Multiple-Period Repetitive Controller for Selective Harmonic Compensation with Three-Phase Shunt Active Power Filter

Chao Zhang,Maofa Gong,Yijun Zhang,Yuxia Li 전력전자학회 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.3

This paper presents a shunt active power filter (SAPF) for compensating inter-harmonics and harmonics when inter-harmonics content is evident in the grid. The principle of inter-harmonics generation in the grid was analyzed, and the inter-harmonics effect on repetitive controllers was discussed in terms of control performance. Traditional repetitive controllers are not applicable in inter-harmonic compensation. Moreover, the effect of an ideal controller on harmonics signals was analyzed on the basis of the internal model principle. The repetitive controller was improved in the form of a basis function according to theoretical analysis. The finite-dimensional repetitive controller, which is also called the multiple-period repetitive controller, was designed for the control of multiple periodic signals. A selective harmonic compensation system was developed with SAPF. This system can be used to compensate harmonics and inter-harmonics in the grid. Finally, system control performance was verified by simulation and experimental results.

Impedance-based harmonics compensation with accurate harmonic power sharing in distorted microgrids

Pham, Minh-Duc,Lee, Hong-Hee The Korean Institute of Power Electronics 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.2

This paper presents an enhanced compensation strategy for distributed generation (DG) systems to simultaneously achieve accurate power sharing and harmonics compensation at the point of common coupling (PCC). In the proposed control strategy, the output impedance is modified at the fundamental and harmonic frequencies to compensate for the line impedance mismatches among DG units, which results in accurate power sharing. In addition, load harmonic currents are effectively adjusted by the DG units to effectively compensate the PCC voltage harmonics. Additionally, the DG equivalent impedance is regulated adaptively to ensure accurate harmonic power sharing even in the presence of sudden load changes. Furthermore, a distributed communication network is adopted instead of a central controller to increase the reliability and stability of the microgrid system. The proposed control strategy is applied to a prototype microgrid system, and its effectiveness and reliability are experimentally validated.

Multiple-Period Repetitive Controller for Selective Harmonic Compensation with Three-Phase Shunt Active Power Filter

Zhang, Chao,Gong, Maofa,Zhang, Yijun,Li, Yuxia The Korean Institute of Power Electronics 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.3

This paper presents a shunt active power filter (SAPF) for compensating inter-harmonics and harmonics when inter-harmonics content is evident in the grid. The principle of inter-harmonics generation in the grid was analyzed, and the inter-harmonics effect on repetitive controllers was discussed in terms of control performance. Traditional repetitive controllers are not applicable in inter-harmonic compensation. Moreover, the effect of an ideal controller on harmonics signals was analyzed on the basis of the internal model principle. The repetitive controller was improved in the form of a basis function according to theoretical analysis. The finite-dimensional repetitive controller, which is also called the multiple-period repetitive controller, was designed for the control of multiple periodic signals. A selective harmonic compensation system was developed with SAPF. This system can be used to compensate harmonics and inter-harmonics in the grid. Finally, system control performance was verified by simulation and experimental results.

A Hybrid Static Compensator for Dynamic Reactive Power Compensation and Harmonic Suppression

Jia-Qiang Yang,Lei Yang,Zi-peng Su 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.3

This paper presents a combined system of a small-capacity inverter and multigroup delta-connected thyristor switched capacitors (TSCs). The system is referred to as a hybrid static compensator (HSC) and has the functions of dynamic reactive power compensation and harmonic suppression. In the proposed topology, the load reactive power is mainly compensated by the TSCs. Meanwhile the inverter is meant to cooperate with TSCs to achieve continuous reactive power compensation, and to filter the harmonics generated by nonlinear loads and the TSCs. First, the structure and mathematical model of the HSC are discussed Then the control method of the HSC is presented. An improved reduced order generalized integrator (ROGI)-based selective current control method is adopted in the inverter to achieve high-performance reactive and harmonic current compensation. Meanwhile, a switch control strategy is proposed to implement precise and fast switching of the TSCs and to avoid changing the time delay needed by the conventional switch strategy. Experiments are implemented on a 20 KVA HSC prototype and the obtained results verify the validity of the proposed HSC system.

A Shunt Active Filter for Reactive Power Compensation and Harmonic Mitigation

Narayan G. Apte,Vishram N. Bapat,Amruta N. Jog 전력전자학회 2007 ICPE(ISPE)논문집 Vol.- No.-

This paper presents a digital simulation of a 3Φ Shunt Active Filter (SAF) for harmonic and reactive power compensation. The instantaneous harmonic and reactive compensating currents is desegregated in it’s three components viz., (a) fundamental reactive current (b) oscillating harmonic reactive current (c) oscillating harmonic active current. The resultant compensating current is injected to the point of common coupling (PCC) of the ac mains by a six pulse, hysteresis current controlled, Voltage Source Inverter (VSI). A high performance hysteresis band modulation technique is proposed to maintain nearly constant device switching frequency. The hysteresis bandwidth is modulated as a function of the desired switching frequency , supply voltage, DC bus voltage and slope of the reference current. Responses of simulated model clearly reveal the desired performance of SAF.

A Hybrid Static Compensator for Dynamic Reactive Power Compensation and Harmonic Suppression

Yang, Jia-qiang,Yang, Lei,Su, Zi-peng The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.3

This paper presents a combined system of a small-capacity inverter and multigroup delta-connected thyristor switched capacitors (TSCs). The system is referred to as a hybrid static compensator (HSC) and has the functions of dynamic reactive power compensation and harmonic suppression. In the proposed topology, the load reactive power is mainly compensated by the TSCs. Meanwhile the inverter is meant to cooperate with TSCs to achieve continuous reactive power compensation, and to filter the harmonics generated by nonlinear loads and the TSCs. First, the structure and mathematical model of the HSC are discussed Then the control method of the HSC is presented. An improved reduced order generalized integrator (ROGI)-based selective current control method is adopted in the inverter to achieve high-performance reactive and harmonic current compensation. Meanwhile, a switch control strategy is proposed to implement precise and fast switching of the TSCs and to avoid changing the time delay needed by the conventional switch strategy. Experiments are implemented on a 20 KVA HSC prototype and the obtained results verify the validity of the proposed HSC system.

Direct Harmonic Voltage Control Strategy of Shunt Active Power Filters Suitable for Microgrid Applications

Munir, Hafiz Mudassir,Zou, Jianxiao,Xie, Chuan,Li, Kay,Younas, Talha,Guerrero, Josep M. The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.1

The application of shunt active power filters (S-APFs) is considered to be the most popular approach for harmonic compensation due to its high simplicity, ease of installation and efficient control. Its functionality mainly depends upon the rapidness and precision of its internally built control algorithms. A S-APF is generally operated in the current controlled mode (CCM) with the detection of harmonic load current. Its operation may not be appropriate for the distributed power generation system (DPGS) due to the wide dispersion of nonlinear loads. Despite the fact that the voltage detection based resistive-APF (R-APF) appears to be more appropriate for use in the DPGS, the R-APF experiences poor performance in terms of mitigating harmonics and parameter tuning. Therefore, this paper introduces a direct harmonic voltage detection based control approach for the S-APF that does not need a remote harmonic load current since it only requires a local point of common coupling (PCC) voltage for the detection of harmonics. The complete design procedure of the proposed control approach is presented. In addition, experimental results are given in detail to validate the performance and superiority of the proposed method over the conventional R-APF control. Thus, the outcomes of this study approve the predominance of the discussed strategy.

PI and Fuzzy Logic Controller Based 3-Phase 4-Wire Shunt Active Filters for the Mitigation of Current Harmonics with the I_d-I_q Control Strategy

Mikkili, Suresh,Panda, Anup Kumar The Korean Institute of Power Electronics 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.6

Commencing with incandescent light bulbs, every load today creates harmonics. Unfortunately, these loads vary with respect to their amount of harmonic content and their response to problems caused by harmonics. The prevalent difficulties with harmonics are voltage and current waveform distortions. In addition, Electronic equipment like computers, battery chargers, electronic ballasts, variable frequency drives, and switching mode power supplies generate perilous amounts of harmonics. Issues related to harmonics are of a greater concern to engineers and building designers because they do more than just distort voltage waveforms, they can overheat the building wiring, cause nuisance tripping, overheat transformer units, and cause random end-user equipment failures. Thus power quality is becoming more and more serious with each passing day. As a result, active power filters (APFs) have gained a lot of attention due to their excellent harmonic compensation. However, the performance of the active filters seems to have contradictions with different control techniques. The main objective of this paper is to analyze shunt active filters with fuzzy and pi controllers. To carry out this analysis, active and reactive current methods ($i_d-i_q$) are considered. Extensive simulations were carried out. The simulations were performed under balance, unbalanced and non sinusoidal conditions. The results validate the dynamic behavior of fuzzy logic controllers over PI controllers.

PI and Fuzzy Logic Controller Based 3-Phase 4-Wire Shunt Active Filters for the Mitigation of Current Harmonics with the I_d-I_q Control Strategy

Suresh Mikkili,Anup Kumar Panda 전력전자학회 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.6

Commencing with incandescent light bulbs, every load today creates harmonics. Unfortunately, these loads vary with respect to their amount of harmonic content and their response to problems caused by harmonics. The prevalent difficulties with harmonics are voltage and current waveform distortions. In addition, Electronic equipment like computers, battery chargers, electronic ballasts, variable frequency drives, and switching mode power supplies generate perilous amounts of harmonics. Issues related to harmonics are of a greater concern to engineers and building designers because they do more than just distort voltage waveforms, they can overheat the building wiring, cause nuisance tripping, overheat transformer units, and cause random end-user equipment failures. Thus power quality is becoming more and more serious with each passing day. As a result, active power filters (APFs) have gained a lot of attention due to their excellent harmonic compensation. However, the performance of the active filters seems to have contradictions with different control techniques. The main objective of this paper is to analyze shunt active filters with fuzzy and pi controllers. To carry out this analysis, active and reactive current methods (id-iq) are considered. Extensive simulations were carried out. The simulations were performed under balance, unbalanced and non sinusoidal conditions. The results validate the dynamic behavior of fuzzy logic controllers over PI controllers.

A Single Phase Power Electronic Transformer considering Harmonic Compensation in Scott Traction System

Shaodi Ouyang,Jinjun Liu,Xinyu Wang,Shuguang Song,Xueyu Hou,Teng Wu 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

Power electronic transformer(PET) has been the focus of interest in recent years. Compared with conventional low frequency transformers, PETs can offer many additional functions such as phase shifting, frequency shifting and reactive power/harmonic compensation. This paper proposes a single phase PET for the Scott railway power system. The PET achieves active power control which balances the Scott’s secondary currents. The PET also achieves reactive/harmonic compensation. The configuration and control strategy of the proposed PET is discussed. Simulation results from PLECS verifies the effectiveness of the proposed PET and its control strategy.