EPE Association: NORpie 1998 - Topic 08: POSTERS

NORpie 1998 - Topic 08: POSTERS
You are here: EPE Documents > 05 - EPE Supported Conference Proceedings > NORpie - Proceedings > NORpie 1998 > NORpie 1998 - Topic 08: POSTERS

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   General Purpose Mechatronic Modules on the Base of Direct Converters and Induction Motors
By V. I. Chrisanov; YUL N. Konovalov [View]
[Download]

Abstract: The paper presents the results of R&D work on mechatronic modules, consisted of thyristor direct converters and induction motors (IM). Two types of output filters for restriction of instantaneous torque pulsation are investigated when converters with a small number thyristors realize the combined control of IM. It is shown that these filters can be used as well as reactive power compensators, when IM begins to operate at rated load or at idling. Power factor characteristics have been obtained in the result of computer simulation of 3 kW module operated at the different rotative speeds and thyristor firing angles.

   A Kind of Data Compressing Technology for Reliability Lifetime Test of Relay
By Zhao Xinmin; Zhai Guofu; Gao Yuankai; Liu Maokai; Ping Zhanguo [View]
[Download]

Abstract: A kind of data compresses technology with ERLC (Extended Run Length Coding) method is proposed in this paper. It has been successfully used in the reliability lifetime test of relay which has the features of transient characteristic wave forms and unfixed position in every connecting time period. The hardware design and working process of the data acquisition system are described. The method solved the contradiction between high speed data acquisition and high volume data storage.

   Fuzzy-Neural Network Based Estimation of the Rotor Angular Speed and Parameters of the Induction Motor
By Z. Krzeminski; M. Was [View]
[Download]

Abstract: Estimation of rotor speed and motor parameters is proposed in the paper. The method is based on an effect that variables received from integration of model of induction motor with right sides calculated on a base of variables received from observer have to be equal to variables calculated directly from the observer. If the rotor speed and motor parameters used in the observer and additional model contain errors, the integrated variables differ from the variables calculated from observer variables. The differences are periodically used to correct motor parameters and rotor speed. with application of a neural network The input variables to neural network are fuzzyf~ed. After learning process the rotor speed is estimated almost exactly as can be observed on results of simulation. The same method may be use to estimation of motor parameters.

   Fusion of Low Resolution Encoder and Angular Velocity Estimator in Induction Motor Control
By Janne Davidsainen; Seppo J. 0vaska [View]
[Download]

Abstract: During the last few years, much effort has been put on the development of the sensorless induction motor control. Many sophisticated methods to control the induction motor without an explicit angular velocity feedback have been presented in the literature. Despite of the development of these sensorless control techniques, the angular velocity feedback is still needed with drives requiring precise velocity or torque control in low speeds and standstill. When the electrical velocity of a loaded induction motor is near zero, inaccuracies on motor parameters causes error in flux calculation biasing the response of the sensorless control. This paper presents the results of combining the sensorless control techniques with a low resolution encoder for more precise velocity control. The averaged sensorless velocity estimate and the measured velocity are compared after each encoder pulse registration. The velocity estimate is then corrected by the filtered difference between the estimated and measured velocities. Our straightforward method is tested with a loaded 15 kW induction motor and a low cost encoder giving only 8 or 16 pulses per revolution. The results show that robust control over the whole velocity range is achieved.

   EMC on kW range of Switch Mode Power System
By Matti Hyrkas; Martti Kanervisto [View]
[Download]

Abstract: The electromagnetic compatibility (EMC) has been handled in a product design and study work on kW range of Switch Mode Power System . The experience of standardisation work on EMC has also been described. Results of harmonic interference tests have been analysed.

   The Vector Modulation of a Current Source PWM Rectifier / Inverter
By T. Halkosaari, H. Tuusa [View]
[Download]

Abstract: In this paper four different vector modulation techniques are examined for a current source PWM rectifier (CSR) or a current source PWM inverter (CSI). Different modulation techniques are developed simply by changing the order of adjacent switching space vectors, including the zero space vector, during the switching cycle. Then usually, the switching sequence is held constant through all switching sectors. However, it is possible to reduce switching losses by changing the switching space vector sequence in particular switching sectors, which is finally verified by PSpicem simulations. This paper also shows, by the means of Fourier transformation and frequency convolution that these different modulation techniques own different converter bridge inputloutput AC current and DC-link DC voltage harmonic distortion levels. Furthermore, generalized equations for the CSRICSI AC currents and DC voltage are reviewed.

   Limits for Harmonic Current Emission in EMC-Standards
By Ismo Vainiomai; Jorma Kyyra [View]
[Download]

Abstract: Harmonic current emissions caused by nonlinear loads connected to distribution network have effect to the power quality. These harmonic currents produce harmonic voltages depending on system impedance, and distort the system voltage. In this paper, the some standards for harmonic emissions are particularly handled from the point of view of the switch mode power supplies and the inverter motor drives. Essential content of the standards are represented with a discussion. Also the need for Power Factor Correction (PFC) in various cases is handled.

   Adaptive Current Reference Generator for Active Filters
By Sami Valiviita; Seppo J. Ovaska [View]
[Download]

Abstract: Active power filters are used to eliminate ac harmonic currents by injecting equal but opposite compensating currents. Successful control of active filters requires, among other things, an accurate current reference. In this paper, we introduce a multistage filtering structure which combines a lowpass prefilter and an adaptive predictive filter, making it possible to extract the sinusoidal active current from the distorted waveform without harmful phase shift; even when the frequency and amplitude change. Although active filters are typically used to compensate for the supply harmonics, where the fundamental frequency remains almost constant, we will show that our filter structure can also be applied in applications where the frequency alters rapidly.

   Contactless Measuring of Angular Velocity and Rotary Angle
By Matti Ruusunen; Sami Valiviita; Seppo J. Ovaska [View]
[Download]

Abstract: This paper presents an angular velocity and position measuring system based on surface identities of a rotating object, e.g., a cast traction sheave. The surface of the rotating object is illuminated with LEDs (light emitting diodes), and the reflections are collected to low-cost plastic fibers. The intensity of light is then transformed into voltage signal by photodiodes. Finally, the sampled voltage signal is stored to the memory for use in rotary angle determination task. Also, through the cross-correlation method the angular velocity of the rotating sheave is determined for use in estimating the rotary angle.

   TORQUE BEHAVIOR OF A TWO-PHASE INDUCTION MACHINE WITH NON-0RTHOGON.AL STATOR WINDINGS
By M. Popescu; T. Jokinen [View]
[Download]

Abstract: This paper extent the stationary reference frame [I], to the modeling and analysis of the torque behavior of a two-phase unsymmetrical induction machine with a shifted auxiliary winding. By computer simiulation, compared with experimental results, it is verified the influence of the electrical auxiliary phase stator shift over the machine's torque. The analysis is made for steady-state and transient state operation. The two-phase induction machine (TPIM) is widely used in many light-duty applications were three-phase supply is not readily available. During the development of such a machine, there are several options, including the spatial placement of the auxiliary winding. The torque-slip characteristics can be manipulated by shifting the auxiliary winding from the quadrature position. The analysis of the single-phase or two-phase induction machine with a shifted :auxiliary winding was made by including time domain equivalent circuit [2], symmetrical components [3], or multiple reference frames [4]. The first two methods are acceptable for analyzing the steady-state performance of the machine, while the third method involves too many equations and variables in order to describe the dynamic performance of the TPIM.

   A New Fuzzy Filter with Application in DC Motor Control System
By X. Z. Gao; A. Durnitrescu; V. Burtea; S. J. Ovaska [View]
[Download]

Abstract: In this paper, we propose a new fuzzy filter. Different from the existing fuzzy filters, our model applies the self-organizing map algorithm together with the least squares method to get the optimal membership functions as well as the consequent inference parameters. This approach results in a delayless fuzzy filter that has more efficient filtering capability than the conventional fuzzy filters. A DC servo motor system is employed here as a testbed for this fuzzy filter. Simulation shows that our fuzzy filter is efficiently capable of filtering out the harmful velocity noise produced by the low-cost tachometer in the feedback loop.

   Direct Torque Controlled Inverter in a Robot Positioning Application
By P. Salrninen; A. Rouvinen; J. Pyrhonen [View]
[Download]

Abstract: The original linear manuator shaft positioning system studied consist of a scalar controlled electric drive, whose performance was improved by using different speed references. Methods used for formulating the speed reference were linear PD-control and hyperbolic tangent-control. The other area of interest was to study a direct torque controlled electric drive in the same linear manuator shaft positioning system. The torque reference was calculated from the position error. The properties of the fuzzy control system were compared with the speed controlled positioning system.

   Electrical Characteristics of Electrohydraulic Forming
By L. Laurila [View]
[Download]

Abstract: This article illustrates an unique application of power electronics and high-voltage engineering - electrohydraulic forming, which is a method used for sheet metal forming. The electrical characteristics of electrohydraulic forming are represented. An equivalent circuit of the discharge circuit is represented. Discharge current waveforms estimated with equivalent circuit parameters are compared with measured current waveforms.

   Selection of The Parameters of A Permanent Magnet Synchronous Motor for the Needs of Different Applications
By J. Luukko; M. Seppa [View]
[Download]

Abstract: Selection of the parameters of a permanent magnet synchronous motor is analysed from the viewpoint of different applications. It is shown, that the designer of the motor must be aware of the needs of the particular application. The selection of the motor parameters is presented using theoretical and computational methods. Also some exampies of motor designs are analyzed using FEM.

   DC-voltage Link Converters - Effective Power Supplies for Induction Heating
By P. Silventoinen; J. Nerg; J. Pyrhonen; J. Partanen [View]
[Download]

Abstract: DC-voltage link inverters are effective and flexible power sources for induction heating applications. Different half bridge and full bridge inverter applications are introduced.

NORpie 1998 - Topic 08: POSTERS
You are here: EPE Documents > 05 - EPE Supported Conference Proceedings > NORpie - Proceedings > NORpie 1998 > NORpie 1998 - Topic 08: POSTERS
	[return to parent folder]

	General Purpose Mechatronic Modules on the Base of Direct Converters and Induction Motors By V. I. Chrisanov; YUL N. Konovalov	[View] [Download]
Abstract: The paper presents the results of R&D work on mechatronic modules, consisted of thyristor direct converters and induction motors (IM). Two types of output filters for restriction of instantaneous torque pulsation are investigated when converters with a small number thyristors realize the combined control of IM. It is shown that these filters can be used as well as reactive power compensators, when IM begins to operate at rated load or at idling. Power factor characteristics have been obtained in the result of computer simulation of 3 kW module operated at the different rotative speeds and thyristor firing angles.

	A Kind of Data Compressing Technology for Reliability Lifetime Test of Relay By Zhao Xinmin; Zhai Guofu; Gao Yuankai; Liu Maokai; Ping Zhanguo	[View] [Download]
Abstract: A kind of data compresses technology with ERLC (Extended Run Length Coding) method is proposed in this paper. It has been successfully used in the reliability lifetime test of relay which has the features of transient characteristic wave forms and unfixed position in every connecting time period. The hardware design and working process of the data acquisition system are described. The method solved the contradiction between high speed data acquisition and high volume data storage.

	Fuzzy-Neural Network Based Estimation of the Rotor Angular Speed and Parameters of the Induction Motor By Z. Krzeminski; M. Was	[View] [Download]
Abstract: Estimation of rotor speed and motor parameters is proposed in the paper. The method is based on an effect that variables received from integration of model of induction motor with right sides calculated on a base of variables received from observer have to be equal to variables calculated directly from the observer. If the rotor speed and motor parameters used in the observer and additional model contain errors, the integrated variables differ from the variables calculated from observer variables. The differences are periodically used to correct motor parameters and rotor speed. with application of a neural network The input variables to neural network are fuzzyf~ed. After learning process the rotor speed is estimated almost exactly as can be observed on results of simulation. The same method may be use to estimation of motor parameters.

	Fusion of Low Resolution Encoder and Angular Velocity Estimator in Induction Motor Control By Janne Davidsainen; Seppo J. 0vaska	[View] [Download]
Abstract: During the last few years, much effort has been put on the development of the sensorless induction motor control. Many sophisticated methods to control the induction motor without an explicit angular velocity feedback have been presented in the literature. Despite of the development of these sensorless control techniques, the angular velocity feedback is still needed with drives requiring precise velocity or torque control in low speeds and standstill. When the electrical velocity of a loaded induction motor is near zero, inaccuracies on motor parameters causes error in flux calculation biasing the response of the sensorless control. This paper presents the results of combining the sensorless control techniques with a low resolution encoder for more precise velocity control. The averaged sensorless velocity estimate and the measured velocity are compared after each encoder pulse registration. The velocity estimate is then corrected by the filtered difference between the estimated and measured velocities. Our straightforward method is tested with a loaded 15 kW induction motor and a low cost encoder giving only 8 or 16 pulses per revolution. The results show that robust control over the whole velocity range is achieved.

	EMC on kW range of Switch Mode Power System By Matti Hyrkas; Martti Kanervisto	[View] [Download]
Abstract: The electromagnetic compatibility (EMC) has been handled in a product design and study work on kW range of Switch Mode Power System . The experience of standardisation work on EMC has also been described. Results of harmonic interference tests have been analysed.

	The Vector Modulation of a Current Source PWM Rectifier / Inverter By T. Halkosaari, H. Tuusa	[View] [Download]
Abstract: In this paper four different vector modulation techniques are examined for a current source PWM rectifier (CSR) or a current source PWM inverter (CSI). Different modulation techniques are developed simply by changing the order of adjacent switching space vectors, including the zero space vector, during the switching cycle. Then usually, the switching sequence is held constant through all switching sectors. However, it is possible to reduce switching losses by changing the switching space vector sequence in particular switching sectors, which is finally verified by PSpicem simulations. This paper also shows, by the means of Fourier transformation and frequency convolution that these different modulation techniques own different converter bridge inputloutput AC current and DC-link DC voltage harmonic distortion levels. Furthermore, generalized equations for the CSRICSI AC currents and DC voltage are reviewed.

	Limits for Harmonic Current Emission in EMC-Standards By Ismo Vainiomai; Jorma Kyyra	[View] [Download]
Abstract: Harmonic current emissions caused by nonlinear loads connected to distribution network have effect to the power quality. These harmonic currents produce harmonic voltages depending on system impedance, and distort the system voltage. In this paper, the some standards for harmonic emissions are particularly handled from the point of view of the switch mode power supplies and the inverter motor drives. Essential content of the standards are represented with a discussion. Also the need for Power Factor Correction (PFC) in various cases is handled.

	Adaptive Current Reference Generator for Active Filters By Sami Valiviita; Seppo J. Ovaska	[View] [Download]
Abstract: Active power filters are used to eliminate ac harmonic currents by injecting equal but opposite compensating currents. Successful control of active filters requires, among other things, an accurate current reference. In this paper, we introduce a multistage filtering structure which combines a lowpass prefilter and an adaptive predictive filter, making it possible to extract the sinusoidal active current from the distorted waveform without harmful phase shift; even when the frequency and amplitude change. Although active filters are typically used to compensate for the supply harmonics, where the fundamental frequency remains almost constant, we will show that our filter structure can also be applied in applications where the frequency alters rapidly.

	Contactless Measuring of Angular Velocity and Rotary Angle By Matti Ruusunen; Sami Valiviita; Seppo J. Ovaska	[View] [Download]
Abstract: This paper presents an angular velocity and position measuring system based on surface identities of a rotating object, e.g., a cast traction sheave. The surface of the rotating object is illuminated with LEDs (light emitting diodes), and the reflections are collected to low-cost plastic fibers. The intensity of light is then transformed into voltage signal by photodiodes. Finally, the sampled voltage signal is stored to the memory for use in rotary angle determination task. Also, through the cross-correlation method the angular velocity of the rotating sheave is determined for use in estimating the rotary angle.

	TORQUE BEHAVIOR OF A TWO-PHASE INDUCTION MACHINE WITH NON-0RTHOGON.AL STATOR WINDINGS By M. Popescu; T. Jokinen	[View] [Download]
Abstract: This paper extent the stationary reference frame [I], to the modeling and analysis of the torque behavior of a two-phase unsymmetrical induction machine with a shifted auxiliary winding. By computer simiulation, compared with experimental results, it is verified the influence of the electrical auxiliary phase stator shift over the machine's torque. The analysis is made for steady-state and transient state operation. The two-phase induction machine (TPIM) is widely used in many light-duty applications were three-phase supply is not readily available. During the development of such a machine, there are several options, including the spatial placement of the auxiliary winding. The torque-slip characteristics can be manipulated by shifting the auxiliary winding from the quadrature position. The analysis of the single-phase or two-phase induction machine with a shifted :auxiliary winding was made by including time domain equivalent circuit [2], symmetrical components [3], or multiple reference frames [4]. The first two methods are acceptable for analyzing the steady-state performance of the machine, while the third method involves too many equations and variables in order to describe the dynamic performance of the TPIM.

	A New Fuzzy Filter with Application in DC Motor Control System By X. Z. Gao; A. Durnitrescu; V. Burtea; S. J. Ovaska	[View] [Download]
Abstract: In this paper, we propose a new fuzzy filter. Different from the existing fuzzy filters, our model applies the self-organizing map algorithm together with the least squares method to get the optimal membership functions as well as the consequent inference parameters. This approach results in a delayless fuzzy filter that has more efficient filtering capability than the conventional fuzzy filters. A DC servo motor system is employed here as a testbed for this fuzzy filter. Simulation shows that our fuzzy filter is efficiently capable of filtering out the harmful velocity noise produced by the low-cost tachometer in the feedback loop.

	Direct Torque Controlled Inverter in a Robot Positioning Application By P. Salrninen; A. Rouvinen; J. Pyrhonen	[View] [Download]
Abstract: The original linear manuator shaft positioning system studied consist of a scalar controlled electric drive, whose performance was improved by using different speed references. Methods used for formulating the speed reference were linear PD-control and hyperbolic tangent-control. The other area of interest was to study a direct torque controlled electric drive in the same linear manuator shaft positioning system. The torque reference was calculated from the position error. The properties of the fuzzy control system were compared with the speed controlled positioning system.

	Electrical Characteristics of Electrohydraulic Forming By L. Laurila	[View] [Download]
Abstract: This article illustrates an unique application of power electronics and high-voltage engineering - electrohydraulic forming, which is a method used for sheet metal forming. The electrical characteristics of electrohydraulic forming are represented. An equivalent circuit of the discharge circuit is represented. Discharge current waveforms estimated with equivalent circuit parameters are compared with measured current waveforms.

	Selection of The Parameters of A Permanent Magnet Synchronous Motor for the Needs of Different Applications By J. Luukko; M. Seppa	[View] [Download]
Abstract: Selection of the parameters of a permanent magnet synchronous motor is analysed from the viewpoint of different applications. It is shown, that the designer of the motor must be aware of the needs of the particular application. The selection of the motor parameters is presented using theoretical and computational methods. Also some exampies of motor designs are analyzed using FEM.

	DC-voltage Link Converters - Effective Power Supplies for Induction Heating By P. Silventoinen; J. Nerg; J. Pyrhonen; J. Partanen	[View] [Download]
Abstract: DC-voltage link inverters are effective and flexible power sources for induction heating applications. Different half bridge and full bridge inverter applications are introduced.