EPE Association: EPE 1989 - 02 - Lecture Session 1.2: ADJUSTABLE SPEED DRIVES

EPE 1989 - 02 - Lecture Session 1.2: ADJUSTABLE SPEED DRIVES
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1989 - Conference > EPE 1989 - 02 - Lecture Session 1.2: ADJUSTABLE SPEED DRIVES

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   THE DESIGN AND PERFORMANCE OF A MULTIPHASE SWITCHED RELUCTANCE DRIVE
By C. Pollock; B. W. Williams [View]
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Abstract: Reluctance motors with more than four phase windings offer improved low speed performance due to the smaller step-angles but have previously been considered uneconomic due to the large number of semiconductor switches required. A novel power converter circuit has been developed which uses switches rated at the same voltage as the motor windings but has less than two switches per phase winding. Reluctance motors with an odd number of phase windings can be connected to this power converter and such motors are shown to offer improved performance with shorter flux paths in the motor and multiple stepping modes. The design of a four kilowatt seven phase switched reluctance drive is described and test results are presented.

   THE CONTROL OF SR DRIVES: REVIEW AND CURRENT STATUS
By D. M. Sugden; P. D. Webster; J. M. Stephenson [View]
[Download]

Abstract: This paper discusses the basic control strategy for a switched reluctance drive. A review of the published material by various authors is then presented. Control systems using discrete analogue, microprocessor end ASIC implementations are described and compared. The operation and performance of a current state-of-the-art digital control system designed by the authors is then described. Finally, the paper presents details of the performance of two switched reluctance drives using this control system in the application areas of general purpose industrial drives and position control servo drives.

   EVOLUTION OF HIGH POWER DRIVES FOR HIGH SPEED INDUCTION MOTORS
By Jean-Marie Andrejak [View]
[Download]

Abstract: The concurrent evolution of power electronics and "high speed" induction motors is setting new power-speed limits for electrical drives. lt provides answers to the well-known requirements of equipment with power ratings from 1 to 2 MW and speeds from 10,000 to 20,000 rpm intended to replace steam or gas turbines. A number of solutions are discussed that use either series-connected GTOs or parallel-connected inverters. A technical and economic comparison is made.

   INCREASE OF POWER AND REDUCTION OF NOISE AND CURRENT RIPPLE OF INVERTER FED INDUCTION MACHINES
By G. Hupe; Dr. R. Kennel [View]
[Download]

Abstract: The fast development and high reliability of quick and powerful bipolar transistors, the development of fast and cheap microcomputers gives the possibility of designing electrical drives with asynchronous motors with a high dynamic quality and a power range of 100 kW. In comparison with DC drives the great advantages of these new drives are:
1. Cheaper and maintenance free motors (no comutator necessary)
2. Higher protection standard - IP 54 and more.
During the last few years brushless AC drives more and more claimed modern machine tool applications. This paper proposes a possibility to increase the power of existing drives and to reduce simultaneously noise and current ripple of inverter fed induction machines by a special manner of controlling and splitting the inverter currents.

   ROTOR DESIGN FOR INVERTOR-FED HIGH SPEED INDUCTION MOTORS
By L. Gertmar; C. Sadarangani; M. Johansson [View]
[Download]

Abstract: This paper presents 2 different rotor slot shapes suitable for invertor-fed induction motors. The first slot has an U-shaped bridge at the bottom of the slot opening. The U-shaped bridge greatly reduces the rotor resistance at high frequencies at the same time increasing the rotor leakage inductance. The harmonic copper losses are therefore considerably reduced. The second slot has an iron bridge with a narrow slit suitably designed to control the saturation level. This slot shape gives high differential leakage resistance at reduced currents. For high speed self-ventilated drives this property can be utilized at lower speeds to extract a higher power level for the same motor frame size. Theoretical studies on the 2 slots are presented. An experimental setup and measurement method is described. Results from the measurement on motor drives with the different slot shapes are presented to verify the claims.

   DEVELOPMENT OF DIFFERENT TYPES OF POWER-ELECTRONIC-CONTROLLED ROBOTIC DRIVES
By H.-J. Gutt; R. Lust [View]
[Download]

Abstract: The main advantage of electric robotic drives is their easy and fast electronic-power control: Beginning with the supply of d.c. motors by controlled rectifier-bridges the d.c. commutator-machine changed from the cylindric-rotor to the disc-rotor-type, especially for robotic-arm-drives where extremely short motors are required. With the increasing power density of permanent magnet materials the brushless "synchronous"-respectively e.c. motors were developed. For main axes there is a trend to direct drives with switched reluctance motors, in future perhaps liquid cooled. A general trend goes to slotless permanent-magnet-excited drives with air gap windings, because they may give as well very high positioning accuracy at low speed as very low losses at high-speed running. Another trend goes to the intelligent drive system, demonstrated with a thermal-protection-system.

EPE 1989 - 02 - Lecture Session 1.2: ADJUSTABLE SPEED DRIVES
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1989 - Conference > EPE 1989 - 02 - Lecture Session 1.2: ADJUSTABLE SPEED DRIVES
	[return to parent folder]

	THE DESIGN AND PERFORMANCE OF A MULTIPHASE SWITCHED RELUCTANCE DRIVE By C. Pollock; B. W. Williams	[View] [Download]
Abstract: Reluctance motors with more than four phase windings offer improved low speed performance due to the smaller step-angles but have previously been considered uneconomic due to the large number of semiconductor switches required. A novel power converter circuit has been developed which uses switches rated at the same voltage as the motor windings but has less than two switches per phase winding. Reluctance motors with an odd number of phase windings can be connected to this power converter and such motors are shown to offer improved performance with shorter flux paths in the motor and multiple stepping modes. The design of a four kilowatt seven phase switched reluctance drive is described and test results are presented.

	THE CONTROL OF SR DRIVES: REVIEW AND CURRENT STATUS By D. M. Sugden; P. D. Webster; J. M. Stephenson	[View] [Download]
Abstract: This paper discusses the basic control strategy for a switched reluctance drive. A review of the published material by various authors is then presented. Control systems using discrete analogue, microprocessor end ASIC implementations are described and compared. The operation and performance of a current state-of-the-art digital control system designed by the authors is then described. Finally, the paper presents details of the performance of two switched reluctance drives using this control system in the application areas of general purpose industrial drives and position control servo drives.

	EVOLUTION OF HIGH POWER DRIVES FOR HIGH SPEED INDUCTION MOTORS By Jean-Marie Andrejak	[View] [Download]
Abstract: The concurrent evolution of power electronics and "high speed" induction motors is setting new power-speed limits for electrical drives. lt provides answers to the well-known requirements of equipment with power ratings from 1 to 2 MW and speeds from 10,000 to 20,000 rpm intended to replace steam or gas turbines. A number of solutions are discussed that use either series-connected GTOs or parallel-connected inverters. A technical and economic comparison is made.

	INCREASE OF POWER AND REDUCTION OF NOISE AND CURRENT RIPPLE OF INVERTER FED INDUCTION MACHINES By G. Hupe; Dr. R. Kennel	[View] [Download]
Abstract: The fast development and high reliability of quick and powerful bipolar transistors, the development of fast and cheap microcomputers gives the possibility of designing electrical drives with asynchronous motors with a high dynamic quality and a power range of 100 kW. In comparison with DC drives the great advantages of these new drives are: 1. Cheaper and maintenance free motors (no comutator necessary) 2. Higher protection standard - IP 54 and more. During the last few years brushless AC drives more and more claimed modern machine tool applications. This paper proposes a possibility to increase the power of existing drives and to reduce simultaneously noise and current ripple of inverter fed induction machines by a special manner of controlling and splitting the inverter currents.

	ROTOR DESIGN FOR INVERTOR-FED HIGH SPEED INDUCTION MOTORS By L. Gertmar; C. Sadarangani; M. Johansson	[View] [Download]
Abstract: This paper presents 2 different rotor slot shapes suitable for invertor-fed induction motors. The first slot has an U-shaped bridge at the bottom of the slot opening. The U-shaped bridge greatly reduces the rotor resistance at high frequencies at the same time increasing the rotor leakage inductance. The harmonic copper losses are therefore considerably reduced. The second slot has an iron bridge with a narrow slit suitably designed to control the saturation level. This slot shape gives high differential leakage resistance at reduced currents. For high speed self-ventilated drives this property can be utilized at lower speeds to extract a higher power level for the same motor frame size. Theoretical studies on the 2 slots are presented. An experimental setup and measurement method is described. Results from the measurement on motor drives with the different slot shapes are presented to verify the claims.

	DEVELOPMENT OF DIFFERENT TYPES OF POWER-ELECTRONIC-CONTROLLED ROBOTIC DRIVES By H.-J. Gutt; R. Lust	[View] [Download]
Abstract: The main advantage of electric robotic drives is their easy and fast electronic-power control: Beginning with the supply of d.c. motors by controlled rectifier-bridges the d.c. commutator-machine changed from the cylindric-rotor to the disc-rotor-type, especially for robotic-arm-drives where extremely short motors are required. With the increasing power density of permanent magnet materials the brushless "synchronous"-respectively e.c. motors were developed. For main axes there is a trend to direct drives with switched reluctance motors, in future perhaps liquid cooled. A general trend goes to slotless permanent-magnet-excited drives with air gap windings, because they may give as well very high positioning accuracy at low speed as very low losses at high-speed running. Another trend goes to the intelligent drive system, demonstrated with a thermal-protection-system.