EPE Association: EPE 2005 - Topic 15-4c - DS: Active, passive and combined filtering

EPE 2005 - Topic 15-4c - DS: Active, passive and combined filtering
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2005 - Conference > EPE 2005 - Topic 15: POWER ELECTRONICS IN TRANSMISSION AND DISTRIBUTION OF ELECTRICAL ENERGY > EPE 2005 - Topic 15-4c - DS: Active, passive and combined filtering

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   Active Power Filter for Harmonic Distortion Compensation of Induction Motors with Soft Starting
By DESPALATOVIC Marin; TERZIC Bozo; KILIC Tomislav [View]
[Download]

Abstract: A parallel active power filter for harmonic distortion compensation, its signal processing unit, control principle and power stage are described. Power stage of the proposed active filter is realised using three serial inductance, three-phase IGBT based current controlled voltage inverter with two symmetrical capacitors on dc bus. Three independent hysteresis controllers on the base of current references are used to generate switching signals for inverter transistors. The current references are obtained by taking the difference of load current and its fundamental harmonic. For fundamental harmonic determination with no time delay a combination of digital predictive filter and low pass filter is used. The experimental results illustrate the active power filter performance in system with induction motor drives with soft starting.

   Comparison of Series Hybrid Active Power Filters Based on Experimental Tests
By TURUNEN Juha; TUUSA Heikki; SALO Mika [View]
[Download]

Abstract: Current harmonics are the one of the problems associated with the power networks. They are caused by non-linear loads including e.g. saturated transformers, arc furnaces and equipment including semiconductor switches. Because of current harmonics, voltage harmonics are produced. The presence of voltage harmonics in the power network is harmful, because additional losses are caused and in the worst case malfunctioning of the network components may occur. Because of these harmful effects, national and international standards have been created to limit current harmonics. The current harmonics can be reduced by using current filters, which can be divided into passive power filters, active power filters and hybrid power filters. In this paper, a comparison of three series hybrid active power filters is presented. After a short introduction to the topic the operating principles of the main circuits and control systems of these filters are presented. The rest of the paper presents the experimental tests, where the current filtering performance of each filter is tested. Tests are performed for each filter topology in the same operation conditions using filter prototypes. The performance of the filters is tested in cases where harmonics producing loads are 5 kVA three-phase diode rectifiers with RL- and RC-loads. The current filtering performance of the series hybrid active power filters presented is compared based on the presented test results.

   Control strategy for hybrid active filters leading to reduced inverter rating
By ASIMINOAEI L.; DANIEL BENJAMIN Doniga; GEORGE DAN Stan; TEODORESCU Remus; MAGUREANU R.; BLAABJERG Frede [View]
[Download]

Abstract: In this paper a parallel hybrid filter is studied for current harmonic compensation. The hybrid filter is formed by a single tuned LC filter per phase and a small-rated power three-phase active filter, which are directly connected in series without any matching transformer. The required rating of the active filter is much smaller than a conventional standalone active filter would be. No additional switching-ripple filter is required for the hybrid filter because the LC filter functions not only as a harmonic filter but also as a switching-ripple filter around 10 kHz. Simulation results and experimental results obtained in laboratory confirmed the validity and effectiveness of the control.

   Development of Power Quality Controller in Parallel to Dispersed Power Source
By KONISHI Hiroo [View]
[Download]

Abstract: The dispersed generations (DGs) are expected to increase. The output power of DGs fluctuates, making AC system interconnection problematic. As DC-to-AC converters of DGs generate harmonics, the harmonics lead to degradation of power quality, too. In the paper, we explain the control method for smoothing power fluctuations and the principle and operation of the active filter function of PQC. We also describe the results of operational verification tests we conducted using a 7-kVA prototype in a simulated transmission. The test results show that the PQC held system voltage fluctuations to under 8\% even in large power changes and reduced 5th and 7th harmonics by less than 30\%. Finally, the power quality controller is confirmed to be useful for improving power quality of AC grid systems introduced dispersed generations.

   Flicker Mitigation with the Smarttrafo
By BAUER Pavol; ABDULRAHMAN Haitham [View]
[Download]

Abstract: In this paper a new method to mitigate a cyclic voltage flicker using electronically switched tap changed transformer is investigated. The idea of this method is based on injection of a signal, with the same frequency rate as that of the flicker, into the feedback path of the controller. This method utilizing electronically controlled tap-changed transformer provides flicker free secondary voltage. Further the cause of the internal flicker is searched. A new switching technique implemented to control a single-phase or three phase tap changed transformer in order to eliminate the internal flicker problem is proposed. The suggested method was subjected to both theoretical and experimental investigations.

   Linear closed-loop control of active power filter
By GAUBERT Jea; DEWEZ Claude; RAMBAULT Laurent [View]
[Download]

Abstract: This paper presents a parallel active power filter which is intended for eliminating the unwanted harmonics. A novel linear model of a three-phase network is proposed and allows the use of tools developed for linear control theory. Moreover, with the same tools, uncertainties of physical parameters can be taken into account. Theoretical analysis, complete simulation of the system and experimental results are presented to confirm the validity of the proposed technique.

   Novel Estimator of Distorted and Unbalanced Electromotive Force of the Grid for Control System of PWM Rectifier with Active Filtering
By WOJCIECHOWSKI Daniel [View]
[Download]

Abstract: Control of PWM rectifier with active filtering is realized by fast and precise shaping of its AC currents. In the paper the control system with predictive algorithms of both set currents calculation and currents control is proposed. These algorithms provide very high accuracy and dynamics of AC currents shaping which is limited only by parameters of the power circuits. In both algorithms calculations are based on precise information about present and future samples of in general distorted and unbalanced equivalent electromotive force (emf) of the grid. For this purpose the novel, grid voltages sensorless, precise estimator and predictor of grid emf is proposed. This robust algorithm is based on digital signal processing techniques and requires relatively low computational effort. In this paper the simulations and experimental results are presented which show the performance of proposed estimator and predictor of grid emf and its influence on operation of the control system of PWM rectifier with active filtering.

   Properties, Simulations and Experimental Investigation of the Series-Parallel Active Power Filters
By RUSINSKI Jacek; JARNUT Marcin; STRZELECKI Ryszard [View]
[Download]

Abstract: In this paper introduced calculate method of active power filters passive components, simulation and experimental researches results of the series-parallel active power filter. Authors especially occupy oneself with analysis power flow between both active filters in UPQC system and nonlinear load. This problem is according to authors very important, because it makes possible to find optimum configuration of the hybrid UPFC and power of the additional sources elements.

   Sliding mode control of DVR with minimized energy injection
By PIATEK Krzysztof [View]
[Download]

Abstract: DVR is a power electronic device designed to maintain constant voltage amplitude, thus protect sensitive loads against voltage dips. This paper presents a new concept of DVR control. The DVR injects the missing voltage, so the load voltage follows the reference voltage. The DVR unit is controlled by a sliding mode controller, and shows very good performance. The DVR maintains a small angle between the load voltage phasor and supply voltage phasor, so the injected active power can be minimized.

   Stable Control Method of Source Current Detection Type Active Filter by Voltage Harmonics Feedback
By HOJO Masahide; UEKI Kenichiro; OHNISHI Tokuo [View]
[Download]

Abstract: In recent years, voltage distortion on a power distribution line becomes a serious problem. Active filters are known as useful methods for harmonic mitigation methods. A source current detection type current active filter features a simple control system and robustness of its detector gain variation. However, it may cause serious oscillation problems depending on system parameters. This paper proposes a new control method for the active filter to suppress a terminal voltage distortion as well as to prevent the oscillations. The proposed active filter equips a feedback loop of terminal voltage harmonics in addition to the source current detection. When the feedback gain of terminal voltage harmonics is relatively small, the feedback loop works well for preventing the system oscillation problem. As the feedback gain increases, the feedback loop shows effectiveness on suppressing a terminal voltage distortion as well as preventing the oscillation. This paper confirms the operating characteristics of the active filter by some simulation and experimental studies.

   The Active Power Filter Operation Under The Distorted Supply Voltage
By FIRLIT Andrzej Krzysztof [View]
[Download]

Abstract: The aim of this paper is comparing the control algorithms based on the p-q power theory with those employing the power theory based on the current’s physical components theory, for the three-phase shunt active power filters. The comparison concerns the aspects of: filtering current harmonics, reactive power compensation and load balancing. The active power filter operation under the distorted voltage supply at the point of common coupling and the source non-zero internal impedance conditions is considered. The results of both: the simulation in the Matlab/Simulink environment and the laboratory investigation, using the fast prototyping system dSPACE, are given in the paper.

   Three-phase Active Power Filter Using the Sliding DFT Control Algorithm
By JARNUT Marcin; SOZANSKI Krzysztof [View]
[Download]

Abstract: This paper describes the sliding discrete Fourier transform (DFT) algorithm as an alternative for typical DFT used for spectrum analysis and synthesis. As an example a control circuit for a three-phase 75 kVA parallel active power filter (APF) is used. Such filters have been built and tested. Some illustrative, experimental results are also presented in the paper. The control algorithms of the proposed APF are implemented in the fixed-point digital signal processor TMS320C50. The presented control APF algorithm is a good alternative to classical APF control algorithms, because it allows easy selection of control parameters in mains currents: imbalance, reactive power or harmonics contents. In the proposed circuit transient performance of APF is improved using non-causal predictive current compensation.

   Voltage Power Line Conditioner - Voltage Restoring Mode
By STRZELECKI Ryszard; RUSINSKI Jacek; BENYSEK Grzegorz; SOZANSKI Krzysztof; JARNUT Marcin [View]
[Download]

Abstract: Paper describes modified structure of voltage source power line conditioner. The principals ofoperation and basic properties in voltage restoring mode have been introduced. Some simulationresults in typical disturbance of distribution network voltage cases have been obtained and discussed.Especially the effectiveness of load voltage conditioning in connection with input power factorcompensation are the thesis of this work. The comparative consideration of symmetrical power lineconditioner SPLC with modern on-line UPS systems can be found also inside.

EPE 2005 - Topic 15-4c - DS: Active, passive and combined filtering
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2005 - Conference > EPE 2005 - Topic 15: POWER ELECTRONICS IN TRANSMISSION AND DISTRIBUTION OF ELECTRICAL ENERGY > EPE 2005 - Topic 15-4c - DS: Active, passive and combined filtering
	[return to parent folder]

	Active Power Filter for Harmonic Distortion Compensation of Induction Motors with Soft Starting By DESPALATOVIC Marin; TERZIC Bozo; KILIC Tomislav	[View] [Download]
Abstract: A parallel active power filter for harmonic distortion compensation, its signal processing unit, control principle and power stage are described. Power stage of the proposed active filter is realised using three serial inductance, three-phase IGBT based current controlled voltage inverter with two symmetrical capacitors on dc bus. Three independent hysteresis controllers on the base of current references are used to generate switching signals for inverter transistors. The current references are obtained by taking the difference of load current and its fundamental harmonic. For fundamental harmonic determination with no time delay a combination of digital predictive filter and low pass filter is used. The experimental results illustrate the active power filter performance in system with induction motor drives with soft starting.

	Comparison of Series Hybrid Active Power Filters Based on Experimental Tests By TURUNEN Juha; TUUSA Heikki; SALO Mika	[View] [Download]
Abstract: Current harmonics are the one of the problems associated with the power networks. They are caused by non-linear loads including e.g. saturated transformers, arc furnaces and equipment including semiconductor switches. Because of current harmonics, voltage harmonics are produced. The presence of voltage harmonics in the power network is harmful, because additional losses are caused and in the worst case malfunctioning of the network components may occur. Because of these harmful effects, national and international standards have been created to limit current harmonics. The current harmonics can be reduced by using current filters, which can be divided into passive power filters, active power filters and hybrid power filters. In this paper, a comparison of three series hybrid active power filters is presented. After a short introduction to the topic the operating principles of the main circuits and control systems of these filters are presented. The rest of the paper presents the experimental tests, where the current filtering performance of each filter is tested. Tests are performed for each filter topology in the same operation conditions using filter prototypes. The performance of the filters is tested in cases where harmonics producing loads are 5 kVA three-phase diode rectifiers with RL- and RC-loads. The current filtering performance of the series hybrid active power filters presented is compared based on the presented test results.

	Control strategy for hybrid active filters leading to reduced inverter rating By ASIMINOAEI L.; DANIEL BENJAMIN Doniga; GEORGE DAN Stan; TEODORESCU Remus; MAGUREANU R.; BLAABJERG Frede	[View] [Download]
Abstract: In this paper a parallel hybrid filter is studied for current harmonic compensation. The hybrid filter is formed by a single tuned LC filter per phase and a small-rated power three-phase active filter, which are directly connected in series without any matching transformer. The required rating of the active filter is much smaller than a conventional standalone active filter would be. No additional switching-ripple filter is required for the hybrid filter because the LC filter functions not only as a harmonic filter but also as a switching-ripple filter around 10 kHz. Simulation results and experimental results obtained in laboratory confirmed the validity and effectiveness of the control.

	Development of Power Quality Controller in Parallel to Dispersed Power Source By KONISHI Hiroo	[View] [Download]
Abstract: The dispersed generations (DGs) are expected to increase. The output power of DGs fluctuates, making AC system interconnection problematic. As DC-to-AC converters of DGs generate harmonics, the harmonics lead to degradation of power quality, too. In the paper, we explain the control method for smoothing power fluctuations and the principle and operation of the active filter function of PQC. We also describe the results of operational verification tests we conducted using a 7-kVA prototype in a simulated transmission. The test results show that the PQC held system voltage fluctuations to under 8\% even in large power changes and reduced 5th and 7th harmonics by less than 30\%. Finally, the power quality controller is confirmed to be useful for improving power quality of AC grid systems introduced dispersed generations.

	Flicker Mitigation with the Smarttrafo By BAUER Pavol; ABDULRAHMAN Haitham	[View] [Download]
Abstract: In this paper a new method to mitigate a cyclic voltage flicker using electronically switched tap changed transformer is investigated. The idea of this method is based on injection of a signal, with the same frequency rate as that of the flicker, into the feedback path of the controller. This method utilizing electronically controlled tap-changed transformer provides flicker free secondary voltage. Further the cause of the internal flicker is searched. A new switching technique implemented to control a single-phase or three phase tap changed transformer in order to eliminate the internal flicker problem is proposed. The suggested method was subjected to both theoretical and experimental investigations.

	Linear closed-loop control of active power filter By GAUBERT Jea; DEWEZ Claude; RAMBAULT Laurent	[View] [Download]
Abstract: This paper presents a parallel active power filter which is intended for eliminating the unwanted harmonics. A novel linear model of a three-phase network is proposed and allows the use of tools developed for linear control theory. Moreover, with the same tools, uncertainties of physical parameters can be taken into account. Theoretical analysis, complete simulation of the system and experimental results are presented to confirm the validity of the proposed technique.

	Novel Estimator of Distorted and Unbalanced Electromotive Force of the Grid for Control System of PWM Rectifier with Active Filtering By WOJCIECHOWSKI Daniel	[View] [Download]
Abstract: Control of PWM rectifier with active filtering is realized by fast and precise shaping of its AC currents. In the paper the control system with predictive algorithms of both set currents calculation and currents control is proposed. These algorithms provide very high accuracy and dynamics of AC currents shaping which is limited only by parameters of the power circuits. In both algorithms calculations are based on precise information about present and future samples of in general distorted and unbalanced equivalent electromotive force (emf) of the grid. For this purpose the novel, grid voltages sensorless, precise estimator and predictor of grid emf is proposed. This robust algorithm is based on digital signal processing techniques and requires relatively low computational effort. In this paper the simulations and experimental results are presented which show the performance of proposed estimator and predictor of grid emf and its influence on operation of the control system of PWM rectifier with active filtering.

	Properties, Simulations and Experimental Investigation of the Series-Parallel Active Power Filters By RUSINSKI Jacek; JARNUT Marcin; STRZELECKI Ryszard	[View] [Download]
Abstract: In this paper introduced calculate method of active power filters passive components, simulation and experimental researches results of the series-parallel active power filter. Authors especially occupy oneself with analysis power flow between both active filters in UPQC system and nonlinear load. This problem is according to authors very important, because it makes possible to find optimum configuration of the hybrid UPFC and power of the additional sources elements.

	Sliding mode control of DVR with minimized energy injection By PIATEK Krzysztof	[View] [Download]
Abstract: DVR is a power electronic device designed to maintain constant voltage amplitude, thus protect sensitive loads against voltage dips. This paper presents a new concept of DVR control. The DVR injects the missing voltage, so the load voltage follows the reference voltage. The DVR unit is controlled by a sliding mode controller, and shows very good performance. The DVR maintains a small angle between the load voltage phasor and supply voltage phasor, so the injected active power can be minimized.

	Stable Control Method of Source Current Detection Type Active Filter by Voltage Harmonics Feedback By HOJO Masahide; UEKI Kenichiro; OHNISHI Tokuo	[View] [Download]
Abstract: In recent years, voltage distortion on a power distribution line becomes a serious problem. Active filters are known as useful methods for harmonic mitigation methods. A source current detection type current active filter features a simple control system and robustness of its detector gain variation. However, it may cause serious oscillation problems depending on system parameters. This paper proposes a new control method for the active filter to suppress a terminal voltage distortion as well as to prevent the oscillations. The proposed active filter equips a feedback loop of terminal voltage harmonics in addition to the source current detection. When the feedback gain of terminal voltage harmonics is relatively small, the feedback loop works well for preventing the system oscillation problem. As the feedback gain increases, the feedback loop shows effectiveness on suppressing a terminal voltage distortion as well as preventing the oscillation. This paper confirms the operating characteristics of the active filter by some simulation and experimental studies.

	The Active Power Filter Operation Under The Distorted Supply Voltage By FIRLIT Andrzej Krzysztof	[View] [Download]
Abstract: The aim of this paper is comparing the control algorithms based on the p-q power theory with those employing the power theory based on the current’s physical components theory, for the three-phase shunt active power filters. The comparison concerns the aspects of: filtering current harmonics, reactive power compensation and load balancing. The active power filter operation under the distorted voltage supply at the point of common coupling and the source non-zero internal impedance conditions is considered. The results of both: the simulation in the Matlab/Simulink environment and the laboratory investigation, using the fast prototyping system dSPACE, are given in the paper.

	Three-phase Active Power Filter Using the Sliding DFT Control Algorithm By JARNUT Marcin; SOZANSKI Krzysztof	[View] [Download]
Abstract: This paper describes the sliding discrete Fourier transform (DFT) algorithm as an alternative for typical DFT used for spectrum analysis and synthesis. As an example a control circuit for a three-phase 75 kVA parallel active power filter (APF) is used. Such filters have been built and tested. Some illustrative, experimental results are also presented in the paper. The control algorithms of the proposed APF are implemented in the fixed-point digital signal processor TMS320C50. The presented control APF algorithm is a good alternative to classical APF control algorithms, because it allows easy selection of control parameters in mains currents: imbalance, reactive power or harmonics contents. In the proposed circuit transient performance of APF is improved using non-causal predictive current compensation.

	Voltage Power Line Conditioner - Voltage Restoring Mode By STRZELECKI Ryszard; RUSINSKI Jacek; BENYSEK Grzegorz; SOZANSKI Krzysztof; JARNUT Marcin	[View] [Download]
Abstract: Paper describes modified structure of voltage source power line conditioner. The principals ofoperation and basic properties in voltage restoring mode have been introduced. Some simulationresults in typical disturbance of distribution network voltage cases have been obtained and discussed.Especially the effectiveness of load voltage conditioning in connection with input power factorcompensation are the thesis of this work. The comparative consideration of symmetrical power lineconditioner SPLC with modern on-line UPS systems can be found also inside.