EPE Association: EPE 1997 – 53: Dialogue Session DS4d: CONVERTER CONTROL: APPLICATIONS TO THREE PHASE SYSTEMS

EPE 1997 – 53: Dialogue Session DS4d: CONVERTER CONTROL: APPLICATIONS TO THREE PHASE SYSTEMS
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1997 - Conference > EPE 1997 – 53: Dialogue Session DS4d: CONVERTER CONTROL: APPLICATIONS TO THREE PHASE SYSTEMS

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   THREE-PHASE POWER REVERSIBLE CONVERTER WITH SIMPLE CONTROL ALGORITH
By Bor-Ren Lin; Deng-Ping Wu; Tian-Fure Shiue [View]
[Download]

Abstract: This paper presents a three-phase AC to DC converter employing a new space vector modulation strategy. The addition of hysteresis current control technique can simplify the hardware circuit and reduce the cost. Finally simulated and experimental results are presented to verify the characteristics of unity power factor, sinusoidal input current, and bidirectional power flow capability.

   ANALYSIS OF DIRECT SELF CONTROL IN VOLTAGE-TYPE PWM RECTIFIER
By V. Valouch; J. Skramlik [View]
[Download]

Abstract: The paper presents an investigation of using the principle of the Direct Self Control (DSC) in control systems of PWM rectifiers. Active and reactive line powers, and the reference value of an output de voltage are control variables. Based on the results of a computer simulation a code for the digital signal processor DSP 96002 has been written and tested by an emulation system developed.

   OPTIMIZATION OF THE AC/DC/AC CONVERTER CURRENT CONTROL LOOP
By Andrzej Sikorski [View]
[Download]

Abstract: In the paper, AC/DC/AC converter, ensuring the high quality of energy conversion is presented. The following solutions minimizing the converter power losses were applied:
-the common quasi-resonant circuit for both AC!DC and DC/AC parts of converter, what makes possible the transistor switching with zero voltage,
-the control method minimizing the number of each individual converter devices switching ,
-the analyze of the control conditions of both parts of converter for further minimization of switching number.
The proposed system scheme, a methods of its control as well results of a computer simulations and laboratory investigations are presented in the paper.

   A NEW METHOD OF CONTROLLING A Q-PULSE THYRISTOR CONVERTER USING A SINGLE SYNCHRONIZATION VOLTAGE
By Stanislaw Kapka [View]
[Download]

Abstract: The article proposes an incremental measurement loop with a phase locked loop used to generate a precise linear phase scale with an M. number of markers distributed equally in a supportive synchronization voltage period. A new incremental frequency method of CJ.angle shaping has been proposed. It uses the moment of passing through zero of a specified single synchronization voltage to synchronize the moments of q-thyristors turn-on. It has been shown that it is possible to realize the digital algorithm of individual controlling a q-pulse thyristor power module with the possibility of shaping CJ.-angle in the real time. basing on two simple statements: + 1 Increment and -1 Decrement repeated with appropriate frequencies. It has also been shown that a possible maximum negative angle increase -L'1CJ.=30°. and the maximum positive angle increase can equal CJ.max. The dCJ./dt speed of changes depends on the f_x frequency value and it can be shaped freely. depending on the previously defined target function. The proposed method uses active global limitations of the alpha-min. alpha-max type as well as current and voltage limitations. It is characterized by easy cooperation with the uP. system. the PID controller. It has the dynamic properties of an equivalent phase control method in the analog version.

   NEW CONTROL STRATEGIES FOR HIGH POWER, CURRENT-SOURCE, PWM RECTIFIERS USING INSTANTANEOUS SPATIAL VECTOR TECHNIQUE
By J. Sakly; S. Toumia; S. Hassine; N. Bouguila; C. Rombaut; J. P. Cambronne [View]
[Download]

Abstract: In PWM power electronic converters, switching times increase as the power delivered will be high. The minimum conduction time causes a limitation in the reproducibility of reference spatial vector when this technique is applied. Consequently, the power delivered will be reduced. Taking this constraint in to account, new control strategies for high power, current source PWM rectifiers using instantaneous space vector technique have been developed and will be shown in this paper. In order to select the optimum control sequence, simulation results will be also presented.

   INCLUSION OF DEAD-TIME AND PARAMETER VARIATIONS IN VSC MODELLING FOR PREDICTING RESPONSES OF GRID VOLTAGE HARMONICS
By Jan Svensson [View]
[Download]

Abstract: A discrete regulator-controlled VSC connected to the grid is analysed by discrete state equations and by the use of the average switch model method. The controller takes into account the dead-time, caused by the calculation time of the controller, as well as parameter variations. All transfer functions from one voltage component (d or q) to one current component (d or q) have the same gain characteristics. The gain of the grid voltages increases when the frequency increases. The gain has a maximum at approximately 20 % of the sample frequency and decreases rapidly at higher frequencies. The maximum gain is higher for the direct coupling of d and q-voltage to d- and q-current than for the cross coupling. The gain becomes higher when the estimated inductance is smaller than the correct inductance value. Both the d- and q-components of the voltage will fluctuate when the phase voltage harmonic components have the same amplitude in all three phases. The gain of the transfer function from the phase voltage to the grid current becomes higher than those of the d- and q- component transfer functions. The gain is still low at low frequencies resulting in a nearly sinusoidal current waveform.

   Direct Voltage Control of a PWM AC/DC Voltage Converter
By G. D. Marques; J. Fernando Silva [View]
[Download]

Abstract: This paper presents a control method for voltage type PWM AC to DC converters. This method is based on the direct control of two quantities: the DC capacitor voltage, via the direct current and the AC quadrature line current. Two hysteresis controllers in rotating frame coordinates are used. The control system is useful for inverter or rectifier operations. The method presents high performances. Detailed simulation results shows that the control system has good steady state and transient characteristics.

   IDENTIFICATION AND COMPENSATION OF THE DEAD TIME BEHAVIOUR OF AN INVERTER
By Th. Baumann [View]
[Download]

Abstract: The knowledge of the output voltage of an inverter is required to obtain a high robustness of the (encoderless) field oriented control of an induction machine. The paper presents one method of self parametrisation of an inverter-fed induction machine drive. This approach identifies the parameters for dead time compensation and the stator resistance of the induction machine at stand-still. This method is implemented in inverters for different power ranges as one part of the parameter identification at stand still.

EPE 1997 – 53: Dialogue Session DS4d: CONVERTER CONTROL: APPLICATIONS TO THREE PHASE SYSTEMS
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1997 - Conference > EPE 1997 – 53: Dialogue Session DS4d: CONVERTER CONTROL: APPLICATIONS TO THREE PHASE SYSTEMS
	[return to parent folder]

	THREE-PHASE POWER REVERSIBLE CONVERTER WITH SIMPLE CONTROL ALGORITH By Bor-Ren Lin; Deng-Ping Wu; Tian-Fure Shiue	[View] [Download]
Abstract: This paper presents a three-phase AC to DC converter employing a new space vector modulation strategy. The addition of hysteresis current control technique can simplify the hardware circuit and reduce the cost. Finally simulated and experimental results are presented to verify the characteristics of unity power factor, sinusoidal input current, and bidirectional power flow capability.

	ANALYSIS OF DIRECT SELF CONTROL IN VOLTAGE-TYPE PWM RECTIFIER By V. Valouch; J. Skramlik	[View] [Download]
Abstract: The paper presents an investigation of using the principle of the Direct Self Control (DSC) in control systems of PWM rectifiers. Active and reactive line powers, and the reference value of an output de voltage are control variables. Based on the results of a computer simulation a code for the digital signal processor DSP 96002 has been written and tested by an emulation system developed.

	OPTIMIZATION OF THE AC/DC/AC CONVERTER CURRENT CONTROL LOOP By Andrzej Sikorski	[View] [Download]
Abstract: In the paper, AC/DC/AC converter, ensuring the high quality of energy conversion is presented. The following solutions minimizing the converter power losses were applied: -the common quasi-resonant circuit for both AC!DC and DC/AC parts of converter, what makes possible the transistor switching with zero voltage, -the control method minimizing the number of each individual converter devices switching , -the analyze of the control conditions of both parts of converter for further minimization of switching number. The proposed system scheme, a methods of its control as well results of a computer simulations and laboratory investigations are presented in the paper.

	A NEW METHOD OF CONTROLLING A Q-PULSE THYRISTOR CONVERTER USING A SINGLE SYNCHRONIZATION VOLTAGE By Stanislaw Kapka	[View] [Download]
Abstract: The article proposes an incremental measurement loop with a phase locked loop used to generate a precise linear phase scale with an M. number of markers distributed equally in a supportive synchronization voltage period. A new incremental frequency method of CJ.angle shaping has been proposed. It uses the moment of passing through zero of a specified single synchronization voltage to synchronize the moments of q-thyristors turn-on. It has been shown that it is possible to realize the digital algorithm of individual controlling a q-pulse thyristor power module with the possibility of shaping CJ.-angle in the real time. basing on two simple statements: + 1 Increment and -1 Decrement repeated with appropriate frequencies. It has also been shown that a possible maximum negative angle increase -L'1CJ.=30°. and the maximum positive angle increase can equal CJ.max. The dCJ./dt speed of changes depends on the f_x frequency value and it can be shaped freely. depending on the previously defined target function. The proposed method uses active global limitations of the alpha-min. alpha-max type as well as current and voltage limitations. It is characterized by easy cooperation with the uP. system. the PID controller. It has the dynamic properties of an equivalent phase control method in the analog version.

	NEW CONTROL STRATEGIES FOR HIGH POWER, CURRENT-SOURCE, PWM RECTIFIERS USING INSTANTANEOUS SPATIAL VECTOR TECHNIQUE By J. Sakly; S. Toumia; S. Hassine; N. Bouguila; C. Rombaut; J. P. Cambronne	[View] [Download]
Abstract: In PWM power electronic converters, switching times increase as the power delivered will be high. The minimum conduction time causes a limitation in the reproducibility of reference spatial vector when this technique is applied. Consequently, the power delivered will be reduced. Taking this constraint in to account, new control strategies for high power, current source PWM rectifiers using instantaneous space vector technique have been developed and will be shown in this paper. In order to select the optimum control sequence, simulation results will be also presented.

	INCLUSION OF DEAD-TIME AND PARAMETER VARIATIONS IN VSC MODELLING FOR PREDICTING RESPONSES OF GRID VOLTAGE HARMONICS By Jan Svensson	[View] [Download]
Abstract: A discrete regulator-controlled VSC connected to the grid is analysed by discrete state equations and by the use of the average switch model method. The controller takes into account the dead-time, caused by the calculation time of the controller, as well as parameter variations. All transfer functions from one voltage component (d or q) to one current component (d or q) have the same gain characteristics. The gain of the grid voltages increases when the frequency increases. The gain has a maximum at approximately 20 % of the sample frequency and decreases rapidly at higher frequencies. The maximum gain is higher for the direct coupling of d and q-voltage to d- and q-current than for the cross coupling. The gain becomes higher when the estimated inductance is smaller than the correct inductance value. Both the d- and q-components of the voltage will fluctuate when the phase voltage harmonic components have the same amplitude in all three phases. The gain of the transfer function from the phase voltage to the grid current becomes higher than those of the d- and q- component transfer functions. The gain is still low at low frequencies resulting in a nearly sinusoidal current waveform.

	Direct Voltage Control of a PWM AC/DC Voltage Converter By G. D. Marques; J. Fernando Silva	[View] [Download]
Abstract: This paper presents a control method for voltage type PWM AC to DC converters. This method is based on the direct control of two quantities: the DC capacitor voltage, via the direct current and the AC quadrature line current. Two hysteresis controllers in rotating frame coordinates are used. The control system is useful for inverter or rectifier operations. The method presents high performances. Detailed simulation results shows that the control system has good steady state and transient characteristics.

	IDENTIFICATION AND COMPENSATION OF THE DEAD TIME BEHAVIOUR OF AN INVERTER By Th. Baumann	[View] [Download]
Abstract: The knowledge of the output voltage of an inverter is required to obtain a high robustness of the (encoderless) field oriented control of an induction machine. The paper presents one method of self parametrisation of an inverter-fed induction machine drive. This approach identifies the parameters for dead time compensation and the stator resistance of the induction machine at stand-still. This method is implemented in inverters for different power ranges as one part of the parameter identification at stand still.