EPE Association: EPE 2009 - Subtopic 05-5

EPE 2009 - Subtopic 05-5 - DS: 'Matrix Converters'
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2009 - Conference > EPE 2009 - Topic 05: 'Hard Switching Converters and Control' > EPE 2009 - Subtopic 05-5 - DS: 'Matrix Converters'

   [return to parent folder]

   A Modified Carrier-Based Modulation Method for Three-Phase Matrix Converters
By Panagiotis POTAMIANOS, Epaminondas MITRONIKAS, Athanasios SAFACAS [View]
[Download]

Abstract: A modified carrier-based modulation method for three-phase matrix converters is proposed. This method enhances the MC performance comparing to the â€œconventionalâ€ carrier-based modulation methods in regard to the switching losses and the output voltage harmonic distortion. The output current waveform is also improved in the case of the proposed modulation method with 8 commutations per switching period (TSW), but it is deteriorated in the case of 12 commutations per TSW. Due to the fact that the proposed method is applicable when that the desired voltage transfer ratio is less than 50\%, the control algorithm also adapts a carrier-based modulation method for the cases of voltage transfer ratio larger than 50\%, which is also used for comparison and evaluation of the proposed method.

   An experimental study on induction motor drive with a single phase - three phasematrix converter
By Kazuyuki IINO, Keiichiro KONDO, Yukihiko SATO [View]
[Download]

Abstract: This paper deals with a control method and a designing method of the capacitance of the compensation capacitor for a single phase to three phase matrix converters (MCs) with the variable speed drive capability of induction motors (IMs). Assuming the application of railway tractions, automobiles and elevators, motors drive inertial load. In such cases, both the load power and the load voltage increase in proportion to the rotor speed. The amplitude of the compensation capacitor voltage is controlled to absorb the single phase power fluctuation, along with the load power. We propose a method to decide the input side parameters such as the capacitance of the compensation capacitor, considering the input voltage and the power of the IM. We experimentally verify that a single phase to three phase MC can drive IMs with the proposed method.

   Comparison between back-to-back and matrix converter drives under faulty conditions
By SÃ©rgio CRUZ, Marco FERREIRA [View]
[Download]

Abstract: This paper presents a comparison study between the operation of a back-to-back and a matrix converter induction motor drive under the presence of faults in the power switches of these converters. These two topologies are functionally equivalent in terms of input power quality and energy regeneration capabilities but need to be compared in terms of performance under faulty conditions as well due to the high number of switches involved in these two converters. In particular, the total waveform distortion of the input/output currents of the two converters and the motor torque oscillations were measured with the aim to determine which converter performs better under faulty conditions. Based on simulation results obtained with a detailed model of the two drive systems, it is shown that the distortions of the input/output currents caused by a single-fault in a matrix converter are approximately identical to the ones that appear in a back-to-back converter with two faults, one in the rectifier stage and the other one in the inverter stage. On the other hand, the back-to-back converter is perfectly capable of operating with an open-circuit fault provided that it is located in the rectifier stage, being the operation of the motor practically unaffected in that case. In general terms it can be said that due to the absence of an energy storage element, the matrix converter is particular sensitive to the appearance of faults. The back-to-back converter, on the other hand, is capable of maintaining a better quality of operation of the motor under faulty conditions, provided that the faults are not located in the inverter stage.

   Comparison of Three Switching Strategies for Indirect Matrix Converter
By Alireza JAHANGIRI, Ahmad RADAN, Mehdi HAGHSHENAS [View]
[Download]

Abstract: The Indirect Matrix Converter (IMC) concept has been gaining recognition as a promising circuit alternative in recent years. An IMC has separate line and load side converters. Each switching period of line side converter is split into two portions. In each portion, the IMC is equivalent to a conventional inverter. Thus, output voltage can be obtained through applying a kind of space vector PWM to the load side converter. Conventional space vector pulsewidth modulation (CSVPWM) employs conventional switching sequence, which divides the zero vector time equally between two zero states in each modulation cycle. If a double edge CSVPWM used in each portion, each switch of the load side converter would have a switching frequency twice the sampling frequency. Therefore, bus-clamping PWM (BCPWM) techniques which use only one zero state in each modulation cycle can be used to reduce the switching frequency. This paper comprises two types of BCPWM techniques and a new special type of switching sequences, termed here as â€œsawthooth sequencesâ€. The proposed technique: 1) reduces the load side converter switching frequency and losses; 2) has good performance in viewpoint of input/output waveform quality 3) has switching losses independent of output power factor. Simulation results are presented to demonstrate the validity of the proposed space vector modulation technique.

   Control Strategy of an Indirect Matrix Converter with Modifying DC voltage
By ruben PENA, roberto CARDENAS, eduardo REYES, pat WHEELER, jon CLARE [View]
[Download]

Abstract: The Indirect Matrix Converter (IMC) consists of an input matrix converter stage and an output voltage source inverter (VSI) stage. The input matrix converter provides the DC voltage needed for the output stage. Usually, the switching sequences of the input and output stages are arranged to have soft switching commutation at the input stage. The capability of the input matrix converter to generate produce different DC voltages is exploited in this paper. If the converter can operate at a reduced DC voltage then commutation of the VSI can take place at lower voltages. Depending on the required output voltage, the modulation of the input matrix converter is changed in order to obtain a lower/higher DC voltage without causing over modulation The strategy could be applied to a cage induction machine drive, operating at low speed and therefore requiring low voltage, or a doubly-fed induction machine drive operating near synchronous speed where the required rotor voltage is smaller. The strategy is experimentally validated controlling the output current of the IMC feeding a resistive-inductive load. Experimental results are shown for step changes in demanded reference currents and current regulation at different modulation strategies of the input converter.

   Diagnosis of open-circuit faults in matrix converters
By SÃ©rgio CRUZ, Marco FERREIRA, AntÃ³nio CARDOSO [View]
[Download]

Abstract: This paper presents a new diagnostic technique, known as the Modulated Error Voltages (MEV), for the diagnosis of open-circuits faults in the power switches of matrix converters. The proposed technique is based on the monitoring of nine modulated output error voltages, each one associated to a bidirectional switch of the converter. For each output phase, an error voltage is calculated and subsequently modulated by the gate signals of each one of the three bidirectional switches connected to that specific phase. Each modulated signal is subsequently averaged over a certain period of time. If at the end of this averaging period the obtained value is higher than a threshold limit, it will trigger the indication of an open-circuit fault in the power switch associated to the monitored signal. By using the MEV it is possible to concurrently detect and locate open-circuit faults, independently of the type of load of the matrix converter or its operating conditions, namely amplitude and frequency of the output voltages, both in steady-state and transient regimes. Moreover, the MEV allows to speed up the diagnostic process when compared to other diagnostic techniques, and can easily deal with the presence of multiple faults occurring simultaneously.

   Improvement of Output Voltage Waveform for ARCP Matrix Converter
By Takanori HATASE, Takashi ABE, Tsuyoshi HIGUCHI, Hidenori HARA [View]
[Download]

Abstract: A Matrix Converter (MC) is an AC-to-AC conversion device that can generate variable magnitude and frequency output voltage. The higher carrier frequency is selected for more accurate and low acoustic noise. However, using a high carrier frequency causes new problems, such as the increase of switching loss and premature breakdown of power device. Therefore, the auxiliary resonant commutated pole (ARCP) is applied to a MC and ARCPMC has been proposed. This paper shows how the method intended for improvement of the output voltage waveform for ARCPMC was verified using the system simulation and confirmed through experimental results.

   NEW CONTROL ALGORITHM FOR TRACTION DRIVE WITH SINGLE PHASE MATRIX CONVERTER
By Pavel DRABEK, Martin PITTERMANN, Marek CEDL [View]
[Download]

Abstract: This paper presents research motivated by industrial demand for special traction drive topology devoted to minimization of traction transformer weight against topology with classical 50Hz traction transformer. The main attention has been given to the control strategy of the special traction drive topology for AC power systems. The proposed converter control algorithm of innovative traction topology with middle-frequency transformer has been described in detail. The theoretical conclusions and simulation results are compared with experimental measurements on laboratory model with rated power of 4kVA.

   Poly-Phased Matrix Converter for large Synchronous Generators - Design of the Voltage Surge Protection
By Antoine BEGUIN, Alfred RUFER, Alain LACAZE [View]
[Download]

Abstract: This paper introduces a special mx3 matrix converter connected between the stator of a poly-phased synchronous generator and a power grid. Some commutations of the chosen switching scheme induce voltage surges due to leakage inductances of the generator. This paper then presents an analysis of a passive solution using capacitive and resistive elements to control the magnitude of this voltage overshoot. In particular, it provides a design tool based on a simplified equivalent circuit and calculates the losses through the additional resistive part. Simulation results and practical measurements confirm the theoretical predictions. From this analysis, it is then possible to assess the suggested power generation arrangement further.

   Semiconductors power losses estimation method for matrix converter applications
By Jose-Luis GALVEZ, Xavier PERPINYA, Xavier JORDA, Miquel VELLVEHI, Jose MILLAN [View]
[Download]

Abstract: This work proposes an accurate method to calculate the semiconductor power losses in a Matrix Converter (MC). It is based on the static and dynamic characterization of the power devices within a bidirectional switch (BDS). Direct applications of the proposed method are, for example, the selection of the optimum power semiconductors to implement MC and cooling systems design.

   Stability of Matrix Converter-fed Permanent Magnet Brushless Motor Drive Systems
By Jiabin WANG [View]
[Download]

Abstract: This paper analyses the stability of matrix converter-fed permanent magnet brushless AC motor drive systems. By employing state-space averaging technique, the governing equations for the dynamics of the drive system are derived. The stability of the system is analyzed by computing the eigenvalues of the Jacobian matrix of the linearized state-space equation under a given operating condition. It is shown that if the voltage transfer relation of a matrix converter is not ideal, the stability boundary of the converter-fed drive system will be influenced by its current/speed control loop bandwidth, and modulation strategies as well as the direction of the power flow (motoring or regeneration). The analytical prediction is validated by extensive time domain simulations. The findings of the paper provide an important understanding of how the drive control should be designed to maximize the stability margin for four quadrant operations.

EPE 2009 - Subtopic 05-5 - DS: 'Matrix Converters'
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2009 - Conference > EPE 2009 - Topic 05: 'Hard Switching Converters and Control' > EPE 2009 - Subtopic 05-5 - DS: 'Matrix Converters'
	[return to parent folder]

	A Modified Carrier-Based Modulation Method for Three-Phase Matrix Converters By Panagiotis POTAMIANOS, Epaminondas MITRONIKAS, Athanasios SAFACAS	[View] [Download]
Abstract: A modified carrier-based modulation method for three-phase matrix converters is proposed. This method enhances the MC performance comparing to the â€œconventionalâ€ carrier-based modulation methods in regard to the switching losses and the output voltage harmonic distortion. The output current waveform is also improved in the case of the proposed modulation method with 8 commutations per switching period (TSW), but it is deteriorated in the case of 12 commutations per TSW. Due to the fact that the proposed method is applicable when that the desired voltage transfer ratio is less than 50\%, the control algorithm also adapts a carrier-based modulation method for the cases of voltage transfer ratio larger than 50\%, which is also used for comparison and evaluation of the proposed method.

	An experimental study on induction motor drive with a single phase - three phasematrix converter By Kazuyuki IINO, Keiichiro KONDO, Yukihiko SATO	[View] [Download]
Abstract: This paper deals with a control method and a designing method of the capacitance of the compensation capacitor for a single phase to three phase matrix converters (MCs) with the variable speed drive capability of induction motors (IMs). Assuming the application of railway tractions, automobiles and elevators, motors drive inertial load. In such cases, both the load power and the load voltage increase in proportion to the rotor speed. The amplitude of the compensation capacitor voltage is controlled to absorb the single phase power fluctuation, along with the load power. We propose a method to decide the input side parameters such as the capacitance of the compensation capacitor, considering the input voltage and the power of the IM. We experimentally verify that a single phase to three phase MC can drive IMs with the proposed method.

	Comparison between back-to-back and matrix converter drives under faulty conditions By SÃ©rgio CRUZ, Marco FERREIRA	[View] [Download]
Abstract: This paper presents a comparison study between the operation of a back-to-back and a matrix converter induction motor drive under the presence of faults in the power switches of these converters. These two topologies are functionally equivalent in terms of input power quality and energy regeneration capabilities but need to be compared in terms of performance under faulty conditions as well due to the high number of switches involved in these two converters. In particular, the total waveform distortion of the input/output currents of the two converters and the motor torque oscillations were measured with the aim to determine which converter performs better under faulty conditions. Based on simulation results obtained with a detailed model of the two drive systems, it is shown that the distortions of the input/output currents caused by a single-fault in a matrix converter are approximately identical to the ones that appear in a back-to-back converter with two faults, one in the rectifier stage and the other one in the inverter stage. On the other hand, the back-to-back converter is perfectly capable of operating with an open-circuit fault provided that it is located in the rectifier stage, being the operation of the motor practically unaffected in that case. In general terms it can be said that due to the absence of an energy storage element, the matrix converter is particular sensitive to the appearance of faults. The back-to-back converter, on the other hand, is capable of maintaining a better quality of operation of the motor under faulty conditions, provided that the faults are not located in the inverter stage.

	Comparison of Three Switching Strategies for Indirect Matrix Converter By Alireza JAHANGIRI, Ahmad RADAN, Mehdi HAGHSHENAS	[View] [Download]
Abstract: The Indirect Matrix Converter (IMC) concept has been gaining recognition as a promising circuit alternative in recent years. An IMC has separate line and load side converters. Each switching period of line side converter is split into two portions. In each portion, the IMC is equivalent to a conventional inverter. Thus, output voltage can be obtained through applying a kind of space vector PWM to the load side converter. Conventional space vector pulsewidth modulation (CSVPWM) employs conventional switching sequence, which divides the zero vector time equally between two zero states in each modulation cycle. If a double edge CSVPWM used in each portion, each switch of the load side converter would have a switching frequency twice the sampling frequency. Therefore, bus-clamping PWM (BCPWM) techniques which use only one zero state in each modulation cycle can be used to reduce the switching frequency. This paper comprises two types of BCPWM techniques and a new special type of switching sequences, termed here as â€œsawthooth sequencesâ€. The proposed technique: 1) reduces the load side converter switching frequency and losses; 2) has good performance in viewpoint of input/output waveform quality 3) has switching losses independent of output power factor. Simulation results are presented to demonstrate the validity of the proposed space vector modulation technique.

	Control Strategy of an Indirect Matrix Converter with Modifying DC voltage By ruben PENA, roberto CARDENAS, eduardo REYES, pat WHEELER, jon CLARE	[View] [Download]
Abstract: The Indirect Matrix Converter (IMC) consists of an input matrix converter stage and an output voltage source inverter (VSI) stage. The input matrix converter provides the DC voltage needed for the output stage. Usually, the switching sequences of the input and output stages are arranged to have soft switching commutation at the input stage. The capability of the input matrix converter to generate produce different DC voltages is exploited in this paper. If the converter can operate at a reduced DC voltage then commutation of the VSI can take place at lower voltages. Depending on the required output voltage, the modulation of the input matrix converter is changed in order to obtain a lower/higher DC voltage without causing over modulation The strategy could be applied to a cage induction machine drive, operating at low speed and therefore requiring low voltage, or a doubly-fed induction machine drive operating near synchronous speed where the required rotor voltage is smaller. The strategy is experimentally validated controlling the output current of the IMC feeding a resistive-inductive load. Experimental results are shown for step changes in demanded reference currents and current regulation at different modulation strategies of the input converter.

	Diagnosis of open-circuit faults in matrix converters By SÃ©rgio CRUZ, Marco FERREIRA, AntÃ³nio CARDOSO	[View] [Download]
Abstract: This paper presents a new diagnostic technique, known as the Modulated Error Voltages (MEV), for the diagnosis of open-circuits faults in the power switches of matrix converters. The proposed technique is based on the monitoring of nine modulated output error voltages, each one associated to a bidirectional switch of the converter. For each output phase, an error voltage is calculated and subsequently modulated by the gate signals of each one of the three bidirectional switches connected to that specific phase. Each modulated signal is subsequently averaged over a certain period of time. If at the end of this averaging period the obtained value is higher than a threshold limit, it will trigger the indication of an open-circuit fault in the power switch associated to the monitored signal. By using the MEV it is possible to concurrently detect and locate open-circuit faults, independently of the type of load of the matrix converter or its operating conditions, namely amplitude and frequency of the output voltages, both in steady-state and transient regimes. Moreover, the MEV allows to speed up the diagnostic process when compared to other diagnostic techniques, and can easily deal with the presence of multiple faults occurring simultaneously.

	Improvement of Output Voltage Waveform for ARCP Matrix Converter By Takanori HATASE, Takashi ABE, Tsuyoshi HIGUCHI, Hidenori HARA	[View] [Download]
Abstract: A Matrix Converter (MC) is an AC-to-AC conversion device that can generate variable magnitude and frequency output voltage. The higher carrier frequency is selected for more accurate and low acoustic noise. However, using a high carrier frequency causes new problems, such as the increase of switching loss and premature breakdown of power device. Therefore, the auxiliary resonant commutated pole (ARCP) is applied to a MC and ARCPMC has been proposed. This paper shows how the method intended for improvement of the output voltage waveform for ARCPMC was verified using the system simulation and confirmed through experimental results.

	NEW CONTROL ALGORITHM FOR TRACTION DRIVE WITH SINGLE PHASE MATRIX CONVERTER By Pavel DRABEK, Martin PITTERMANN, Marek CEDL	[View] [Download]
Abstract: This paper presents research motivated by industrial demand for special traction drive topology devoted to minimization of traction transformer weight against topology with classical 50Hz traction transformer. The main attention has been given to the control strategy of the special traction drive topology for AC power systems. The proposed converter control algorithm of innovative traction topology with middle-frequency transformer has been described in detail. The theoretical conclusions and simulation results are compared with experimental measurements on laboratory model with rated power of 4kVA.

	Poly-Phased Matrix Converter for large Synchronous Generators - Design of the Voltage Surge Protection By Antoine BEGUIN, Alfred RUFER, Alain LACAZE	[View] [Download]
Abstract: This paper introduces a special mx3 matrix converter connected between the stator of a poly-phased synchronous generator and a power grid. Some commutations of the chosen switching scheme induce voltage surges due to leakage inductances of the generator. This paper then presents an analysis of a passive solution using capacitive and resistive elements to control the magnitude of this voltage overshoot. In particular, it provides a design tool based on a simplified equivalent circuit and calculates the losses through the additional resistive part. Simulation results and practical measurements confirm the theoretical predictions. From this analysis, it is then possible to assess the suggested power generation arrangement further.

	Semiconductors power losses estimation method for matrix converter applications By Jose-Luis GALVEZ, Xavier PERPINYA, Xavier JORDA, Miquel VELLVEHI, Jose MILLAN	[View] [Download]
Abstract: This work proposes an accurate method to calculate the semiconductor power losses in a Matrix Converter (MC). It is based on the static and dynamic characterization of the power devices within a bidirectional switch (BDS). Direct applications of the proposed method are, for example, the selection of the optimum power semiconductors to implement MC and cooling systems design.

	Stability of Matrix Converter-fed Permanent Magnet Brushless Motor Drive Systems By Jiabin WANG	[View] [Download]
Abstract: This paper analyses the stability of matrix converter-fed permanent magnet brushless AC motor drive systems. By employing state-space averaging technique, the governing equations for the dynamics of the drive system are derived. The stability of the system is analyzed by computing the eigenvalues of the Jacobian matrix of the linearized state-space equation under a given operating condition. It is shown that if the voltage transfer relation of a matrix converter is not ideal, the stability boundary of the converter-fed drive system will be influenced by its current/speed control loop bandwidth, and modulation strategies as well as the direction of the power flow (motoring or regeneration). The analytical prediction is validated by extensive time domain simulations. The findings of the paper provide an important understanding of how the drive control should be designed to maximize the stability margin for four quadrant operations.