Research On Compensation Control Strategy Of Parallel Active Power Filter

According to the development of electric and electronic technology, many high powerswitch parts are applied in different kinds of electrical power resource equipment control quicker, more efficient and saving more energy. While these appliances consume active power, as nonlinear loads, harmonics are outputted and active power are consumed. Consequently, the power grid is polluted.Compared with the conventional passive power filters, active power filter (APF) has many advantages, traditional compensating equipments include parallel connected cpacitor and LC filter, can not follow the variety of reactive power for its fixed indepedance which will not meet the demand for quickly compensation to reactive power and harmonics. Active Power Filter is electric-eletronic equipment used to dynamic harmonics suppression and reactive power compensation. The equipment can compensate in real-time to volume and frequency of reactive power and harmonic.This paper introduces the generation, pollution and the harm of harmonics, and the principle of APF, discusses the method of harmonic current detection based on the theory of instantaneous reactive power load. Researches the parallel APF's control strategy, puts forward the PI controller structure based on the fuzzy control, design principles and methods. Finally detects and analyzes the difference of the frequency spectrums of the system before and after the addition of active filter. The result proves the necessary of this APF.