EPE Association: EPE 2017 - DS2f: Electrical Machines and Drive Issues I

EPE 2017 - DS2f: Electrical Machines and Drive Issues I
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2017 ECCE Europe - Conference > EPE 2017 - Topic 04: Electrical Machines and Drive Systems > EPE 2017 - DS2f: Electrical Machines and Drive Issues I

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   A Review of Thermal Conductivity of Epoxy Composites Filled with Al2O3 or SiO2
By Josef SAMEK [View]
[Download]

Abstract: One way to improve properties of electrical machines is to enrich impregnating epoxy resin with Al2O3 or SiO2 nano- or micro- particles. This improves thermal conductivity of the insulation and reduces the temperature of a winding. The article reviews present work of scientists in the field of enrichment of the epoxy resins. Particle size influence is investigated and discussed same as usage of coupling agent. Experimental results are compared along scientific reports and new trend lines for further research are determined. Results of experiments promises improvements in efficiency of electrical machines, heat dissipation, dielectric strength and service life of insulating systems.

   Comparison of electromagnetic excited vibration for SPM and IPM motors
By JIANFENG HONG [View]
[Download]

Abstract: This paper compares the air gap field, magnetic radial force and vibration between SPM and IPM machines having 6-pole/54-slot winding topology together with the identical stator but different rotor topologies. A simplified analytical method is analyzed and its results are validate by Finite element method. It is shown that the vibration of the IPM is much higher than that in SPM when motor is in on-load due to significantly higher armature reaction.

   Compensation of Delay Time in the Current Control Loop of Field-Oriented Control
By Thomas HOLZMÜLLER [View]
[Download]

Abstract: This paper presents a model-based method to increase the dynamics of a current control loop within field-oriented control. The improvement is achieved by compensating for time delays within the control loop. The presented method is verified both through simulations using MATLAB/Simulink and with measurements using a rapid-control prototyping platform.

   Current controllers for drives: a theoretical and practical benchmark
By Radu LAZAR [View]
[Download]

Abstract: The current controller sets the base of the dynamical performance for drives running flux oriented control. In the literature, can be found different approaches used for the classical linear dq-current control. This paper has as aim a theoretical and practical benchmark of the diverse types of linear controllers suitable for drive application. There are evaluated different properties like: dynamical performance, complexity and parameter sensitivity. In the conclusion, there will be made a recommendation about how to choose the best controller for the job.

   Development of testing methods for winding turn-to-turn insulation of low voltage motors fed by PWM converters
By Veronika BOLGOVA [View]
[Download]

Abstract: Electrical insulation materials quality and reliability play a central role in providing the electrical machines reliable operation. It is well recognized that insulating system of low voltage motor fed by converter is exposed to electrical stresses arising from repetitive square waveform of supplying voltage while additional impact of temperature, vibrations and environmental operation conditions are imposed. The implementation of wide bandgap power semiconductors as SiC and GaN in recent years allows to create very powerful converters with high switching speed. On the other hand it leads to a remarkable increasing electro-thermal constraints applied to windings' turn-to-turn insulation of motors fed by such converters. The relevance of new testing methods and test benches is well found by remarkable modern advances in semiconductors technology. Testing methods for low voltage motors winding wires insulation proposed in this paper permit to evaluate the withstand capability of insulation materials applying the high frequency modulated signals representative for traditional converters supplying (µs level of impulse rise/fall time), as well as the voltage waveforms with very straight adjustable dV/dt, very fast rise time and fall time (ns level of impulse rise/fall time) engendered by new semiconductor devices based on wide bandgap materials. The possibility to modify experiment parameters in wide rage for insulation endurance tests allows to obtain a rich data for further analysis.

   Efficiency Improvement and Downsizing of Double-Layered IPMSMs Containing a Strong Magnet for Automotive Applications
By Yuki SHIMIZU [View]
[Download]

Abstract: Interior permanent magnet synchronous motors (IPMSMs) are currently widely utilized as traction motors. The permanent magnets used in IPMSMs are an important factor; thus, high-coercivity permanent magnets with lesser rare-earth elements are in development. This paper proposes two modified versions of double-layered IPMSMs containing a strong magnet to improve their efficiency and reduce their size. The performance of these IPMSMs is demonstrated in several scenarios and discussed based on the results of two-dimensional finite element analysis.

   Induction Motor Stator Current Spectral Content under Sinusoidal and PWM Excitation
By Lassi AARNIOVUORI [View]
[Download]

Abstract: The use of converters to feed motors instead of the direct-on-line supply has increased the need tounderstand the behaviour of the induction machine in different operating points. The additional lossesin frequency converter fed machines are caused by the harmonic content of a PWM voltage excitation.This paper investigates closely the harmonic contents of stator supply voltage and current. Most of theearlier studies have focused on sinusoidal supply or converter supply in only a few specific load pointswhile this study covers most of the frequency-torque plane below nominal values. A 15 kW standardsquirrel-cage machine's stator current and voltage time functions and spectra are analysed in 16 differentoperating points with torque values of 25 \%, 50 \%, 75 \% and 100 \% of the motor's rated torque andsupply frequency values of 25 \%, 50 \%, 75 \% and 100 \% of the motor's rated frequency. Measurementsin all 16 operating points are performed with both sinusoidal generator supply and with a frequencyconverter supply.

   Integrated Motor Controlled by Multi-Inverter with Pole-Changing Functionality and Fault Tolerance
By Kazuto SAKAI [View]
[Download]

Abstract: Energy saving is arguably the most important factor in issues regarding energy and carbon emission. For electric vehicles in particular, saving energy extends the driving range. This can be achieved with a highly efficient variable-speed drive that can cover a wide speed range, and changing the number of poles is one way of realizing such a drive. In addition, electric vehicles must be fault tolerant so that they can still be driven in the event that some components fail. To achieve high performance with pole changing, fault tolerance, and low torque ripple, a motor with two winding groups is combined with two inverters and operated using individual current control. Our results confirm that changing the number of poles allows the motor to operate over a wide speed range in excess of five times the base speed. The new motor has half the torque ripple of a conventional machine and can also continue to drive even if one inverter breaks down.

   Load angle estimation in dynamic stepping motor applications based on Phase Locked Loop
By Jasper DE VIAENE [View]
[Download]

Abstract: Stepping motors are well suited for open-loop positioning tasks at low-power. The rotor position of the machine can simply be controlled by the user. Every time a next pulse is sent by the user, the stepping motor driver excites the correct stator phases to rotate the rotor over a pre-defined discrete angular position. In this way, counting the step command pulses enables open-loop positioning. However, when the motor is overloaded or stuck, the relation between the expected rotor position based on the number of step command pulses and the actual rotor position is lost. This is called step loss. Open-loop stepping motor methodologies do not detect this step loss or stall. While the absolute rotor position is lost, the open-loop control continues to send unnecessary and unwanted step command pulses. This can lead to excessive vibrations, wear and noise. Especially for dynamically demanding applications, step loss should be avoided or at least be detected. Using a mechanical position sensor to achieve closed loop control would increase the cost and complexity of the system and omits the straightforward open loop control. Therefore in this paper, a sensorless estimator based on a Phase Locked Loop is presented which provides feedback of the load angle, even during transients. The load angle contains information about the torque generation and the margin to step loss. To estimate the load angle, the back-EMF is considered. This algorithm can be used with the typical full-, half- and micro-stepping algorithm and only needs one current and one voltage measurement and electrical parameters such as resistance and inductance to estimate the back-EMF and subsequently estimate the load angle. The proposed algorithm is validated through measurements on a hybrid stepper motor.

   Methodology for Experimental Measurement of Force Acting on Eccentric Rotor of Electric Machine
By Vladimír KINDL [View]
[Download]

Abstract: The paper proposes an experimental methodology for measurement of forces acting on the rotor under special operational conditions. The influence of static eccentricity with different load applied on the rotor is investigated. The paper also describes all necessary motor construction modifications and the procedure of preliminary measuring system calibration.

   Parameter Identification of a Dual Stator Induction Machine
By Moritz HAUSSMANN [View]
[Download]

Abstract: This paper presents a set of system equations of a dual stator induction machine (DSIM) and a newapproach for online parameter identification including its verification through simulation and measurements.An uneven current share between the two three-phase systems of a DSIM is used to determinemachine parameters online.

   Two-phase transverse flux machine with disc rotor for high torque low speed application
By Sebastian HIEKE [View]
[Download]

Abstract: This paper presents a special two-phase transverse flux machine with disc rotor. Because of the noncomplexconstruction and by using simple 2D flux path and 3D printing methods the manufacturing costs arehold low. A design criterion is proposed for maximizing the torque density in the low speed range. Toprove the concept and analyse the potential of this construction a first direct driven prototype was built.The experimental results confirm the viability of this proposal and provide the required information forfurther enhancements.

EPE 2017 - DS2f: Electrical Machines and Drive Issues I
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2017 ECCE Europe - Conference > EPE 2017 - Topic 04: Electrical Machines and Drive Systems > EPE 2017 - DS2f: Electrical Machines and Drive Issues I
	[return to parent folder]

	A Review of Thermal Conductivity of Epoxy Composites Filled with Al2O3 or SiO2 By Josef SAMEK	[View] [Download]
Abstract: One way to improve properties of electrical machines is to enrich impregnating epoxy resin with Al2O3 or SiO2 nano- or micro- particles. This improves thermal conductivity of the insulation and reduces the temperature of a winding. The article reviews present work of scientists in the field of enrichment of the epoxy resins. Particle size influence is investigated and discussed same as usage of coupling agent. Experimental results are compared along scientific reports and new trend lines for further research are determined. Results of experiments promises improvements in efficiency of electrical machines, heat dissipation, dielectric strength and service life of insulating systems.

	Comparison of electromagnetic excited vibration for SPM and IPM motors By JIANFENG HONG	[View] [Download]
Abstract: This paper compares the air gap field, magnetic radial force and vibration between SPM and IPM machines having 6-pole/54-slot winding topology together with the identical stator but different rotor topologies. A simplified analytical method is analyzed and its results are validate by Finite element method. It is shown that the vibration of the IPM is much higher than that in SPM when motor is in on-load due to significantly higher armature reaction.

	Compensation of Delay Time in the Current Control Loop of Field-Oriented Control By Thomas HOLZMÜLLER	[View] [Download]
Abstract: This paper presents a model-based method to increase the dynamics of a current control loop within field-oriented control. The improvement is achieved by compensating for time delays within the control loop. The presented method is verified both through simulations using MATLAB/Simulink and with measurements using a rapid-control prototyping platform.

	Current controllers for drives: a theoretical and practical benchmark By Radu LAZAR	[View] [Download]
Abstract: The current controller sets the base of the dynamical performance for drives running flux oriented control. In the literature, can be found different approaches used for the classical linear dq-current control. This paper has as aim a theoretical and practical benchmark of the diverse types of linear controllers suitable for drive application. There are evaluated different properties like: dynamical performance, complexity and parameter sensitivity. In the conclusion, there will be made a recommendation about how to choose the best controller for the job.

	Development of testing methods for winding turn-to-turn insulation of low voltage motors fed by PWM converters By Veronika BOLGOVA	[View] [Download]
Abstract: Electrical insulation materials quality and reliability play a central role in providing the electrical machines reliable operation. It is well recognized that insulating system of low voltage motor fed by converter is exposed to electrical stresses arising from repetitive square waveform of supplying voltage while additional impact of temperature, vibrations and environmental operation conditions are imposed. The implementation of wide bandgap power semiconductors as SiC and GaN in recent years allows to create very powerful converters with high switching speed. On the other hand it leads to a remarkable increasing electro-thermal constraints applied to windings' turn-to-turn insulation of motors fed by such converters. The relevance of new testing methods and test benches is well found by remarkable modern advances in semiconductors technology. Testing methods for low voltage motors winding wires insulation proposed in this paper permit to evaluate the withstand capability of insulation materials applying the high frequency modulated signals representative for traditional converters supplying (µs level of impulse rise/fall time), as well as the voltage waveforms with very straight adjustable dV/dt, very fast rise time and fall time (ns level of impulse rise/fall time) engendered by new semiconductor devices based on wide bandgap materials. The possibility to modify experiment parameters in wide rage for insulation endurance tests allows to obtain a rich data for further analysis.

	Efficiency Improvement and Downsizing of Double-Layered IPMSMs Containing a Strong Magnet for Automotive Applications By Yuki SHIMIZU	[View] [Download]
Abstract: Interior permanent magnet synchronous motors (IPMSMs) are currently widely utilized as traction motors. The permanent magnets used in IPMSMs are an important factor; thus, high-coercivity permanent magnets with lesser rare-earth elements are in development. This paper proposes two modified versions of double-layered IPMSMs containing a strong magnet to improve their efficiency and reduce their size. The performance of these IPMSMs is demonstrated in several scenarios and discussed based on the results of two-dimensional finite element analysis.

	Induction Motor Stator Current Spectral Content under Sinusoidal and PWM Excitation By Lassi AARNIOVUORI	[View] [Download]
Abstract: The use of converters to feed motors instead of the direct-on-line supply has increased the need tounderstand the behaviour of the induction machine in different operating points. The additional lossesin frequency converter fed machines are caused by the harmonic content of a PWM voltage excitation.This paper investigates closely the harmonic contents of stator supply voltage and current. Most of theearlier studies have focused on sinusoidal supply or converter supply in only a few specific load pointswhile this study covers most of the frequency-torque plane below nominal values. A 15 kW standardsquirrel-cage machine's stator current and voltage time functions and spectra are analysed in 16 differentoperating points with torque values of 25 \%, 50 \%, 75 \% and 100 \% of the motor's rated torque andsupply frequency values of 25 \%, 50 \%, 75 \% and 100 \% of the motor's rated frequency. Measurementsin all 16 operating points are performed with both sinusoidal generator supply and with a frequencyconverter supply.

	Integrated Motor Controlled by Multi-Inverter with Pole-Changing Functionality and Fault Tolerance By Kazuto SAKAI	[View] [Download]
Abstract: Energy saving is arguably the most important factor in issues regarding energy and carbon emission. For electric vehicles in particular, saving energy extends the driving range. This can be achieved with a highly efficient variable-speed drive that can cover a wide speed range, and changing the number of poles is one way of realizing such a drive. In addition, electric vehicles must be fault tolerant so that they can still be driven in the event that some components fail. To achieve high performance with pole changing, fault tolerance, and low torque ripple, a motor with two winding groups is combined with two inverters and operated using individual current control. Our results confirm that changing the number of poles allows the motor to operate over a wide speed range in excess of five times the base speed. The new motor has half the torque ripple of a conventional machine and can also continue to drive even if one inverter breaks down.

	Load angle estimation in dynamic stepping motor applications based on Phase Locked Loop By Jasper DE VIAENE	[View] [Download]
Abstract: Stepping motors are well suited for open-loop positioning tasks at low-power. The rotor position of the machine can simply be controlled by the user. Every time a next pulse is sent by the user, the stepping motor driver excites the correct stator phases to rotate the rotor over a pre-defined discrete angular position. In this way, counting the step command pulses enables open-loop positioning. However, when the motor is overloaded or stuck, the relation between the expected rotor position based on the number of step command pulses and the actual rotor position is lost. This is called step loss. Open-loop stepping motor methodologies do not detect this step loss or stall. While the absolute rotor position is lost, the open-loop control continues to send unnecessary and unwanted step command pulses. This can lead to excessive vibrations, wear and noise. Especially for dynamically demanding applications, step loss should be avoided or at least be detected. Using a mechanical position sensor to achieve closed loop control would increase the cost and complexity of the system and omits the straightforward open loop control. Therefore in this paper, a sensorless estimator based on a Phase Locked Loop is presented which provides feedback of the load angle, even during transients. The load angle contains information about the torque generation and the margin to step loss. To estimate the load angle, the back-EMF is considered. This algorithm can be used with the typical full-, half- and micro-stepping algorithm and only needs one current and one voltage measurement and electrical parameters such as resistance and inductance to estimate the back-EMF and subsequently estimate the load angle. The proposed algorithm is validated through measurements on a hybrid stepper motor.

	Methodology for Experimental Measurement of Force Acting on Eccentric Rotor of Electric Machine By Vladimír KINDL	[View] [Download]
Abstract: The paper proposes an experimental methodology for measurement of forces acting on the rotor under special operational conditions. The influence of static eccentricity with different load applied on the rotor is investigated. The paper also describes all necessary motor construction modifications and the procedure of preliminary measuring system calibration.

	Parameter Identification of a Dual Stator Induction Machine By Moritz HAUSSMANN	[View] [Download]
Abstract: This paper presents a set of system equations of a dual stator induction machine (DSIM) and a newapproach for online parameter identification including its verification through simulation and measurements.An uneven current share between the two three-phase systems of a DSIM is used to determinemachine parameters online.

	Two-phase transverse flux machine with disc rotor for high torque low speed application By Sebastian HIEKE	[View] [Download]
Abstract: This paper presents a special two-phase transverse flux machine with disc rotor. Because of the noncomplexconstruction and by using simple 2D flux path and 3D printing methods the manufacturing costs arehold low. A design criterion is proposed for maximizing the torque density in the low speed range. Toprove the concept and analyse the potential of this construction a first direct driven prototype was built.The experimental results confirm the viability of this proposal and provide the required information forfurther enhancements.