This paper presents a novel synchronous reference frame based (SRF) control strategy for shunt hybrid active power filter (SHAPF). The control strategy includes a direct current control (DCC) and an indirect current control (ICC) strategy. SHAPF can achieve harmonic compensation and dynamic reactive power compensation with the proposed controller.
In this proposed method, as distinct from studies in literature, dynamic reactive power compensation and dc link voltage control is realized with ICC and harmonic current compensation is realized with DCC. Also, the proposed controller provides a variable SHAPF dc link voltage which is adjusted according to the reactive power compensation requirements in order to decrease the switching losses of converter and achieve power savings. The performance of proposed controller is verified with experimental results.
- Active Power Filter (APF)
- Reactive Power Compensation
- Direct Current Control
- Indirect Current Control
Fig. 1. Power Circuit Diagram of SHAPF
EXPECTED SIMULATION RESULTS:
Fig.2. Reactive Power Trend (a) and Current Harmonic Spec. (b) of Case I
Fig.3. Reactive Power Trend (a) and Current Harmonic Spec. (b) of Case II
This paper presents a SRF based controller approach for SHAPF. In proposed control method, DCC strategy is preferred for harmonic compensation control to maintain superior dynamic and steady state performance on the compensation of low order harmonics. ICC strategy is used for the reactive power compensation controller and the dc link voltage controller to simplify the controller and provide a successful performance without being affected by dynamic changes in active and reactive current components.
Additionally, the dc link voltage is determined with adaptive to the reactive power demand of load by the proposed control method. By the help of this ability, the switching losses of SHAPF is decreased by keeping only required voltage level on dc link. The proposed control method is applied on the laboratory prototype of SHAPF. The steady state and dynamic performance of controller is verified with the experimental results.
 H. Fujita and H. Akagi, “A practical approach to harmonic compensation in power systems-series connection of passive and active filters,” IEEE Trans. Ind. Appl., vol. 27, no. 6, pp. 1020–1025, 1991.
 H. Akagi, “Active and hybrid filters for power conditioning,” ISIE’2000. Proc. 2000 IEEE Int. Symp. Ind. Electron. (Cat. No.00TH8543), vol. 1, 2000.
 H. Fujita, T. Yamasaki, and H. Akagi, “A hybrid active filter for damping of harmonic resonance in industrial power systems,” IEEE Trans. Power Electron., vol. 15, no. 2, pp. 215–222, Mar. 2000.
 S. Srianthumrong and H. Akagi, “Medium-voltage transformerless ac/dc power conversion system consisting of a diode rectifier and a shunt hybrid filter,” IEEE Trans. Ind. Appl., vol. 39, no. 3, pp. 874–882, May 2003.
 R. Inzunza and H. Akagi, “A 6.6-kV Transformerless Shunt Hybrid Active Filter for Installation on a Power Distribution System,” IEEE Trans. Power Electron., vol. 20, no. 4, pp. 893–900, Jul. 2005.