Research Of Dividing Frequency Control Strategy For Shunt Active Power Filter

Shunt active power filter is a power electronic device for active harmonic suppression and compensation.In this paper,in order to meet the real-time and accuracy for harmonic compensation of SAPF,that is the problem of Computationally intensive harmonic detection,the problem of Selective harmonic component compensation of compensation issues and the problem of Shunt Active Filter grid problem.In terms of the problem of the large calculation burden of conventional detection method,the improved unity power factor detection method is proposed,The algorithm can significantly reduce the amount of computation,improve real-time performance of detection algorithm,and the impact of the grid voltage distortion does not affect detection results;In terms of the issue of large calculation burden,strong time delay,and multi-variable coupling for traditional selective compensation,dividing frequency control method based on internal model principle is proposed,with a little calculation burden,good real-time performance,less coupling characteristics,and the performance of VPI and PR two resonant controllers are compared,highlighting the VPI controller retains superior performance;For application of VPI controller to the micro-controller or digital signal processor,In terms of the problem of traditional discrete method resonant frequency deviation based on the double integrator,s a new discrete method is proposed,poles and zeros of VPI controller are optimized to better selectivity for digital experiment;For high-frequency ripple problem of SAPF tied to the network,a novel LLCL filter is proposed,the LLCL filter can be directly absorbed SAPF high frequency ripple,for the resonant peak problem of LLCL,RC parallel LLCL passive damping method is proposed,the method is simple and easy to implement,and can improve the network waveform quality when SAPF is tied to grid.Finally,the MATLAB software is used to build a simulation model SAPF,verify key issues raised by this paper,and debugging experiments on the basis of experimental prototype design to achieve better harmonic suppression effect,to verify the feasibility,effectiveness and practicality of the proposed method.