EPE Association: EPE-PEMC 2004 - Topic 05-1: Permanent magnet machines and drives

EPE-PEMC 2004 - Topic 05-1: Permanent magnet machines and drives
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2004 - Conference > EPE-PEMC 2004 - Topic 05: ELECTRICAL MACHINES AND ACTUATORS > EPE-PEMC 2004 - Topic 05-1: Permanent magnet machines and drives

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   A Simple Initial Position Detecting Method For PMSMS By Means Of AC Excitation
By Kazuhiko Ono, Hironori Hirato, Shoji Nishikata [View]
[Download]

Abstract: A new and simple detecting method of initial rotor position for permanent magnet synchronous motors without any position sensors is proposed. The intended method is based on observing the emf waveforms induced in the armature windings when a single-phase AC source is applied to one of the windings. ° The observation includes the comparison of the amplitudes and slopes of the emf waveforms in order to detect the rotor position. According to this method, initial rotor position can be detected every 30°. Finally, it is shown that the tested motor started successfully with the proposed position detecting method, confirming the usefulness of the method.

   Analytical Calculation Of Magnetic Field Distribution In The Slotted Air Gap Of A Surface PM Motor Using Complex Relative Air Gap Permeance
By Damir Zarko, Thomas A. Lipo, Drago Ban [View]
[Download]

Abstract: An analytical method for calculation of no-load magnetic field distribution in the slotted air gap of a surface PM motor with radial or parallel magnetization is presented. The method introduces the notion of complex relative air gap permeance calculated from the conformal transformation of the slot geometry to take into account the effect of slotting. As a result an accurate solution of both radial and tangential components of the flux density can be obtained which shows excellent agreement with the results of finite element simulations. The effectiveness of the model has been shown on an example of a surface PM motor for which the back emf and the cogging torque waveforms have been calculated.

   Design Of A Novel Permanent Magnet Linear Actuator For Short-Stroke And High-Dynamic Motions
By Steffen Braune, Steven Liu [View]
[Download]

Abstract: In this paper the design procedure of a novel permanent-magnet linear actuator is described. The main focusing point is to choose a proper geometry of the actuator components in order to meet the special specifications required by the intended application (very high dynamic, short-stroke, small volume and low power dissipation). Combined analytical and finite-element calculations are used to optimise the actuator performance. Calculation and simulation curves demonstrate the design results.

   Determination Of Resistive Parameters And Iron Losses In Vector Controlled PM Synchronous Motors With Rotor Saliency
By M. Tursini, R. Petrella, T. Daloisio [View]
[Download]

Abstract: This paper presents a new approach to estimate the resistive parameters of the equivalent circuit in inverter-fed vector-controlled salient rotor permanent magnet synchronous motors. The method is based on the particular two-values shape of the loss power-vs.-current characteristic, when the motor is operated at constant output torque, constant speed and variable direct (d) current component. Such a profile allows to process the standard current/power/voltage measurements with a differential criteria, in order to minimize and theoretically cancel out the effects of non easily quantifiable phenomena, such as temperature, fundamental frequency, inverter feeding and additional losses. The presented method allows the contemporary estimation of the stator resistance and the iron losses equivalent resistor. A particular feature is that the resistive parameters are achieved in the practical operating conditions in the constant torque region. In fact they are identified near the minimum of the loss power-vs.-current characteristics, which is close to the maximum torque-to-current trajectory in the d-q currents plane. The paper covers the illustration of the basic elements of the method, some issues on the implementation problems, and the experimental results achieved on a motor-drive system for city-scooter application, which confirm the goodness of the proposal.

   Fault Interrupting Methods And Topologies For Interior PM Machine Drives
By Brian A. Welchko, Thomas M. Jahns, Thomas A. Lipo [View]
[Download]

Abstract: This paper investigates methods to interrupt the phase currents induced when interior PM (IPM) motor drives suffer short-circuit or uncontrolled generator mode faults. A fault-tolerant silicon switch is proposed in which the antiparallel diode in a reverse-blocking IGBT is replaced in by an SCR. A reduced parts count fault interrupting topology is also proposed which consists of delta-connected thyristors inserted into the center of a wye-connected IPM motor stator. Control of the proposed reduced parts count fault-tolerant drive is covered and simulation results are presented to verify operation of the proposed topology.

   Field Weakening Of Permanent Magnet Machines - Design Approaches
By T. A. Lipo And M. Aydin [View]
[Download]

Abstract: Permanent Magnet (PM) machines have been developed for numerous applications due to their attractive features especially after the development of NdFeB magnets. However, their complicated control lets the researchers develop new machine structures with easy field control. New alternative PM machine topologies with field weakening or hybrid excitation have been introduced in the literature for years to eliminate the effects of problems associated with the cumbersome field weakening techniques used in conventional PM machines. This paper reviews the field weakening of PM machines covered from machine’s perspective. Machine structures and features of each structure are clarified for both radial and axial airgap PM machines studied thus far.

   Generation Of Optimized Current Wave Forms For The Production Of Minimized Cogging Torque Of Transverse Flux Motors For Direct Drive Applications
By Marat Vinogradski, Uwe Werner, J. Schuettler, T. Petter, Bernd Orlik [View]
[Download]

Abstract: This paper deals with new and innovative methods to minimize the cogging torque of transverse flux motors. These approaches are based on the current wave form optimized for each phase of a two-phase transverse flux motor. The presented technique can be applied also to conventional machine types as, for example synchronous motors or switched reluctance motors.

   High Speed Motors With Active Magnetic Bearings
By Jiri Pavelka, Pavel Komarek, David Vydra [View]
[Download]

Abstract: The paper deals with the high speed bearingless motor development. Basic principles explanations, mathematical description, simulation results, realization steps, position sensors. The motor is intended for high-speed applications. Its principle is two poles synchronous permanent magnet motor with disk rotor.

   Modified Trapezoidal Modulating Signal Suitable For PM Synchronous Motor Drives
By Katsunori Taniguchi, Hiroyuki Yonezawa, Toshimitsu Morizane, Noriyuki Kimura [View]
[Download]

Abstract: A new modified trapezoidal modulating signal for pulse width modulation (PWM) inverter suitable for the Permanent Magnet synchronous motor (PMSM) drive is proposed in this paper. A new modulating signal for the PMSM drive is determined by the condition of reducing torque ripple of the motor with various electromotive force (EMF). Proposed modulating signal is able to decrease the torque ripple even if the motor has sinusoidal EMF or non-sinusoidal EMF. By using the proposed modulating signal, the system reduced the torque ripple as well as achieving the effective utilization of the DC supply voltage for the inverter. Many improvements are accomplished by the PWM strategy adapting the modified trapezoidal modulating signal without a change in hardware.

   Optimization Of PMSM For High-Torque And Field Weaking Mode
By Alexander Thaler [View]
[Download]

Abstract: While developing a permanent magnet machine for a small electrical vehicle (2.5kW) one has to take into account two basic design points. The low speed torque ability can be set through the air gap and the magnet materialassembled. The high speed ability is affected by the amount of armature reaction through stator current, which describes the ability to push the flux out of the region where first order voltage isinduced (field weakening). A rotor geometry has to be chosen for both low speed and high speed.

   Optimum Design Method For PM Motor From The Required Output NT Characteristics
By Kan Akatsu, Shinji Wakui [View]
[Download]

Abstract: Permanent Magnet Synchronous Motor (PMSM) has been widely used for the electric vehicle, the air compressor and so on. To use PMSM for the electric vehicle, the volume of it is very important, and more power and wider speed range are required. Though the inductance is very important parameter to realize the wider speed range, the design method of the inductance decided by the motor mechanical parameters D,L and so on has not been reported and the relationship between the inductance and the volume has not been cleared. In this paper, an optimum and an automatic design method for PMSM from the only required output characteristics is presented. This method is possible to obtain all motor mechanical parameters which realize minimum volume and which satisfy a maximum torque, speed, power and losses inputted by user. This paper clarified the relationship between the electrical parameters and the motor mechanical parameters, and this paper confirmed the output characteristics of the obtained motor by numerical simulation and Finite Element Method (FEM).

   Performance Analysis Of Vector Controlled Permanent Magnet Synchronous Motor With Fuzzy Tuned PID Controller
By Rajesh Kumar, R. A. Gupta, Bhim Singh [View]
[Download]

Abstract: This paper not only describes the development of fuzzy tuned PID controller for speed control but also presents a comprehensive analysis of vector controlled permanent magnet synchronous motor (PMSM) with said controller. A mathematical model of the drive is developed to study steady state and transient performance of current regulated voltage source Inverter (VSI) fed PMSM in the field-oriented mode under different conditions. The drive includes fuzzy tuned PID controller, vector control structure, the inverter and the machine. All the different segments of the drive are modelled separately and then integrated together to study dynamic behaviour of the drive scheme. Fuzzy rules and reasoning are utilized on line to determine controller parameters. The proposed scheme provides fast dynamic response in the closed loop operation of the drive especially in steady state condition. Simulation results obtained so far show improvement in response compared to conventional fixed gain PID controllers and other tuning schemes.

   Position Sensorless Control Of Interior Permanent Magnet Synchronous Motor Using Extended Electromotive Force
By Koji Tanaka, Ichiro Miki [View]
[Download]

Abstract: This paper presents a position sensorless control of interior permanent magnet synchronous motor (IPMSM). A mathematical model of IPMSM using an extended electromotive force (EMF) in the rotating reference frame is utilized to estimate the rotor position and speed. The estimation method is based on the principle that the estimation error of current is proportional to that of the extended EMF. The experimental results show the effectiveness of the proposed sensorless control.

   Self-Commissioning For Sensorless Field Oriented Control Of PM Motors
By H. Rasmussen [View]
[Download]

Abstract: Methods for estimation of the parameters in the inverter and the PM motor, based on special designed experiments, are given. Input to the system is the reference values for the stator voltages given as duty cycles for the Pulse With Modulated power device. The system output is the measured stator currents. Inverter parameters, stator resistance and inductance are measured at stand-still before the initial start-up of the drive. The strength of the permanent magnet is measured during a initial manual start-up of the drive. The measured parameters are used in a field oriented control system and the performance is experimentally verified.

   Sensorless Control Of Permanent Magnet Synchronous Machines - An Overview
By Manfred Schroedl [View]
[Download]

Abstract: Sensorless control of PMSMs has got considerable importance in drive research. After a short introduction about the operating modes of the PMSM, the paper gives an overview about the different approaches of sensorless position detection. Low speed and high speed models are explained. A special focus is given to methods with active signal excitation (signal injection, INFORM method).

   Sensorless Control Of Synchronous Motors Based On An Extended EMF Model And Inductance Measurement In The Model
By S. Ichikawa, M. Tomita, S. Doki, S. Okuma [View]
[Download]

Abstract: In this paper, a sensorless control method and an inductance measurement method for precise position estimation are proposed. The proposed sensorless control method that is based on an Extended EMF model can be applied for all kinds of synchronous motors without tuning. In the case motor parameters vary largely, accuracy of motor parameters is very important. Especially, change of inductance parameters is large because of magnetic saturation in SynRMs. To solve this problem, an inductance measurement method for precise position estimation is proposed using characteristics of the observer. This method can be also applied for PMSMs. Using the proposed system, sensorless control of synchronous reluctance motors can be realized.

   Sensorless Operation Methods For PM Motors
By D. Montesinos, S. Galceran, A. Sudria [View]
[Download]

Abstract: This paper provides a review of the literature addressing the sensorless operation of PM brushless machines. The methods explained are state-of-the-art, including those based on voltage and current measurements, and algebraic manipulations of machine equations, those based on back emf measurements, and those based on novel techniques not included in the previous categories. Starting strategies are also described.

   Synthesis And Optimisation Of Synchronous Electronically Commutated Motors
By J. Dirba, N. Roldugina [View]
[Download]

Abstract: The present publication is dedicated to the research of synchronous motors of various constructions, which can work in special modes together with a semi-conducting commutator and a rotor position sensor. The adjustment of supply voltage U1, excitation current I2 and load angle è is possible for such motors working with various load. This work presents developed synthesis and optimisation methodology of the above mentioned adjustment laws. This methodology is applicable to different types of electronically commutated motors: the traditional construction of salient and non-salient pole motors with an excitation winding and the contactless motors with permanent magnets, synchronous reluctance, inductor and claw-pole.

   Torque Ripples Calculation Of The Two-Phase Permanent Magnet Synchronous Motor Supplied By A Triac Converter From Single-Phase Voltage
By P. Zaskalicky, M. Zaskalicka [View]
[Download]

Abstract: A synchronous motor with ferrite rotor is a good solution for small pump applications. It also has some drawbacks. The most important of them seems to be its inability to start directly on the mains. Permanent magnet motor must to by equip with an electronic circuit for direct starting, which increases motor price. Another drawback is the torque ripple for the non-harmonic supply. This paper shown calculation of the torque ripple of the permanent magnet motor, which does a triac converter supply. The analytical method based on Fourier series is presented.

EPE-PEMC 2004 - Topic 05-1: Permanent magnet machines and drives
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2004 - Conference > EPE-PEMC 2004 - Topic 05: ELECTRICAL MACHINES AND ACTUATORS > EPE-PEMC 2004 - Topic 05-1: Permanent magnet machines and drives
	[return to parent folder]

	A Simple Initial Position Detecting Method For PMSMS By Means Of AC Excitation By Kazuhiko Ono, Hironori Hirato, Shoji Nishikata	[View] [Download]
Abstract: A new and simple detecting method of initial rotor position for permanent magnet synchronous motors without any position sensors is proposed. The intended method is based on observing the emf waveforms induced in the armature windings when a single-phase AC source is applied to one of the windings. ° The observation includes the comparison of the amplitudes and slopes of the emf waveforms in order to detect the rotor position. According to this method, initial rotor position can be detected every 30°. Finally, it is shown that the tested motor started successfully with the proposed position detecting method, confirming the usefulness of the method.

	Analytical Calculation Of Magnetic Field Distribution In The Slotted Air Gap Of A Surface PM Motor Using Complex Relative Air Gap Permeance By Damir Zarko, Thomas A. Lipo, Drago Ban	[View] [Download]
Abstract: An analytical method for calculation of no-load magnetic field distribution in the slotted air gap of a surface PM motor with radial or parallel magnetization is presented. The method introduces the notion of complex relative air gap permeance calculated from the conformal transformation of the slot geometry to take into account the effect of slotting. As a result an accurate solution of both radial and tangential components of the flux density can be obtained which shows excellent agreement with the results of finite element simulations. The effectiveness of the model has been shown on an example of a surface PM motor for which the back emf and the cogging torque waveforms have been calculated.

	Design Of A Novel Permanent Magnet Linear Actuator For Short-Stroke And High-Dynamic Motions By Steffen Braune, Steven Liu	[View] [Download]
Abstract: In this paper the design procedure of a novel permanent-magnet linear actuator is described. The main focusing point is to choose a proper geometry of the actuator components in order to meet the special specifications required by the intended application (very high dynamic, short-stroke, small volume and low power dissipation). Combined analytical and finite-element calculations are used to optimise the actuator performance. Calculation and simulation curves demonstrate the design results.

	Determination Of Resistive Parameters And Iron Losses In Vector Controlled PM Synchronous Motors With Rotor Saliency By M. Tursini, R. Petrella, T. Daloisio	[View] [Download]
Abstract: This paper presents a new approach to estimate the resistive parameters of the equivalent circuit in inverter-fed vector-controlled salient rotor permanent magnet synchronous motors. The method is based on the particular two-values shape of the loss power-vs.-current characteristic, when the motor is operated at constant output torque, constant speed and variable direct (d) current component. Such a profile allows to process the standard current/power/voltage measurements with a differential criteria, in order to minimize and theoretically cancel out the effects of non easily quantifiable phenomena, such as temperature, fundamental frequency, inverter feeding and additional losses. The presented method allows the contemporary estimation of the stator resistance and the iron losses equivalent resistor. A particular feature is that the resistive parameters are achieved in the practical operating conditions in the constant torque region. In fact they are identified near the minimum of the loss power-vs.-current characteristics, which is close to the maximum torque-to-current trajectory in the d-q currents plane. The paper covers the illustration of the basic elements of the method, some issues on the implementation problems, and the experimental results achieved on a motor-drive system for city-scooter application, which confirm the goodness of the proposal.

	Fault Interrupting Methods And Topologies For Interior PM Machine Drives By Brian A. Welchko, Thomas M. Jahns, Thomas A. Lipo	[View] [Download]
Abstract: This paper investigates methods to interrupt the phase currents induced when interior PM (IPM) motor drives suffer short-circuit or uncontrolled generator mode faults. A fault-tolerant silicon switch is proposed in which the antiparallel diode in a reverse-blocking IGBT is replaced in by an SCR. A reduced parts count fault interrupting topology is also proposed which consists of delta-connected thyristors inserted into the center of a wye-connected IPM motor stator. Control of the proposed reduced parts count fault-tolerant drive is covered and simulation results are presented to verify operation of the proposed topology.

	Field Weakening Of Permanent Magnet Machines - Design Approaches By T. A. Lipo And M. Aydin	[View] [Download]
Abstract: Permanent Magnet (PM) machines have been developed for numerous applications due to their attractive features especially after the development of NdFeB magnets. However, their complicated control lets the researchers develop new machine structures with easy field control. New alternative PM machine topologies with field weakening or hybrid excitation have been introduced in the literature for years to eliminate the effects of problems associated with the cumbersome field weakening techniques used in conventional PM machines. This paper reviews the field weakening of PM machines covered from machine’s perspective. Machine structures and features of each structure are clarified for both radial and axial airgap PM machines studied thus far.

	Generation Of Optimized Current Wave Forms For The Production Of Minimized Cogging Torque Of Transverse Flux Motors For Direct Drive Applications By Marat Vinogradski, Uwe Werner, J. Schuettler, T. Petter, Bernd Orlik	[View] [Download]
Abstract: This paper deals with new and innovative methods to minimize the cogging torque of transverse flux motors. These approaches are based on the current wave form optimized for each phase of a two-phase transverse flux motor. The presented technique can be applied also to conventional machine types as, for example synchronous motors or switched reluctance motors.

	High Speed Motors With Active Magnetic Bearings By Jiri Pavelka, Pavel Komarek, David Vydra	[View] [Download]
Abstract: The paper deals with the high speed bearingless motor development. Basic principles explanations, mathematical description, simulation results, realization steps, position sensors. The motor is intended for high-speed applications. Its principle is two poles synchronous permanent magnet motor with disk rotor.

	Modified Trapezoidal Modulating Signal Suitable For PM Synchronous Motor Drives By Katsunori Taniguchi, Hiroyuki Yonezawa, Toshimitsu Morizane, Noriyuki Kimura	[View] [Download]
Abstract: A new modified trapezoidal modulating signal for pulse width modulation (PWM) inverter suitable for the Permanent Magnet synchronous motor (PMSM) drive is proposed in this paper. A new modulating signal for the PMSM drive is determined by the condition of reducing torque ripple of the motor with various electromotive force (EMF). Proposed modulating signal is able to decrease the torque ripple even if the motor has sinusoidal EMF or non-sinusoidal EMF. By using the proposed modulating signal, the system reduced the torque ripple as well as achieving the effective utilization of the DC supply voltage for the inverter. Many improvements are accomplished by the PWM strategy adapting the modified trapezoidal modulating signal without a change in hardware.

	Optimization Of PMSM For High-Torque And Field Weaking Mode By Alexander Thaler	[View] [Download]
Abstract: While developing a permanent magnet machine for a small electrical vehicle (2.5kW) one has to take into account two basic design points. The low speed torque ability can be set through the air gap and the magnet materialassembled. The high speed ability is affected by the amount of armature reaction through stator current, which describes the ability to push the flux out of the region where first order voltage isinduced (field weakening). A rotor geometry has to be chosen for both low speed and high speed.

	Optimum Design Method For PM Motor From The Required Output NT Characteristics By Kan Akatsu, Shinji Wakui	[View] [Download]
Abstract: Permanent Magnet Synchronous Motor (PMSM) has been widely used for the electric vehicle, the air compressor and so on. To use PMSM for the electric vehicle, the volume of it is very important, and more power and wider speed range are required. Though the inductance is very important parameter to realize the wider speed range, the design method of the inductance decided by the motor mechanical parameters D,L and so on has not been reported and the relationship between the inductance and the volume has not been cleared. In this paper, an optimum and an automatic design method for PMSM from the only required output characteristics is presented. This method is possible to obtain all motor mechanical parameters which realize minimum volume and which satisfy a maximum torque, speed, power and losses inputted by user. This paper clarified the relationship between the electrical parameters and the motor mechanical parameters, and this paper confirmed the output characteristics of the obtained motor by numerical simulation and Finite Element Method (FEM).

	Performance Analysis Of Vector Controlled Permanent Magnet Synchronous Motor With Fuzzy Tuned PID Controller By Rajesh Kumar, R. A. Gupta, Bhim Singh	[View] [Download]
Abstract: This paper not only describes the development of fuzzy tuned PID controller for speed control but also presents a comprehensive analysis of vector controlled permanent magnet synchronous motor (PMSM) with said controller. A mathematical model of the drive is developed to study steady state and transient performance of current regulated voltage source Inverter (VSI) fed PMSM in the field-oriented mode under different conditions. The drive includes fuzzy tuned PID controller, vector control structure, the inverter and the machine. All the different segments of the drive are modelled separately and then integrated together to study dynamic behaviour of the drive scheme. Fuzzy rules and reasoning are utilized on line to determine controller parameters. The proposed scheme provides fast dynamic response in the closed loop operation of the drive especially in steady state condition. Simulation results obtained so far show improvement in response compared to conventional fixed gain PID controllers and other tuning schemes.

	Position Sensorless Control Of Interior Permanent Magnet Synchronous Motor Using Extended Electromotive Force By Koji Tanaka, Ichiro Miki	[View] [Download]
Abstract: This paper presents a position sensorless control of interior permanent magnet synchronous motor (IPMSM). A mathematical model of IPMSM using an extended electromotive force (EMF) in the rotating reference frame is utilized to estimate the rotor position and speed. The estimation method is based on the principle that the estimation error of current is proportional to that of the extended EMF. The experimental results show the effectiveness of the proposed sensorless control.

	Self-Commissioning For Sensorless Field Oriented Control Of PM Motors By H. Rasmussen	[View] [Download]
Abstract: Methods for estimation of the parameters in the inverter and the PM motor, based on special designed experiments, are given. Input to the system is the reference values for the stator voltages given as duty cycles for the Pulse With Modulated power device. The system output is the measured stator currents. Inverter parameters, stator resistance and inductance are measured at stand-still before the initial start-up of the drive. The strength of the permanent magnet is measured during a initial manual start-up of the drive. The measured parameters are used in a field oriented control system and the performance is experimentally verified.

	Sensorless Control Of Permanent Magnet Synchronous Machines - An Overview By Manfred Schroedl	[View] [Download]
Abstract: Sensorless control of PMSMs has got considerable importance in drive research. After a short introduction about the operating modes of the PMSM, the paper gives an overview about the different approaches of sensorless position detection. Low speed and high speed models are explained. A special focus is given to methods with active signal excitation (signal injection, INFORM method).

	Sensorless Control Of Synchronous Motors Based On An Extended EMF Model And Inductance Measurement In The Model By S. Ichikawa, M. Tomita, S. Doki, S. Okuma	[View] [Download]
Abstract: In this paper, a sensorless control method and an inductance measurement method for precise position estimation are proposed. The proposed sensorless control method that is based on an Extended EMF model can be applied for all kinds of synchronous motors without tuning. In the case motor parameters vary largely, accuracy of motor parameters is very important. Especially, change of inductance parameters is large because of magnetic saturation in SynRMs. To solve this problem, an inductance measurement method for precise position estimation is proposed using characteristics of the observer. This method can be also applied for PMSMs. Using the proposed system, sensorless control of synchronous reluctance motors can be realized.

	Sensorless Operation Methods For PM Motors By D. Montesinos, S. Galceran, A. Sudria	[View] [Download]
Abstract: This paper provides a review of the literature addressing the sensorless operation of PM brushless machines. The methods explained are state-of-the-art, including those based on voltage and current measurements, and algebraic manipulations of machine equations, those based on back emf measurements, and those based on novel techniques not included in the previous categories. Starting strategies are also described.

	Synthesis And Optimisation Of Synchronous Electronically Commutated Motors By J. Dirba, N. Roldugina	[View] [Download]
Abstract: The present publication is dedicated to the research of synchronous motors of various constructions, which can work in special modes together with a semi-conducting commutator and a rotor position sensor. The adjustment of supply voltage U1, excitation current I2 and load angle è is possible for such motors working with various load. This work presents developed synthesis and optimisation methodology of the above mentioned adjustment laws. This methodology is applicable to different types of electronically commutated motors: the traditional construction of salient and non-salient pole motors with an excitation winding and the contactless motors with permanent magnets, synchronous reluctance, inductor and claw-pole.

	Torque Ripples Calculation Of The Two-Phase Permanent Magnet Synchronous Motor Supplied By A Triac Converter From Single-Phase Voltage By P. Zaskalicky, M. Zaskalicka	[View] [Download]
Abstract: A synchronous motor with ferrite rotor is a good solution for small pump applications. It also has some drawbacks. The most important of them seems to be its inability to start directly on the mains. Permanent magnet motor must to by equip with an electronic circuit for direct starting, which increases motor price. Another drawback is the torque ripple for the non-harmonic supply. This paper shown calculation of the torque ripple of the permanent magnet motor, which does a triac converter supply. The analytical method based on Fourier series is presented.