Application Research On Shunt Hybrid Active Power Filter (SHAPF)

It is difficult for active power filter to use in the high-voltage power system because ofthe limitation on the capacity and voltage-level of the switching devices. Shunt hybrid activepower filter (SHAPF) with the advantages of passive filters and active power filter can beapplied in high-voltage power system, which is a research focus on the harmonic suppressionand reactive power compensation nowdays. In this thesis, SHAPF is studied in the range ofengineering theory and practical application. Main contents are as follows:1、SHAPF is designed for three rolling substation 10kV-1 in Tianjin Pipe (Group)Corporation, which is suitable for existing high-voltage power distribution system in thisthesis. And compensation current fluctuation coefficient is defined and compensationperformances are analysed and simulated under three different control parameters. The resultsshow that the load current caused by non-linear load and DC voltage fluctuation of inverterare larger influential factors of its compensation performance. Then SHAPF control mustbalance the tracking control of harmonic currents and DC voltage control.2、The instantaneous reactive power theory and the harmonic and reactive currentconventional detection method based on the theory is introducted. And its shortcomings arepointed out in this thesis. Then a three-phase system harmonic and reactive current detectionmethod improved is proposed, which combines the instantaneous reactive power theory andcoordinate projection principle and overcomes the limitations of the traditional detectionmethod. And the improved detection method can accurately get the harmonic and reactivecurrent component in the voltage waveform asymmetry and distortion system in real time.3、According to the topology of three-phase three-wire SHAPF, its state-space model isestablished，which is a general dynamic model in practice. The principle of linear autodisturbance rejection control technique (LADRC) is detailedly introducted in this thesis. Anda linear auto disturbance rejection controller based on the state-space model is designed,including current tracking controller and DC voltage controller. All the uncertain dynamicsand the external disturbance are regarded as an integral disturbance, which can be observedand compensated in this controller to achieve DC voltage control and instruction current trackin real time. That results in better adaptability of the whole system in the work area.4、SHAPF is applied in three rolling substation 10kV-1 in Tianjin Pipe (Group)Corporation. According to the characteristics of 10kV-1 and the harmonics, the parameters ofSHAPF are designed and the overall system is simulated and analyzed in this thesis. Thedigital simulation result shows that SHAPF designed with good compensation performancecan real-timely and reliably track harmonic current system and can significantly improve thesystem current wave. This is a theoretical basis for SHAPF engineering applications.