Impact Analysis of Frequency Fluctuations on the Performance of Passive Filters in Microgrids

Due to adopting of a large number of power electronic devices, microgrids are often rich in harmonic content, and suffer to serious waveform distortion. The grid frequency also fluctuates along with the load variations or power supply fluctuations. All these factors increase the difficulty of filtering. This paper briefly introduces the microgrids structure, a hybrid filter circuit design and working principle of passive filter. The impact of grid frequency on the performance of passive filter is analyzed and studied in detail and verified with simulation. The study results provide some fundamental guidance for choosing the capacity of active filter when designing the hybrid filter for microgrids.