Design And Realization Of Shunt Active Power Filter

With the modernization of industry, especially large scale application of modern power converter equipment and the content of harmonic current in the power network increases gradually, decrease in power factor and exacerbate the power network. APF is considered as one of the most effective solutions to improve power pollution. It can compensate harmonic of which frequency and amplitude is variable and the compensating characteristic is free of infection of the impedance in the electrical network. The good filter character of APF can satisfy the needs of compensation, so it has been widely researched and developed in the recent years.Firstly, the dissertation introduces the background, present situation and developm- ent trends of APF. According to the different storage devices, topology structure, and the number phase of circuit. For grid harmonic component testing methods and the control strategy are described in detail.Secondly, introduce the topology structure and the selection parameter of main circuit and the selection of out filter of shunt active power filter .Design and completed the control system which is based on DSP (TMS320F2812). Build and debug minimum system based on DSP, sampling circuit for current and voltage, drive circuit and protect circuit of IPM and crossing zero sampling circuit, etc. Enhance the stability of the system. In the actual engineering realization for the elimination of main circuit to control circuit, In order to eliminate the main circuit greatly interference the control circuit through the current signal single twisted-pair grounding mixed twisted-pair grounding method.Thirdly, frequency and real-time of inverter driving pulse has great influence in compensation effects of system that can be observed through the simulation. In order to further improve the harmonic compensation effect of active power filter, Increased the frequency, adopts the mode of interlaces the optimized for real-time of a current-measure for harmonic component and the control strategy. Increased the frequency of impulse control.Finally, the experimental results under low-power conditions show that the device has a good performance of real-time detection and accurate compensation.