EPE Association: EPE-PEMC 2004 - Topic 03-3: Optimal control, robust control, non-linear control

EPE-PEMC 2004 - Topic 03-3: Optimal control, robust control, non-linear control
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2004 - Conference > EPE-PEMC 2004 - Topic 03: CONTROL OF CONVERTERS > EPE-PEMC 2004 - Topic 03-3: Optimal control, robust control, non-linear control

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   A Three-Phase Single Stage Flyback Converter With Unity Power Factor
By A. M. Omar, N. A. Rahim, S. Mekhilef [View]
[Download]

Abstract: This paper presents a new technique of generating high dc voltage using three-phase power supply. The converter system is based on a single-stage power conversion using isolated flyback converter topology. Low harmonic current distortion in the ac side is considered in this design. Field Programmable Gate Array (FPGA) is used to generate the three-phase PWM pattern that control the switches and thus makes the overall circuit compact and less discrete components involved. The experimental and simulation results are compared and good agreement is reported. The laboratory model of the converter was developed and tested.

   Applying An Fpga-Based Sr Control Technique To Conventional Forward Converters To Upgrade Transient Response
By K. I. Hwu, Y. T. Yau, Yung-Shan Chou [View]
[Download]

Abstract: Field programmable gate arrays (FPGA) based control of synchronous rectification (SR) is addressed herein and applied to the conventional forward converter. In designing such an FPGA-based SR control algorithm, the energy fed back from the secondary side to the primary side of the main transformer and then to the DC link is considered to enhance transient load response. At the same time, the required deadtime zone between switches is properly tuned to get the maximum efficiency under the condition that this converter operates at full load. Eventually, the differences in transient load response between with and without the proposed FPGAbased SR control technique are demonstrated via some experimental results.

   Control Circuit Of Series Resonant Converter With Piezoelectric Ceramic Transducer
By Pawel Fabijanski, Ryszard Lagoda [View]
[Download]

Abstract: Sandwich type piezoelectric ceramic transducers are the most frequently applied source of ultrasounds in technical cleaning system. They have the ability to radiate in an ultrasonic medium, e.g. water, with maximum acoustic power when the vibration is activated by a current whose frequency equals the mechanical resonance frequency of the transducer. In resonant inverters the transducer units are part of the oscillating circuit, for which equivalent electrical circuit consist of connection in parallel: Co end RLC.

   Control For PWM AC Chopper Feeding Nonlinear Loads
By Fateh Krim, Lazhar Rahmani, Abdelouahab Bouafia [View]
[Download]

Abstract: This paper presents a novel robust control technique for PWM ac choppers with ability of generating high quality sinusoidal waveforms with adjustable amplitudes over a wide range control. For this purpose a deadbeat based digital controller has been developed to perform tight closed-loop control of the ac chopper. This controller is based on generalized predictive control (GPC) approach. A dedicated control algorithm has been developed and implemented. The proposed controller presents the advantages of allowing a very fast transient response and compensating effectively load disturbance and non-linear loads effects. Computer simulations are performed to investigate the proposed controller performance. The simulation results show that the designed controller has a good dynamic behaviour, a good rejection of impact load disturbance and is very robust. To evaluate the proposed approach an experimental prototype has been constructed. Experimental results under various loading conditions have demonstrated that the system performs well.

   Integral Control Method With Exponential Variable Integral Constant
By Algirdas Baskys, Vitold Gobis, Sergej Jegorov [View]
[Download]

Abstract: The integral control method with integral constant, witch is exponential function of error (eI method) has been suggested. Controller based on this method allows to decrease the settling time of unit step response transient of control system as compared with case when classical integral controller is used, keeping one’s the feature of high electric noise resistance, witch is characteristic for control systems based on integral controller. Investigation shows, that controller based on eI method guaranties more stable operating of control systems with time – delayed plants effected by electric noise as compared with situation when proportional – integral controller is used. The controller based on suggested control method is applied in frequency converter for automatic control of AC induction motor rotation speed.

   Sinusoidal Waveform Compensator For Optimal Digital Control Of PWM Inverter
By Toshiji Kato, Kaoru Inoue, Shinsaku Kuroda [View]
[Download]

Abstract: Not only steady-state but also fast transient performances are required for control of a sinusoidal PWM inverter. Its reference voltage waveform is not constant but sinusoidal. The output voltage is controlled to coincide with a reference waveform. However the reference varies to be a further value when the output reaches the value. So there is always a deviation between the reference and the output voltage. It is necessary to design a compensator by considering these sinusoidal variations of the reference waveform to get a good steady-state and fast transient response. This paper proposes a sort of digital repetitive control systems for a sinusoidal PWM inverter control. It is based on the internal model principle to realize a response with no deviation for a periodic sinusoidal reference input. It has a denominator z2 −2 cos ùT +1 of a transfer function which is equal to the z function of a sinusoidal waveform of the angular frequency ù and the sample time T . Compensator and feedback gains of the inverter are determined by the optimal control principles. The proposed method is investigated for actual performances and it is validated through theoretical experimental results for linear and nonlinear loads by using a DSP system at the switching frequency of 20kHz.

EPE-PEMC 2004 - Topic 03-3: Optimal control, robust control, non-linear control
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2004 - Conference > EPE-PEMC 2004 - Topic 03: CONTROL OF CONVERTERS > EPE-PEMC 2004 - Topic 03-3: Optimal control, robust control, non-linear control
	[return to parent folder]

	A Three-Phase Single Stage Flyback Converter With Unity Power Factor By A. M. Omar, N. A. Rahim, S. Mekhilef	[View] [Download]
Abstract: This paper presents a new technique of generating high dc voltage using three-phase power supply. The converter system is based on a single-stage power conversion using isolated flyback converter topology. Low harmonic current distortion in the ac side is considered in this design. Field Programmable Gate Array (FPGA) is used to generate the three-phase PWM pattern that control the switches and thus makes the overall circuit compact and less discrete components involved. The experimental and simulation results are compared and good agreement is reported. The laboratory model of the converter was developed and tested.

	Applying An Fpga-Based Sr Control Technique To Conventional Forward Converters To Upgrade Transient Response By K. I. Hwu, Y. T. Yau, Yung-Shan Chou	[View] [Download]
Abstract: Field programmable gate arrays (FPGA) based control of synchronous rectification (SR) is addressed herein and applied to the conventional forward converter. In designing such an FPGA-based SR control algorithm, the energy fed back from the secondary side to the primary side of the main transformer and then to the DC link is considered to enhance transient load response. At the same time, the required deadtime zone between switches is properly tuned to get the maximum efficiency under the condition that this converter operates at full load. Eventually, the differences in transient load response between with and without the proposed FPGAbased SR control technique are demonstrated via some experimental results.

	Control Circuit Of Series Resonant Converter With Piezoelectric Ceramic Transducer By Pawel Fabijanski, Ryszard Lagoda	[View] [Download]
Abstract: Sandwich type piezoelectric ceramic transducers are the most frequently applied source of ultrasounds in technical cleaning system. They have the ability to radiate in an ultrasonic medium, e.g. water, with maximum acoustic power when the vibration is activated by a current whose frequency equals the mechanical resonance frequency of the transducer. In resonant inverters the transducer units are part of the oscillating circuit, for which equivalent electrical circuit consist of connection in parallel: Co end RLC.

	Control For PWM AC Chopper Feeding Nonlinear Loads By Fateh Krim, Lazhar Rahmani, Abdelouahab Bouafia	[View] [Download]
Abstract: This paper presents a novel robust control technique for PWM ac choppers with ability of generating high quality sinusoidal waveforms with adjustable amplitudes over a wide range control. For this purpose a deadbeat based digital controller has been developed to perform tight closed-loop control of the ac chopper. This controller is based on generalized predictive control (GPC) approach. A dedicated control algorithm has been developed and implemented. The proposed controller presents the advantages of allowing a very fast transient response and compensating effectively load disturbance and non-linear loads effects. Computer simulations are performed to investigate the proposed controller performance. The simulation results show that the designed controller has a good dynamic behaviour, a good rejection of impact load disturbance and is very robust. To evaluate the proposed approach an experimental prototype has been constructed. Experimental results under various loading conditions have demonstrated that the system performs well.

	Integral Control Method With Exponential Variable Integral Constant By Algirdas Baskys, Vitold Gobis, Sergej Jegorov	[View] [Download]
Abstract: The integral control method with integral constant, witch is exponential function of error (eI method) has been suggested. Controller based on this method allows to decrease the settling time of unit step response transient of control system as compared with case when classical integral controller is used, keeping one’s the feature of high electric noise resistance, witch is characteristic for control systems based on integral controller. Investigation shows, that controller based on eI method guaranties more stable operating of control systems with time – delayed plants effected by electric noise as compared with situation when proportional – integral controller is used. The controller based on suggested control method is applied in frequency converter for automatic control of AC induction motor rotation speed.

	Sinusoidal Waveform Compensator For Optimal Digital Control Of PWM Inverter By Toshiji Kato, Kaoru Inoue, Shinsaku Kuroda	[View] [Download]
Abstract: Not only steady-state but also fast transient performances are required for control of a sinusoidal PWM inverter. Its reference voltage waveform is not constant but sinusoidal. The output voltage is controlled to coincide with a reference waveform. However the reference varies to be a further value when the output reaches the value. So there is always a deviation between the reference and the output voltage. It is necessary to design a compensator by considering these sinusoidal variations of the reference waveform to get a good steady-state and fast transient response. This paper proposes a sort of digital repetitive control systems for a sinusoidal PWM inverter control. It is based on the internal model principle to realize a response with no deviation for a periodic sinusoidal reference input. It has a denominator z2 −2 cos ùT +1 of a transfer function which is equal to the z function of a sinusoidal waveform of the angular frequency ù and the sample time T . Compensator and feedback gains of the inverter are determined by the optimal control principles. The proposed method is investigated for actual performances and it is validated through theoretical experimental results for linear and nonlinear loads by using a DSP system at the switching frequency of 20kHz.