EPE Association: EPE 2001 - Topic 06i: Converter Machine Interactions

EPE 2001 - Topic 06i: Converter Machine Interactions
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2001 - Conference > EPE 2001 - Topic 06: ELECTRICAL MACHINES AND ADJUSTABLE SPEED DRIVES > EPE 2001 - Topic 06i: Converter Machine Interactions

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   A PWM control strategy for reducing acoustic noise
By A. Hubert; G. Friedrich [View]
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Abstract: Acoustic noise generated by the association of an electric machine and its converter becomes of prime importance for choosing an electrical drive. Most studies deal with the electromechanical aspects (radial stress on the stator) and mechanical aspects (vibrations and acoustic) in a disassociated way. The presented study proposes to treat the whole problem with one same tool, based on the rotating field theory and a two-dimensions associated spectrum analysis. The aim is to find a control strategy and its parameters (e.g. chopping frequency) associated with electromechanical (slot number and aperture, winding type) and mechanical machine characteristics. The paper is illustrated by an example using a 1.25 kW induction machine associated with a natural sampling power converter.

   Common-Mode Voltage in PWM Rectifier-Inverter systems
By S. Fillet Castella; J. Bergas; S. Galceran; A. Sudria; J. Rull [View]
[Download]

Abstract: A lot of effort has gone into reducing common-mode voltage in three phase PWM voltage-source inverters (PWM-VSI). The rectifier effects are not usually taken into consideration. This can be reasonable with diode rectifiers, where dc-link voltage is maintained almost constant with respect to network neutral. The importance of considering rectifier-side with PWM rectifiers is the object of this paper.

   Effect of Cycloconverter on Properties of Doubly Fed Machine
By J. Bendl; M. Chomát; L. Schreier [View]
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Abstract: The paper concerns a rise of higher harmonics in currents and voltages of a doubly fed machine that are caused by operation of a cycloconverter in the rotor circuit. The currents in the transformer of the cycloconverter are also analyzed as they can affect the rated power of the transformer. The results will be used in the design and development of a practical unit with an adjustable speed motorgenerator for a storage power plant.

   Modeling and Evaluation of dv/dt Filters for ASD
By A. F. Moreira; T. A. Lipo; G. Venkataramanan; S. Bernet [View]
[Download]

Abstract: Recent advances in power electronic switching device technology have resulted in dramatic improvements and cost reduction of pulse-width modulated AC adjustable speed drives. Concomitant with the better performance enabled by the high switching speed and increased switching frequency they have also raised several concerns related to the consequences of high speed switching. One of these concerns is the over-voltage that appears at the motor terminals due to the impedance mismatch between the power cable and the motor. This paper develops accurate simulation models for power cables and motors that allow a better understanding of the over-voltage problem. The models can be readily implemented using computational tools like Matlab, thereby providing a convenient method to develop the best dv/dt filter solution for a particular drive. The power cable is modeled using several lumped-parameter segments of a lossy representation of transmission line. An algebraic analysis is developed to choose an adequate number of lumped-parameter segments. The number of required segment is function of the pulse rise time, cable characteristic parameters and cable length. Simulation results are presented analyzing the over-voltage problem for a wide range of pulse rise times and cable lengths for 1hp, 10hp and 100hp motors. The most important filter network solutions are investigated using the simulation program and an optimized design is performed for the RC Filter at the motor terminals. Experimental results verifying the validity of the model for the over-voltage analysis are presented.

   Single Phase Mains Supplied Variable Speed Induction Motor Drive
By P. Lürkens [View]
[Download]

Abstract: A new control method allows to operate a 3-phase induction motor with a simple voltage source inverter from the single-phase mains with low mains harmonics at a wide speed range. No electrolytic capacitors are required anymore. Even the torque ripple can be low. The control method implements a kind of inverse compensation of the DC bus voltage which removes all frequency components from the motor phase voltage except two, symmetrical to the modulator frequency.

   Unipolar converter for brushless DC motor
By A. Consoli; S. De Caro; A. Testa; N. Aiello; F. Gennaro; M. Lo Presti [View]
[Download]

Abstract: Unipolar power converters allow to reduce cost and circuital complexity of DC brushless motor drives by reducing the number of required power switches per phase. A new converter topology is presented that allows to improve the power factor of unipolar DC Brushless Motor drives, aimed to equip low cost variable speed drives. It features an unipolar topology with a modified C-dump energy recovery stage, that allows to perform an active power factor control. According to the presented approach no additional power factor control stages are necessary to comply with power quality requirements. Moreover, the proposed converter topology featuring only low side switches, allows to simplify the switch control circuits and opens the perspective of integrate all the converter on a single chip exploiting smart power technologies.

EPE 2001 - Topic 06i: Converter Machine Interactions
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2001 - Conference > EPE 2001 - Topic 06: ELECTRICAL MACHINES AND ADJUSTABLE SPEED DRIVES > EPE 2001 - Topic 06i: Converter Machine Interactions
	[return to parent folder]

	A PWM control strategy for reducing acoustic noise By A. Hubert; G. Friedrich	[View] [Download]
Abstract: Acoustic noise generated by the association of an electric machine and its converter becomes of prime importance for choosing an electrical drive. Most studies deal with the electromechanical aspects (radial stress on the stator) and mechanical aspects (vibrations and acoustic) in a disassociated way. The presented study proposes to treat the whole problem with one same tool, based on the rotating field theory and a two-dimensions associated spectrum analysis. The aim is to find a control strategy and its parameters (e.g. chopping frequency) associated with electromechanical (slot number and aperture, winding type) and mechanical machine characteristics. The paper is illustrated by an example using a 1.25 kW induction machine associated with a natural sampling power converter.

	Common-Mode Voltage in PWM Rectifier-Inverter systems By S. Fillet Castella; J. Bergas; S. Galceran; A. Sudria; J. Rull	[View] [Download]
Abstract: A lot of effort has gone into reducing common-mode voltage in three phase PWM voltage-source inverters (PWM-VSI). The rectifier effects are not usually taken into consideration. This can be reasonable with diode rectifiers, where dc-link voltage is maintained almost constant with respect to network neutral. The importance of considering rectifier-side with PWM rectifiers is the object of this paper.

	Effect of Cycloconverter on Properties of Doubly Fed Machine By J. Bendl; M. Chomát; L. Schreier	[View] [Download]
Abstract: The paper concerns a rise of higher harmonics in currents and voltages of a doubly fed machine that are caused by operation of a cycloconverter in the rotor circuit. The currents in the transformer of the cycloconverter are also analyzed as they can affect the rated power of the transformer. The results will be used in the design and development of a practical unit with an adjustable speed motorgenerator for a storage power plant.

	Modeling and Evaluation of dv/dt Filters for ASD By A. F. Moreira; T. A. Lipo; G. Venkataramanan; S. Bernet	[View] [Download]
Abstract: Recent advances in power electronic switching device technology have resulted in dramatic improvements and cost reduction of pulse-width modulated AC adjustable speed drives. Concomitant with the better performance enabled by the high switching speed and increased switching frequency they have also raised several concerns related to the consequences of high speed switching. One of these concerns is the over-voltage that appears at the motor terminals due to the impedance mismatch between the power cable and the motor. This paper develops accurate simulation models for power cables and motors that allow a better understanding of the over-voltage problem. The models can be readily implemented using computational tools like Matlab, thereby providing a convenient method to develop the best dv/dt filter solution for a particular drive. The power cable is modeled using several lumped-parameter segments of a lossy representation of transmission line. An algebraic analysis is developed to choose an adequate number of lumped-parameter segments. The number of required segment is function of the pulse rise time, cable characteristic parameters and cable length. Simulation results are presented analyzing the over-voltage problem for a wide range of pulse rise times and cable lengths for 1hp, 10hp and 100hp motors. The most important filter network solutions are investigated using the simulation program and an optimized design is performed for the RC Filter at the motor terminals. Experimental results verifying the validity of the model for the over-voltage analysis are presented.

	Single Phase Mains Supplied Variable Speed Induction Motor Drive By P. Lürkens	[View] [Download]
Abstract: A new control method allows to operate a 3-phase induction motor with a simple voltage source inverter from the single-phase mains with low mains harmonics at a wide speed range. No electrolytic capacitors are required anymore. Even the torque ripple can be low. The control method implements a kind of inverse compensation of the DC bus voltage which removes all frequency components from the motor phase voltage except two, symmetrical to the modulator frequency.

	Unipolar converter for brushless DC motor By A. Consoli; S. De Caro; A. Testa; N. Aiello; F. Gennaro; M. Lo Presti	[View] [Download]
Abstract: Unipolar power converters allow to reduce cost and circuital complexity of DC brushless motor drives by reducing the number of required power switches per phase. A new converter topology is presented that allows to improve the power factor of unipolar DC Brushless Motor drives, aimed to equip low cost variable speed drives. It features an unipolar topology with a modified C-dump energy recovery stage, that allows to perform an active power factor control. According to the presented approach no additional power factor control stages are necessary to comply with power quality requirements. Moreover, the proposed converter topology featuring only low side switches, allows to simplify the switch control circuits and opens the perspective of integrate all the converter on a single chip exploiting smart power technologies.