EPE Association: EPE 2007 - Subtopic 12-4 - DS: High performance drives

EPE 2007 - Subtopic 12-4 - DS: High performance drives
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2007 - Conference > EPE 2007 - Topic 12: 'High performance drives' > EPE 2007 - Subtopic 12-4 - DS: High performance drives

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   A FPGA Based New Space Voltage Vector Modulation Inverter Considering Voltage Saturation for Speed Servo System of Induction Motor
By TAKAHASHI Kenji; OHISHI Kiyoshi; KANMACHI Toshiyuki [View]
[Download]

Abstract: This paper proposes a new switching control method of space voltage vector modulation inverter for speed servo system of induction motor. The proposed method shortens the digital control time of space voltage vector modulation inverter and improves the current control performance with wide bandwidth. Moreover, the proposed switching method is implemented by using FPGA in order to enhance its control performance. In addition, by using PI controllers considering voltage saturation, the speed servo system has more stable speed control characteristics. The effectiveness of proposed control method is verified by the experimental results.

   A simple parameter estimation method for vector control of an induction motor
By SUL Seung-Ki; SHIM Young-Seok; YOON Young-Doo; CHOI Yoon-Young; LEE Wook-Jin [View]
[Download]

Abstract: This paper presents a simple self-commissioning algorithm to estimate various motor parameters for Rotor-Flux-Oriented (RFO) induction motor drive. As the parameters are calculated from simple voltage equations and integration, it is possible for the proposed algorithm to be included in the main program with a low cost micro-controller. Also, it works well under arbitrary operating condition, and it is robust to measurement noise.

   Analysis of Frame Alignment Issues in Natural Field Orientation Including Non-Linear and Leakage Inductance Effects
By MIRZAEVA Galina; BETZ Robert [View]
[Download]

Abstract: The Natural Field Orientation (NFO) algorithm is a form of Stator Flux Orientation (SFO) that has the desirable property that it does not use integration to determine the position of the stator flux reference frame. It is also supposed to implicitly correct reference frame errors. However, under certain modes of operation this does not occur. The purpose of this paper is to develop non-linear analytical expressions that accurately model this problem and then verify them against simulation and experimental results. This objective is achieved by using two non-linear modelling approaches -- a simplified one which assumes that the machine has no leakage, and one where leakage is considered. The accuracy of two approaches are compared with each other. Furthermore, a solution to the frame instability is also proposed and analysed. The analytical results are verified by simulation and experiment.

   Analytical model describing the operation behaviour of Transverse Flux Machines in flat magnet configuration
By SCHUETTLER Jochen; ORLIK Bernd [View]
[Download]

Abstract: This paper presents an analytical model of the electromechanical behaviour of transverse flux machines in flat magnet configuration. The model is based on the distribution of the magnetic field inside the machine, which will be given special focus, due to its significance in calculating the electric torque by means of the magnetic coenergy.

   Comparative Study of IPMSM Control Strategies for Torque Ripple Reduction
By INOUE Yukinori; MORIMOTO Shigeo; SANADA Masayuki [View]
[Download]

Abstract: This paper compares the effectiveness of two control strategies for torque ripple reduction of interior permanent magnet synchronous motors with harmonics in both magnet flux and inductance. One strategy is current control and the other is direct torque control. For current control, two estimation methods for the instantaneous torque are introduced; a parameter-based equation in the rotating frame and a flux-based calculation in the stationary frame. The effectiveness of these schemes is examined. From simulation results, the characteristics of instantaneous torque for direct torque control and current control are discussed.

   Direct Torque Control for Interior Permanent Magnet Synchronous Motors with Respect to Optimal Efficiency
By MEYER Michael; BÃ–CKER Joachim; GROTE Tobias [View]
[Download]

Abstract: Due to their high torque and power per volume ratio, interior permanent magnet synchronous motors (IPMSM) are widespread electrical machines for traction drive applications, e.g. in the drive train of hybrid electric vehicles (HEV). IPMSM exhibit a significant degree of saliency along the rotor circumference. Thus, in order to exploit the full potential of an IPMSM drive, it is mandatory to utilize the reluctance torque. As a result, using a rotor flux oriented torque control, the clear separation between flux and torque generating currents is no longer possible, i.e. that the determination of the reference currents for the subordinated current control is rather difficult. Furthermore, drive applications demand for a wide constant power range with flux weakening ratios of up to 1:5 or even higher. However, flux weakening operation demands for additional measures to ensure that the current controllers dispose of a minimum amount of voltage reserve, which is necessary to govern transients and to compensate for disturbances. In this contribution a Direct Torque Control (DTC) structure is proposed to cope with the afore mentioned problems. In a DTC structure, torque and flux are controlled directly. Hence, the approach is very well suited for operation at saturated voltage. Furthermore, with torque and flux as control variables, it is not necessary to determine any reference currents. However, the proposed structure utilizes two Look Up Tables (LUT) for the determination of efficiency-optimal set values for flux and torque. The LUT are generated based on measurement results. So, they do already account for saturation effects. The proposed DTC structure has been implemented and verified on a test bed.

   Direct Torque Control using Space Vector Modulation and dynamic performance of the drive, via a Fuzzy Logic controller for speed regulation
By KOUTSOGIANNIS Z.; ADAMIDIS Georgios; FYNTANAKIS A. [View]
[Download]

Abstract: This paper presents a method of controlling the Torque of an asynchronous motor that is fed by a PWM-Inverter. The control method that is used is a modified Direct Torque Control (DTC) scheme with constant switching frequency, using Space Vector Modulation (SVM). In this scheme a closed loop of torque control is applied. Small and rapid changes on motor's torque are achieved by applying an appropriate voltage vector, which is responsible for the jerky movement of the stator's flux vector. The voltage vector can be of any magnitude and angle and is produced using Space Vector Pulse Width Modulation. The modified method of DTC using SVM improves the electrical magnitudes of asynchronous machine, such as reduction of current and flux ripple and also fading out the edges of torque ripple which are occurred during the sector changes of stator flux vector. Another point of this paper is the presentation of speed control in dynamic situations. The production of the reference torque value is achieved by using a fuzzy logic speed controller. The response of the fuzzy PI is compared to the response of a classic PI speed controller. Results, shows that the fuzzy PI speed controller has a better response in a wide range area of motor speed. Combining the characteristics of DTC-SVM scheme and the fuzzy logic speed controller we can have a high performance vector controlled asynchronous motor drive.

   General Aspects of the Electrical Drive Systems Optimal Control
By BOTAN Corneliu; HORGA Vasile; OSTAFI Florin; RATOI Marcel; ALBU Mihai [View]
[Download]

Abstract: The optimal control of the transient state of the electrical drive systems with DC and AC motors is presented. Similar interesting results for different motor types are obtained. A simple implementable suboptimal solution is proposed.

   Implementation of Dynamically Reconfigurable Control Structures on a Single FPGA Platform
By MATHAPATI Shashidhar; BÃ–CKER Joachim [View]
[Download]

Abstract: More than one control schemes for the motor control with the dynamic change-over between them is termed as "dynamically reconfigurable control structures". Such a dynamically reconfigurable control structure for induction machine is proposed and implemented on a single FPGA platform. The inherent feature of FPGA i.e. the parallel execution offers ease and more enabling to implement such a multiple control structure. The content of paper emphasises on the basic arrangement of concept, implementation, sharing the common modules between the control schemes and the space characterization on FPGA.

   IMROVED VECTOR CONTROL OF INDUCTION MOTOR DRIVE USING GENETIC ALGORITHMS-BASE MACHINE AND CONTROL PARAMETERS ESTIMATION
By ZANCHETTA Pericle; WHEELER Patrick; CLARE Jon; TRENTIN Andrew [View]
[Download]

Abstract: This paper presents an improved rotor flux-based vector control for a high power induction machine. An off-line Genetic Algorithms routine is used to estimate the electrical and mechanical parameters of the machine using only speed transient measurements. This routine is used for a range of operating conditions for the control algorithm and design optimisation. The effectiveness of this design method is demonstrated with a wide range of simulations and experimental results at power levels up to 200kW.

   Influence of voltage vectors of a NPC inverter on torque and flux variations of a DTC drive considering different load and speed conditions
By RADAN Ahmad; GHARAKHANI Arbi [View]
[Download]

Abstract: Direct Torque Control (DTC) is one of the most effective vector control methods proposed for high performance drives of a wide variety of industrial applications. This control method becomes more attractive when applied on the Neutral Point Clamped (NPC) Inverter driven drives. While exploring accurate analytical equations of torque and flux variations, this paper investigates analytically the affecting characteristic of voltage vectors of a NPC converter on variations of stator flux and electromagnetic torque (decreasing or increasing) of medium voltage induction motor drives. The analytically obtained results show that the affecting characteristic of some voltage vectors depends not only on the flux sector in which the stator flux vector is located but also on the exact position of flux vector inside that sector. Besides the load and speed conditions of a machine can change the affecting characteristic of voltage vectors undesirably. The paper studies application of DTC method in NPC inverter driven induction motors and considers different load and speed conditions. It proposes a set of appropriate voltage vectors for accurate control of torque and flux variations considering degrees of freedom in voltage vector selection provided by NPC Inverter.

   Modelling of Quantization Effects in Current Control for a Synchronous Servo Drive
By GRÃ–LING Christian; SCHUMACHER Walter; AMLANG Bernd [View]
[Download]

Abstract: One major problem during development of a current control for a synchronous servo drive is to estimate the resulting torque ripple, which is generated by quantization and noise. Due to the non-linear character of quantizers, control engineers tend to minimize torque ripple caused by electronic components, a/d converters and sampling techniques experimentally by designing a prototype, thus generating avoidable costs. This paper proposes a technique based on stochastical linearization, which provides a simple linear model of a quantized current control loop. With aid of the linear model, the influence of quantization and noise on motor torque can be calculated. Thereby limits for current- and voltage resolutions are derived, which lead to non-linear system behaviour when neglected. Lastly, the results obtained are verified experimentally.

   MRAS Speed sensorless vector control of Induction Machine with saturation and Iron Loss Effects compensation
By TOUHAMI Omar; MOULAHOUM Samir [View]
[Download]

Abstract: The abstract is not available.

   Nonlinear Dynamics in Direct Torque Controlled Induction Machines Analyzed by Recurrence Plots
By SÃœTŐ ZoltÃ¡n; MASADA Eisuke; NAGY IstvÃ¡n [View]
[Download]

Abstract: The source of nonlinearity are the hysteresis comparators and dependence of switchings on state variables in Direct Torque Controlled (DTC) Induction Machines (IM). The nonlinearity generates some strange operation states. They are revealed, analyzed by bifurcation diagram and recurrence plots both in motoring and generating operations.

   Position control of a Transverse Flux Motor with reduced torque ripples for Direct Servo-Drive Applications using shaped currents with harmonics control
By WERNER Uwe; SCHÃœTTLER Jochen; ORLIK Bernd [View]
[Download]

Abstract: This paper presents a control based upon optimised current waveforms with switching on current harmonics to achieve an accurate position and speed control with reduced ripples in torque shape for a transverse flux motor. The approaches are verified by measured results at a two phase prototype of a magnet exicited transverse flux motor.

   Robust DTC-SVM Method for Matrix Converter Drives with Model Reference Adaptive Control Scheme
By LEE Kyo-Beum; HUH Sunghoi; SIM Kyung-Hun; BLAABJERG Frede [View]
[Download]

Abstract: This paper presents a new robust DTC-SVM control system for high performance induction motor drives fed by a matrix converter with variable structure - model reference adaptive control scheme (VS-MRAC). It is possible to combine the advantages of matrix converters with the advantages of the DTC strategy using space vector modulations and a deadbeat algorithm in the stator flux reference frame. The lumped disturbances such as parameter variation and load disturbance of the system are estimated by a neuro-sliding mode approach based on model reference adaptive control (MRAC). An adaptive observer is also employed to bring better responses at the low speed operation. Simulation results are shown to illustrate the performance of the proposed system.

   Run-Time Reconfiguration of FPGA-Based Drive Controllers
By PORRMANN Mario; SCHULZ Bernd; PAIZ Carlos; MATHAPATI Shashidhar ; BOECKER Joachim [View]
[Download]

Abstract: In this contribution a Field Programmable Gate Array (FPGA) is used as target architecture to implement drive controllers. A novel concept for generic run-time switching between FPGA-based drive controllers is presented. The controller switching is done by using partial run-time hardware reconfiguration, which allows the implementation of various controllers without having to realize them all on the FPGA concurrently. It is shown that time-sharing of the FPGA resources can provide a resource-efficient implementation. A system architecture, which enables the realization of this scheme, is presented. A hard switching between controllers is implemented, for which the initial internal states of the controller to-be-loaded are computed. Experimental results show that the proposed scheme works satisfactory, opening new possibilities to the implementation of such adaptive control schemes.

   Stability Analysis of the Instantaneous Power Control (IPC) Algorithm for Induction Machines.
By BETZ Robert; SUMMERS Terry [View]
[Download]

Abstract: Instantaneous Power Control (IPC) has over recent years been proposed as an alternative method for the control of induction machines. This paper provides a stability analysis of the algorithm using linear techniques. Results are presented which confirm that the algorithm, in its raw form, does have a stability problem in regeneration. However the presence of a PLL based filter on the back-emf estimates, which is essential for practical implementation, stabilises the algorithm.

   Torque Ripple Reduction in PMSM DTC Drives using Matrix Converters
By ORTEGA Carlos; ARIAS Antoni; BALCELLS Josep; CARUANA Cedric ; APAP Maurice [View]
[Download]

Abstract: The paper investigates the use of the small voltage vectors of Matrix Converters (MC) in order to reduce the inherent torque ripple that appears when Direct Torque Control (DTC) is used to control Permanent Magnets Synchronous Motors (PMSM). The new approach will differentiate between small and large torque errors, thus reducing the electromagnetic torque ripple. A comparison between the classical Direct Torque Control using Matrix Converters and the proposed method is carried out. Results which demonstrate the improvement of the novel Direct Torque Control are shown.

EPE 2007 - Subtopic 12-4 - DS: High performance drives
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2007 - Conference > EPE 2007 - Topic 12: 'High performance drives' > EPE 2007 - Subtopic 12-4 - DS: High performance drives
	[return to parent folder]

	A FPGA Based New Space Voltage Vector Modulation Inverter Considering Voltage Saturation for Speed Servo System of Induction Motor By TAKAHASHI Kenji; OHISHI Kiyoshi; KANMACHI Toshiyuki	[View] [Download]
Abstract: This paper proposes a new switching control method of space voltage vector modulation inverter for speed servo system of induction motor. The proposed method shortens the digital control time of space voltage vector modulation inverter and improves the current control performance with wide bandwidth. Moreover, the proposed switching method is implemented by using FPGA in order to enhance its control performance. In addition, by using PI controllers considering voltage saturation, the speed servo system has more stable speed control characteristics. The effectiveness of proposed control method is verified by the experimental results.

	A simple parameter estimation method for vector control of an induction motor By SUL Seung-Ki; SHIM Young-Seok; YOON Young-Doo; CHOI Yoon-Young; LEE Wook-Jin	[View] [Download]
Abstract: This paper presents a simple self-commissioning algorithm to estimate various motor parameters for Rotor-Flux-Oriented (RFO) induction motor drive. As the parameters are calculated from simple voltage equations and integration, it is possible for the proposed algorithm to be included in the main program with a low cost micro-controller. Also, it works well under arbitrary operating condition, and it is robust to measurement noise.

	Analysis of Frame Alignment Issues in Natural Field Orientation Including Non-Linear and Leakage Inductance Effects By MIRZAEVA Galina; BETZ Robert	[View] [Download]
Abstract: The Natural Field Orientation (NFO) algorithm is a form of Stator Flux Orientation (SFO) that has the desirable property that it does not use integration to determine the position of the stator flux reference frame. It is also supposed to implicitly correct reference frame errors. However, under certain modes of operation this does not occur. The purpose of this paper is to develop non-linear analytical expressions that accurately model this problem and then verify them against simulation and experimental results. This objective is achieved by using two non-linear modelling approaches -- a simplified one which assumes that the machine has no leakage, and one where leakage is considered. The accuracy of two approaches are compared with each other. Furthermore, a solution to the frame instability is also proposed and analysed. The analytical results are verified by simulation and experiment.

	Analytical model describing the operation behaviour of Transverse Flux Machines in flat magnet configuration By SCHUETTLER Jochen; ORLIK Bernd	[View] [Download]
Abstract: This paper presents an analytical model of the electromechanical behaviour of transverse flux machines in flat magnet configuration. The model is based on the distribution of the magnetic field inside the machine, which will be given special focus, due to its significance in calculating the electric torque by means of the magnetic coenergy.

	Comparative Study of IPMSM Control Strategies for Torque Ripple Reduction By INOUE Yukinori; MORIMOTO Shigeo; SANADA Masayuki	[View] [Download]
Abstract: This paper compares the effectiveness of two control strategies for torque ripple reduction of interior permanent magnet synchronous motors with harmonics in both magnet flux and inductance. One strategy is current control and the other is direct torque control. For current control, two estimation methods for the instantaneous torque are introduced; a parameter-based equation in the rotating frame and a flux-based calculation in the stationary frame. The effectiveness of these schemes is examined. From simulation results, the characteristics of instantaneous torque for direct torque control and current control are discussed.

	Direct Torque Control for Interior Permanent Magnet Synchronous Motors with Respect to Optimal Efficiency By MEYER Michael; BÃ–CKER Joachim; GROTE Tobias	[View] [Download]
Abstract: Due to their high torque and power per volume ratio, interior permanent magnet synchronous motors (IPMSM) are widespread electrical machines for traction drive applications, e.g. in the drive train of hybrid electric vehicles (HEV). IPMSM exhibit a significant degree of saliency along the rotor circumference. Thus, in order to exploit the full potential of an IPMSM drive, it is mandatory to utilize the reluctance torque. As a result, using a rotor flux oriented torque control, the clear separation between flux and torque generating currents is no longer possible, i.e. that the determination of the reference currents for the subordinated current control is rather difficult. Furthermore, drive applications demand for a wide constant power range with flux weakening ratios of up to 1:5 or even higher. However, flux weakening operation demands for additional measures to ensure that the current controllers dispose of a minimum amount of voltage reserve, which is necessary to govern transients and to compensate for disturbances. In this contribution a Direct Torque Control (DTC) structure is proposed to cope with the afore mentioned problems. In a DTC structure, torque and flux are controlled directly. Hence, the approach is very well suited for operation at saturated voltage. Furthermore, with torque and flux as control variables, it is not necessary to determine any reference currents. However, the proposed structure utilizes two Look Up Tables (LUT) for the determination of efficiency-optimal set values for flux and torque. The LUT are generated based on measurement results. So, they do already account for saturation effects. The proposed DTC structure has been implemented and verified on a test bed.

	Direct Torque Control using Space Vector Modulation and dynamic performance of the drive, via a Fuzzy Logic controller for speed regulation By KOUTSOGIANNIS Z.; ADAMIDIS Georgios; FYNTANAKIS A.	[View] [Download]
Abstract: This paper presents a method of controlling the Torque of an asynchronous motor that is fed by a PWM-Inverter. The control method that is used is a modified Direct Torque Control (DTC) scheme with constant switching frequency, using Space Vector Modulation (SVM). In this scheme a closed loop of torque control is applied. Small and rapid changes on motor's torque are achieved by applying an appropriate voltage vector, which is responsible for the jerky movement of the stator's flux vector. The voltage vector can be of any magnitude and angle and is produced using Space Vector Pulse Width Modulation. The modified method of DTC using SVM improves the electrical magnitudes of asynchronous machine, such as reduction of current and flux ripple and also fading out the edges of torque ripple which are occurred during the sector changes of stator flux vector. Another point of this paper is the presentation of speed control in dynamic situations. The production of the reference torque value is achieved by using a fuzzy logic speed controller. The response of the fuzzy PI is compared to the response of a classic PI speed controller. Results, shows that the fuzzy PI speed controller has a better response in a wide range area of motor speed. Combining the characteristics of DTC-SVM scheme and the fuzzy logic speed controller we can have a high performance vector controlled asynchronous motor drive.

	General Aspects of the Electrical Drive Systems Optimal Control By BOTAN Corneliu; HORGA Vasile; OSTAFI Florin; RATOI Marcel; ALBU Mihai	[View] [Download]
Abstract: The optimal control of the transient state of the electrical drive systems with DC and AC motors is presented. Similar interesting results for different motor types are obtained. A simple implementable suboptimal solution is proposed.

	Implementation of Dynamically Reconfigurable Control Structures on a Single FPGA Platform By MATHAPATI Shashidhar; BÃ–CKER Joachim	[View] [Download]
Abstract: More than one control schemes for the motor control with the dynamic change-over between them is termed as "dynamically reconfigurable control structures". Such a dynamically reconfigurable control structure for induction machine is proposed and implemented on a single FPGA platform. The inherent feature of FPGA i.e. the parallel execution offers ease and more enabling to implement such a multiple control structure. The content of paper emphasises on the basic arrangement of concept, implementation, sharing the common modules between the control schemes and the space characterization on FPGA.

	IMROVED VECTOR CONTROL OF INDUCTION MOTOR DRIVE USING GENETIC ALGORITHMS-BASE MACHINE AND CONTROL PARAMETERS ESTIMATION By ZANCHETTA Pericle; WHEELER Patrick; CLARE Jon; TRENTIN Andrew	[View] [Download]
Abstract: This paper presents an improved rotor flux-based vector control for a high power induction machine. An off-line Genetic Algorithms routine is used to estimate the electrical and mechanical parameters of the machine using only speed transient measurements. This routine is used for a range of operating conditions for the control algorithm and design optimisation. The effectiveness of this design method is demonstrated with a wide range of simulations and experimental results at power levels up to 200kW.

	Influence of voltage vectors of a NPC inverter on torque and flux variations of a DTC drive considering different load and speed conditions By RADAN Ahmad; GHARAKHANI Arbi	[View] [Download]
Abstract: Direct Torque Control (DTC) is one of the most effective vector control methods proposed for high performance drives of a wide variety of industrial applications. This control method becomes more attractive when applied on the Neutral Point Clamped (NPC) Inverter driven drives. While exploring accurate analytical equations of torque and flux variations, this paper investigates analytically the affecting characteristic of voltage vectors of a NPC converter on variations of stator flux and electromagnetic torque (decreasing or increasing) of medium voltage induction motor drives. The analytically obtained results show that the affecting characteristic of some voltage vectors depends not only on the flux sector in which the stator flux vector is located but also on the exact position of flux vector inside that sector. Besides the load and speed conditions of a machine can change the affecting characteristic of voltage vectors undesirably. The paper studies application of DTC method in NPC inverter driven induction motors and considers different load and speed conditions. It proposes a set of appropriate voltage vectors for accurate control of torque and flux variations considering degrees of freedom in voltage vector selection provided by NPC Inverter.

	Modelling of Quantization Effects in Current Control for a Synchronous Servo Drive By GRÃ–LING Christian; SCHUMACHER Walter; AMLANG Bernd	[View] [Download]
Abstract: One major problem during development of a current control for a synchronous servo drive is to estimate the resulting torque ripple, which is generated by quantization and noise. Due to the non-linear character of quantizers, control engineers tend to minimize torque ripple caused by electronic components, a/d converters and sampling techniques experimentally by designing a prototype, thus generating avoidable costs. This paper proposes a technique based on stochastical linearization, which provides a simple linear model of a quantized current control loop. With aid of the linear model, the influence of quantization and noise on motor torque can be calculated. Thereby limits for current- and voltage resolutions are derived, which lead to non-linear system behaviour when neglected. Lastly, the results obtained are verified experimentally.

	MRAS Speed sensorless vector control of Induction Machine with saturation and Iron Loss Effects compensation By TOUHAMI Omar; MOULAHOUM Samir	[View] [Download]
Abstract: The abstract is not available.

	Nonlinear Dynamics in Direct Torque Controlled Induction Machines Analyzed by Recurrence Plots By SÃœTŐ ZoltÃ¡n; MASADA Eisuke; NAGY IstvÃ¡n	[View] [Download]
Abstract: The source of nonlinearity are the hysteresis comparators and dependence of switchings on state variables in Direct Torque Controlled (DTC) Induction Machines (IM). The nonlinearity generates some strange operation states. They are revealed, analyzed by bifurcation diagram and recurrence plots both in motoring and generating operations.

	Position control of a Transverse Flux Motor with reduced torque ripples for Direct Servo-Drive Applications using shaped currents with harmonics control By WERNER Uwe; SCHÃœTTLER Jochen; ORLIK Bernd	[View] [Download]
Abstract: This paper presents a control based upon optimised current waveforms with switching on current harmonics to achieve an accurate position and speed control with reduced ripples in torque shape for a transverse flux motor. The approaches are verified by measured results at a two phase prototype of a magnet exicited transverse flux motor.

	Robust DTC-SVM Method for Matrix Converter Drives with Model Reference Adaptive Control Scheme By LEE Kyo-Beum; HUH Sunghoi; SIM Kyung-Hun; BLAABJERG Frede	[View] [Download]
Abstract: This paper presents a new robust DTC-SVM control system for high performance induction motor drives fed by a matrix converter with variable structure - model reference adaptive control scheme (VS-MRAC). It is possible to combine the advantages of matrix converters with the advantages of the DTC strategy using space vector modulations and a deadbeat algorithm in the stator flux reference frame. The lumped disturbances such as parameter variation and load disturbance of the system are estimated by a neuro-sliding mode approach based on model reference adaptive control (MRAC). An adaptive observer is also employed to bring better responses at the low speed operation. Simulation results are shown to illustrate the performance of the proposed system.

	Run-Time Reconfiguration of FPGA-Based Drive Controllers By PORRMANN Mario; SCHULZ Bernd; PAIZ Carlos; MATHAPATI Shashidhar ; BOECKER Joachim	[View] [Download]
Abstract: In this contribution a Field Programmable Gate Array (FPGA) is used as target architecture to implement drive controllers. A novel concept for generic run-time switching between FPGA-based drive controllers is presented. The controller switching is done by using partial run-time hardware reconfiguration, which allows the implementation of various controllers without having to realize them all on the FPGA concurrently. It is shown that time-sharing of the FPGA resources can provide a resource-efficient implementation. A system architecture, which enables the realization of this scheme, is presented. A hard switching between controllers is implemented, for which the initial internal states of the controller to-be-loaded are computed. Experimental results show that the proposed scheme works satisfactory, opening new possibilities to the implementation of such adaptive control schemes.

	Stability Analysis of the Instantaneous Power Control (IPC) Algorithm for Induction Machines. By BETZ Robert; SUMMERS Terry	[View] [Download]
Abstract: Instantaneous Power Control (IPC) has over recent years been proposed as an alternative method for the control of induction machines. This paper provides a stability analysis of the algorithm using linear techniques. Results are presented which confirm that the algorithm, in its raw form, does have a stability problem in regeneration. However the presence of a PLL based filter on the back-emf estimates, which is essential for practical implementation, stabilises the algorithm.

	Torque Ripple Reduction in PMSM DTC Drives using Matrix Converters By ORTEGA Carlos; ARIAS Antoni; BALCELLS Josep; CARUANA Cedric ; APAP Maurice	[View] [Download]
Abstract: The paper investigates the use of the small voltage vectors of Matrix Converters (MC) in order to reduce the inherent torque ripple that appears when Direct Torque Control (DTC) is used to control Permanent Magnets Synchronous Motors (PMSM). The new approach will differentiate between small and large torque errors, thus reducing the electromagnetic torque ripple. A comparison between the classical Direct Torque Control using Matrix Converters and the proposed method is carried out. Results which demonstrate the improvement of the novel Direct Torque Control are shown.