waveforms and reduced harmonics.
Similar to Performance Analysis of Current Controlled Three Phase Switched Reluctance Motor (20)
This document summarizes a research paper that proposes using an artificial neural network tuned by a simulated annealing algorithm for real-time credit card fraud detection. The paper describes how simulated annealing can be used to train the weights of a neural network model to classify credit card transactions as fraudulent or non-fraudulent based on attributes of past transactions. The algorithm is tested on a real-world credit card transaction dataset and is found to effectively classify most transactions correctly, though some misclassifications still occur.
Wireless sensor networks (WSN) have been widely used in various applications.
In these networks nodes collect data from the attached sensors and send their data to a base
station. However, nodes in WSN have limited power supply in form of battery so the nodes
are expected to minimize energy consumption in order to maximize the lifetime of WSN. A
number of techniques have been proposed in the literature to reduce the energy
consumption significantly. In this paper, we propose a new clustering based technique
which is a modification of the popular LEACH algorithm. In this technique, first cluster
heads are elected using the improved LEACH algorithm as usual, and then a cluster of
nodes is formed based on the distance between node and cluster head. Finally, data from
node is transferred to cluster head. Cluster heads forward data, after applying aggregation,
to the cluster head that is closer to it than sink in forward direction or directly to the sink.
This reduction in distance travelled improves the performance over LEACH algorithm
significantly.
This document provides an overview of vertical handover decision strategies in heterogeneous wireless networks. It begins with an introduction to always best connectivity requirements in next generation networks that allow users to move between different network technologies. It then discusses the key aspects of handover management, including the three phases of initiation, decision, and execution. Various criteria for the handover decision process are described, such as received signal strength, network connection time, available bandwidth, power consumption, cost, security, and user preferences. Different types of handover decision strategies are categorized, including those based on network conditions, user preferences, multiple attributes, fuzzy logic/neural networks, and context awareness. The strategies are analyzed and their advantages/disadvantages compared.
This paper presents the design and performance comparison of a two stage
operational amplifier topology using CMOS and BiCMOS technology. This conventional op
amp circuit was designed by using RF model of BSIM3V3 in 0.6 μm CMOS technology and
0.35 μm BiCMOS technology. Both the op amp circuits were designed and simulated,
analyzed and performance parameters are compared. The performance parameters such as
gain, phase margin, CMRR, PSRR, power consumption etc achieved are compared. Finally,
we conclude the suitability of CMOS technology over BiCMOS technology for low power
RF design.
In Cognitive Radio Networks (CRN), Cooperative Spectrum Sensing (CSS) is
used to improve performance of spectrum sensing techniques used for detection of licensed
(Primary) user’s signal. In CSS, the spectrum sensing information from multiple unlicensed
(Secondary) users are combined to take final decision about presence of primary signal. The
mixing techniques used to generate final decision about presence of PU’s signal are also
called as Fusion techniques / rules. The fusion techniques are further classified as data
fusion and decision fusion techniques. In data fusion technique all the secondary users
(SUs) share their raw information of spectrum detection like detected energy or other
statistical information, while in decision fusion technique all the SUs take their local
decisions and share the decision by sending ‘0’ or ‘1’ corresponding to absence and presence
of PU’s signal respectively. The rules used in decision fusion techniques are OR rule, AND
rule and K-out-of-N rule. The CSS is further classified as distributed CSS and centralized
CSS. In distributed CSS all the SUs share the spectrum detection information with each
other and by mixing the shared information; all the SUs take final decision individually. In
centralized CSS all the SUs send their detected information to a secondary base station /
central unit which combines the shared information and takes final decision. The secondary
base station shares the final decision with all the SUs in the CRN. This paper covers
overview of information fusion methods used for CSS and analysis of decision fusion rules
with simulation results.
This paper analyzes the impact of network scalability on various physical attributes of Zigbee networks. Simulations were conducted using Qualnet to evaluate the performance of the Zigbee physical layer based on energy consumption and throughput. Energy consumption was analyzed for different modulation schemes (ASK, BPSK, OQPSK), network sizes (2-50 nodes), and clear channel assessment modes. The results showed that OQPSK and ASK had lower energy consumption than BPSK. Throughput was highest for OQPSK. While carrier sense had slightly higher throughput than other CCA modes, the energy consumption differences between CCA modes were minor.
This paper gives a brief idea of the moving objects tracking and its application.
In sport it is challenging to track and detect motion of players in video frames. Task
represents optical flow analysis to do motion detection and particle filter to track players
and taking consideration of regions with movement of players in sports video. Optical flow
vector calculation gives motion of players in video frame. This paper presents improved
Luacs Kanade algorithm explained for optical flow computation for large displacement and
more accuracy in motion estimation.
A rapid progress is seen in the field of robotics both in educational and industrial
automation sectors. The Robotics education in particular is gaining technological advances
and providing more learning opportunities. In automotive sector, there is a necessity and
demand to automate daily human activities by robot. With such an advancement and
demand for robotics, the realization of a popular computer game will help students to learn
and acquire skills in the field of robotics. The computer game such as Pacman offers
challenges on both software and hardware fronts. In software, it provides challenges in
developing algorithms for a robot to escape from the pool of attacking robots and to develop
algorithms for multiple ghost robots to attack the Pacman. On the hardware front, it
provides a challenge to integrate various systems to realize the game. This project aims to
demonstrate the pacman game in real world as well as in simulation. For simulation
purpose Player/Stage is used to develop single-client and multi-client architectures. The
multi- client architecture in player/stage uses one global simulation proxy to which all the
robot models are connected. This reduces the overhead to manage multiple robots proxy.
The single-client architecture enables only two robot models to connect to the simulation
proxy. Multi-client approach offers flexibility to add sensors to each port which will be used
distinctly by the client attached to the respective robot. The robots are named as Pacman
and Ghosts, which try to escape and attack respectively. Use of Network Camera has been
done to detect the global positions of the robots and data is shared through inter-process
communication.
In Content-Based Image Retrieval (CBIR) systems, the visual contents of the
images in the database are took out and represented by multi-dimensional characteristic
vectors. A well known CBIR system that retrieves images by unsupervised method known
as cluster based image retrieval system. For enhancing the performance and retrieval rate
of CBIR system, we fuse the visual contents of an image. Recently, we developed two
cluster-based CBIR systems by fusing the scores of two visual contents of an image. In this
paper, we analyzed the performance of the two recommended CBIR systems at different
levels of precision using images of varying sizes and resolutions. We also compared the
performance of the recommended systems with that of the other two existing CBIR systems
namely UFM and CLUE. Experimentally, we find that the recommended systems
outperform the other two existing systems and one recommended system also comparatively
performed better in every resolution of image.
Information Systems and Networks are subjected to electronic attacks. When
network attacks hit, organizations are thrown into crisis mode. From the IT department to
call centers, to the board room and beyond, all are fraught with danger until the situation is
under control. Traditional methods which are used to overcome these threats (e.g. firewall,
antivirus software, password protection etc.) do not provide complete security to the system.
This encourages the researchers to develop an Intrusion Detection System which is capable
of detecting and responding to such events. This review paper presents a comprehensive
study of Genetic Algorithm (GA) based Intrusion Detection System (IDS). It provides a
brief overview of rule-based IDS, elaborates the implementation issues of Genetic Algorithm
and also presents a comparative analysis of existing studies.
Step by step operations by which we make a group of objects in which attributes
of all the objects are nearly similar, known as clustering. So, a cluster is a collection of
objects that acquire nearly same attribute values. The property of an object in a cluster is
similar to other objects in same cluster but different with objects of other clusters.
Clustering is used in wide range of applications like pattern recognition, image processing,
data analysis, machine learning etc. Nowadays, more attention has been put on categorical
data rather than numerical data. Where, the range of numerical attributes organizes in a
class like small, medium, high, and so on. There is wide range of algorithm that used to
make clusters of given categorical data. Our approach is to enhance the working on well-
known clustering algorithm k-modes to improve accuracy of algorithm. We proposed a new
approach named “High Accuracy Clustering Algorithm for Categorical datasets”.
Brain tumor is a malformed growth of cells within brain which may be
cancerous or non-cancerous. The term ‘malformed’ indicates the existence of tumor. The
tumor may be benign or malignant and it needs medical support for further classification.
Brain tumor must be detected, diagnosed and evaluated in earliest stage. The medical
problems become grave if tumor is detected at the later stage. Out of various technologies
available for diagnosis of brain tumor, MRI is the preferred technology which enables the
diagnosis and evaluation of brain tumor. The current work presents various clustering
techniques that are employed to detect brain tumor. The classification involves classification
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2. In this paper hysteresis current control is applied to proposed converter for switched reluctance motor and
simulation result is obtained at no l oa d and load condition by MATLAB/SIMULINK.[5-7]
II. SRM PRINCIPLE OF OPERAT IO N
SRM differ in the number of phases wound on the stator. Each of them has a certain number of suitable
combinations of stator and rotor poles. Fig.1 illustrates a typical 3-phase SRM with a six stator /four rotor
pole configuration. The rotor of an SRM is said to be at the aligned position with respect to a fixed phase if
the current reluctance has the minimum value and the rotor is said to be in the unaligned position with
respect to a fixed phase if the current reluctance reaches its maximum value.
The motor is excited by a sequence of current pulses applied at each phase. The individual phases are
consequently excited, forcing the motor to rotate. The current pulses must be applied to the respective
phase at the exact rotor position relative to the excited phase. When any pair of rotor poles is exactly in line
with the stator poles of the selected phase, the phase is said to be in an aligned position; i.e., the rotor in the
position of maximum stator inductance.
Figure. 1 Three phase 6/4 SRM
The inductance profile of SRM is triangular, with maximum inductance when it is in an aligned position and
minimum inductance when unaligned.
III. CHARACTERISTICS OF SRM CONVE RT ER
One of the key topics for research in Switched Reluctance Motor drives is the converter topology design.
The performance of the Switched Reluctance Motor drive is highly affected by the performance and
characteristic of converters. Conventional SRM converters are commercially available, and phase
independence and unipolar current are applied widely in industrial applications.[23].Several varieties of
converter topologies have been presented in the last 30 years [10]-[12].With continued research, different
topologies have emerged presenting reduced numbers of power switches, faster excitation time, faster
demagnetization time, high efficiency, high power factor, and high power [24]-[26].In accordance with
the operational characteristic of the Switched Reluctance motor, the converter has some basic
requirements:
1.Each phase of the Switched Reluctance motor should be able to conduct independently. It means that one
phase has at least one switch for motor operation.
2.The converter should be able to demagnetize the phase before it steps into the regenerating region. If the
machine is operating as a motor, it should be able to excite the phase before it enters the generating region.
To improve the performance, the converter must satisfy the following additional requirements: (1) allow
phase overlap control; (2) utilize the demagnetization energy from the outgoing phase in a useful way either
by feeding it back to the source (DC- link capacitor) or by using it in the incoming phase; (3) generate
sufficiently high negative voltage for the outgoing phase given a short commutation period in order to
reduce demagnetization time;(4) use the freewheel during the chopping period to reduce switching
frequency; (5) support high positive excitation voltage for building up a higher phase current, which
may improve the output power of motor; (6) acquire resonant circuit in order to apply zero- voltage or zerocurrent switching, and to reduce switching loss; and(7) apply power factor correction circuit in order to
improve the power factor.
137
3. IV. INDUCTANCE PROFILE OF S RM
For a constant phase voltage, the phase current has its maximum value in the position when the inductance
begins to increase. This corresponds to the position where the rotor and the stator poles start to overlap.
When a phase is turned off, the current flowing in that phase r e d u c e s to zero. The phase current present in
the region of decreasing inductance generates negative torque. The torque generated by the motor is
controlled by the applied phase voltage and the appropriate definition of turn-on and turn-off angles. As is
apparent from the description, the SRM requires position feedback for motor phase commutation. In many
cases, this requirement is addressed by using position sensors, such as encoders or Hall sensors. The result
is that the implementation of mechanical sensors increases costs and decreases system reliability.
When current flows in a phase, the resulting torque tends to move the rotor in a direction that leads to an
increase in the inductance. Provided that there is no residual magnetization of steel, the direction of current
flow is immaterial and the torque always tries to move the rotor to the position of highest inductance.
Positive torque is produced when the phase is switched on while the rotor is moving from the unaligned
position to the aligned position.
V. MATHEMATICAL M ODEL OF S RM
The phase voltage of the switched reluctance motor can be written as
=
+
---(1)
Where, V is the bus voltage, ‘i’ is the instantaneous phase current ,R is the phase winding resistance and
flux linkage in the coil. Ignoring stator resistance, the above equation can be written as
=
+
---(2)
Where,
is the rotor speed and L( is the instantaneous phase resistance.
The power equation can also be written in the form of
( )
= ( ) +
---(3)
Where, the first term of the above equation represents the rate of increase in the stored magnetic field
energy while the second term is the mechanical output. Thus, the instantaneous torque can be written as
( , )=
-----(4)
Thus positive torque is produced when the phase is switched on during the rising inductance. Consequently,
if the phase is switched on during the period of falling inductance, negative torque will be produced.
VI. PROPOSED CON VERTER
The proposed converter consists of two discrete switching devices and two freewheeling diodes per phase,
as shown in Fig .2.Each phase of converter is the dependent of others, so independent current control can be
applied.
The proposed converter has three possible modes of operation. Take one phase into consideration, when
both switching device are turned-on, positive magnetizing voltage is applied, and current rises rapidly in the
phase winding. If under low-speed operation, phase current will exceed its demanded value fast. At this
time, one switch turns off and current circulates through the other switch and one diode. There is no energy
transfer between phase winding and dc source. This operation is the so-called freewheeling mode, which
applies a low demagnetizing voltage to the phase winding. When both switching device turned off,
winding current circulates through two diodes and recharge the capacitor. The demagnetization process is
much quicker than freewheeling mode.
The operating modes of an asymmetric converter are shown in Fig. 2.As an independent phase control, the
asymmetric converter has three modes. These modes are defined as magnetization, freewheeling, and
demagnetization, as shown in Fig. 2(a)–(c), respectively.
Mode1:Magnetizing stage
In this mode,both switches T1and T2 in a phase leg are on,and phase is energized from the supply voltage.
The current flow path is Vdc+ -T1-Winding- T2-Vdc -.
138
4. Figure .2 proposed three-phase asymmetric converter
Figure.2.a Magnetization Mode
Mode2:Freewheeling stage
When both switches are off, the freewheeling diodesD1 and D2 allow the exciting current in the coil to keep
flowing in the same direction .However the reverse voltage is applied to the excitation coil forces the current
to decrease.The current flow path is A2-D1-Vdc+ -Vdc- -D2-A1.
Figure2.b Freewheeling Mode
Mode3: Demagnetizing stage
When any one switch is turned on, the stored energy is dissipated by the phase resistance and the back emf
developed in the coil,and thus, the phase current slowly decreases. If the initial current is zero, then the
current will remain zero, because there is no voltage applied across the coil.The switches are turned on T2
and turned off T1 to control the desired current level for each phase.
139
5. Figure 2.c Demagnetization Mode
V. HYSTERESIS C URRENT CONTROL
Hysteresis current controller maintains a more or less constant current throughout the conduction period in
each phase. From Fig.3, the rotor position sensor is connected from the rotor and then the output signal from
the rotor position sensor is given as feedback at the base of the transistor T2.From the emitter of T2,
the portion of feedback current signal is fed at the input of operational amplifier. The operational
amplifier compares reference current signal and phase current.The output signal of the operational amplifier
is fed to the base signal of transistor T1.This signal in combination with collector current will flow from the
emitter of transistor T1 through phase winding of the motor. The current flow through the phase winding is
controlled by turning on and turn off of transistor T1 and T2. The rotor position sensor of switched
reluctance motor is simulated and shown in Fig .5.
Figure .3 Hysteresis current control
VI. SIMULATION RESULTS & DISCUSSION
In this simulink, a DC supply voltage of 240 V is used. The converter turn-on and turn-off angles are
kept constant at 45 deg and 75 deg, respectively, over the speed range. The reference current is 100 A
and the hysteresis band is chosen as +-10 A. The SRM is started by applying the step reference to the
regulator input. The acceleration rate depends on the load characteristics. To shorten the starting time, a
very light load was chosen. Since only the currents are controlled, the motor speed will increase
according to the mechanical dynamics of the system. The SRM drive waveforms (phase voltages,
magnetic flux, windings currents, motor torque, motor speed) are displayed on the scope. As can be
noted, the SRM torque has a very high torque ripple component which is due to the transitions of the
currents from one phase to the following one. This torque ripple is a particular characteristic of t he SRM
and it depends mainly on the converter s turn-on and turn-off angles. In observing the drive's waveforms,
we can remark that the SRM operation speed range can be divided into two regions according to the
converter operating mode: current-controlled and voltage-fed.
140
6. A. Current-controlled mode
From stand still up to about 3000 rpm, the motor's emf is low and the current can be regulated to the
reference value. In this operation mode, the average value of the developed torque is approximately
proportional to the current reference. In addition to the torque ripple due to phase transitions, we note
also the torque ripple created by the switching of the hysteresis regulator.This operation mode is also
called constant torque operation.
B. Voltage-fed mode
For speeds above 3000 rpm, the motor's emf is high and the phase currents cannot attain the refere nce
value imposed by the current regulators.The converter operation changes naturally to voltage-fed mode in
which there is no modulation of the power switches. They remain closed during their active periods a nd
the constant DC supply voltage is continuously applied to the phase windings. This results in linear
varying flux waveforms as shown on the scope. In voltage-fed mode, the SRM develops its 'natural'
characteristic in which the average value of the developed torque is inversely proportional to the motor
speed. Since the hysteresis regulator is inactive in this case, only torque ripple due to phase transition.
The proposed converter is simulated by
MATLAB/SIMULINK and shown in Fig.4.Torque, current ,
phase voltage ,speed and flux linkage curves of SRM is obtained at load and no load condition. From
the Fig.8 the phase voltage has more spikes at no load condition. When the load increased the voltage spikes
has reduced in Fig.12.Fig.9 and Fig.13.shows the current though the phase winding around 100A and it
has less distortion. At no load condition, the torque developed by the motor is positive in Fig.10.When the
load is applied the negative torque is produced due to back emf in Fig.14.The flux linkage waveform is
obtained at different rotor position is shown in Fig.6 . Fig.7 and Fig.15 shows the flux linkage waveform
at load and no-load condition. The speed response of switched reluctance motor is obtained around 2700
RPM in Fig .11.
Figure 4. Simulink model of asymmetric bridge converter for 3 phase 6/4 SRM
141
7. Figure .5 Rotor position Sensor
Figure .6 Flux linkage vs. current at different rotor position
Figure. 7 Flux linkage Vs Time wave form at No load
142
8. Figure.8 Voltage waveform of phase winding at No load
Figure. 9 Current waveform of phase winding at No load
Figure.10 Torque wave form of switched reluctance motor at No load
143
9. Figure.11 Speed wave form of switched reluctance motor
Figure. 12 Voltage waveform of phase winding at load torque 5Nm
Figure.13 current waveform of phase winding at load torque 5Nm
144
10. Figure.14 Torque wave form of switched reluctance motor at load torque 5Nm
Figure. 15 Flux linkage wave form at load torque 5Nm
VII. CONCLUSION
In this paper, the performance of switched reluctance motor is obtained at no load and load condition by
proposed converter. From the simulation it is being observed that the torque is developed during
change of inductance. For constant inductance (un aligned position) torque developed is zero. To get
positive torque, voltage should apply during rising inductance whereas negative torque will develop
during falling inductance. The torque pulsation in switched reluctance motor can be minimized by
intelligent control like fuzzy, neuro fuzzy, and PSO.
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