在瞬时无功功率理论的基础上分析三相三线制电网内在规律,设计了一种新型的数字低通滤波器,克服了数字滤波器的跟随性差的问题。同时用实验仿真分析了该滤波器的正确性和可行性。 Based on the theory of instantaneous reactive power, the inherent law of three-phase three-wire power system is analyzed, and a new type of digital low-pass filter is designed, which overcomes the problem of poor followability of digital filter. At the same time, the correctness and feasibility of the filter is analyzed by experiments.