EPE Association: NORpie 2006 - Topic 05: Control of Power Electronics and Electrical Machines

NORpie 2006 - Topic 05: Control of Power Electronics and Electrical Machines
You are here: EPE Documents > 05 - EPE Supported Conference Proceedings > NORpie - Proceedings > NORpie 2006 > NORpie 2006 - Topic 05: Control of Power Electronics and Electrical Machines

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   On Robust Control of Fixed Pattern Power Rectifiers
By H. Bevrani; T. Hiyama [View]
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Abstract: This paper addresses a new systematic method to design a robust proportional-integral (PI) controller for a three-phase sinusoidal active power rectifier based on H‡ control technique. The control design problem is reduced to solve an H‡ based static output feedback control problem. To determine the optimal gains, an iterative linear matrix inequalities algorithm is used. A classical power active rectifier example is given to demonstrate the efficiency of developed approach. The proposed robust technique is shown to maintain the robust performance and minimize the effects of disturbances, properly.

   Control Design Issues in Constant-Current Controlled Buck Converter
By M. Hankaniemi; T. Suntio; M. Karppanen [View]
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Abstract: This paper studies the issues in the control design in a buck converter under constant-current control. The transfer functions that characterize the dynamical performance of constant-current-controlled converters are derived from the corresponding two-port model of a constant-voltage buck converter by applying duality. The paper presents the controlloop design procedure for both Type-2 and Type-3 controllers by means of the control-to-output transfer function. The conventional control design is usually based on resistive loads, which actually might exclude the use of Type-2 controllers. The nominal model, however, reveals that both Type-2 and Type-3 can be used. The constant-current control has, however, tendency to increase the crossover frequency of the nominal control-to-output transfer function even a decade compared to the corresponding transfer function with resistive load. The high crossover frequency makes the control-loop design challenging and appropriate zero-pole placements for Type-3 and Type-2 controllers are proposed to tackle the design well.

   Investigation of Load Sensitivity of a PCMC Buck Converter with Output-Current-Feedforward
By M. Karppanen; M. Hankaniemi; T. Suntio [View]
[Download]

Abstract: This paper provides theoretical formulations to achieve load invariance of a switched-mode converter and investigates the load sensitivity of a peak-current-mode controlled (PCMC) buck converter with output current feedforward (OCF). Theoretically, a converter having zero output impedance would provide full load invariance. In practice, a converter can be made highly insensitive to load interactions, if unity-gain feedforward of output current is used together with peak-current-mode control. However, non-idealities of the practical implementation can deteriorate the obtainable level of insensitivity. Experimental frequency-domain measurements are used to prove the theoretical predictions.

   High Performance Mixed Signal Controllers for DC/DC Converters
By L.T. Jakobsen; M.A.E. Andersen [View]
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Abstract: This paper describes how mixed signal controllers combining a cheap microcontroller with a simple analogue circuit can offer high performance digital control for DC/DC converters. Mixed signal controllers have the same versatility and performance as DSP controllers if the microcontroller software is optimized. Two mixed signal controller designs based on the same 8-bit microcontroller are compared both theoretically and experimentally on a typical Point of Load converter. A 16-bit digital PID controller using lookup tables with a sampling frequency as high as 200 kHz implemented on the 16 MIPS, 8-bit ATTiny26 microcontroller is demonstrated.

   Delayed Signal Cancellation Method for Sequence Detection – Effect of Sampling Frequency and Harmonics
By J. Svensson; A. Sannino; M. Bongiorno [View]
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Abstract: This paper investigates issues related to practical implementation of the Delayed Signal Cancellation (DSC) method for on-line detection of positive and negative sequence components of three-phase quantities. The detection error due to non-ideal sampling frequency is calculated. Furthermore, the effect of the DSC method on estimation when harmonic components are present in the input signal is analyzed. It is shown how harmonics transfer through the DSC and how a nonideal sampling frequency affects the estimation of the harmonics. Experimental verification of the analytical results is presented.

NORpie 2006 - Topic 05: Control of Power Electronics and Electrical Machines
You are here: EPE Documents > 05 - EPE Supported Conference Proceedings > NORpie - Proceedings > NORpie 2006 > NORpie 2006 - Topic 05: Control of Power Electronics and Electrical Machines
	[return to parent folder]

	On Robust Control of Fixed Pattern Power Rectifiers By H. Bevrani; T. Hiyama	[View] [Download]
Abstract: This paper addresses a new systematic method to design a robust proportional-integral (PI) controller for a three-phase sinusoidal active power rectifier based on H‡ control technique. The control design problem is reduced to solve an H‡ based static output feedback control problem. To determine the optimal gains, an iterative linear matrix inequalities algorithm is used. A classical power active rectifier example is given to demonstrate the efficiency of developed approach. The proposed robust technique is shown to maintain the robust performance and minimize the effects of disturbances, properly.

	Control Design Issues in Constant-Current Controlled Buck Converter By M. Hankaniemi; T. Suntio; M. Karppanen	[View] [Download]
Abstract: This paper studies the issues in the control design in a buck converter under constant-current control. The transfer functions that characterize the dynamical performance of constant-current-controlled converters are derived from the corresponding two-port model of a constant-voltage buck converter by applying duality. The paper presents the controlloop design procedure for both Type-2 and Type-3 controllers by means of the control-to-output transfer function. The conventional control design is usually based on resistive loads, which actually might exclude the use of Type-2 controllers. The nominal model, however, reveals that both Type-2 and Type-3 can be used. The constant-current control has, however, tendency to increase the crossover frequency of the nominal control-to-output transfer function even a decade compared to the corresponding transfer function with resistive load. The high crossover frequency makes the control-loop design challenging and appropriate zero-pole placements for Type-3 and Type-2 controllers are proposed to tackle the design well.

	Investigation of Load Sensitivity of a PCMC Buck Converter with Output-Current-Feedforward By M. Karppanen; M. Hankaniemi; T. Suntio	[View] [Download]
Abstract: This paper provides theoretical formulations to achieve load invariance of a switched-mode converter and investigates the load sensitivity of a peak-current-mode controlled (PCMC) buck converter with output current feedforward (OCF). Theoretically, a converter having zero output impedance would provide full load invariance. In practice, a converter can be made highly insensitive to load interactions, if unity-gain feedforward of output current is used together with peak-current-mode control. However, non-idealities of the practical implementation can deteriorate the obtainable level of insensitivity. Experimental frequency-domain measurements are used to prove the theoretical predictions.

	High Performance Mixed Signal Controllers for DC/DC Converters By L.T. Jakobsen; M.A.E. Andersen	[View] [Download]
Abstract: This paper describes how mixed signal controllers combining a cheap microcontroller with a simple analogue circuit can offer high performance digital control for DC/DC converters. Mixed signal controllers have the same versatility and performance as DSP controllers if the microcontroller software is optimized. Two mixed signal controller designs based on the same 8-bit microcontroller are compared both theoretically and experimentally on a typical Point of Load converter. A 16-bit digital PID controller using lookup tables with a sampling frequency as high as 200 kHz implemented on the 16 MIPS, 8-bit ATTiny26 microcontroller is demonstrated.

	Delayed Signal Cancellation Method for Sequence Detection – Effect of Sampling Frequency and Harmonics By J. Svensson; A. Sannino; M. Bongiorno	[View] [Download]
Abstract: This paper investigates issues related to practical implementation of the Delayed Signal Cancellation (DSC) method for on-line detection of positive and negative sequence components of three-phase quantities. The detection error due to non-ideal sampling frequency is calculated. Furthermore, the effect of the DSC method on estimation when harmonic components are present in the input signal is analyzed. It is shown how harmonics transfer through the DSC and how a nonideal sampling frequency affects the estimation of the harmonics. Experimental verification of the analytical results is presented.