Reasearch On The Single-phase Shunt Hybird Active Power Filter Based On The Instantaneous Reactive Power Theory

The harmonic current pollution from the application of nonlinear loads and current converting equipments badly affects the power system.Therefore,it is urgent to solve the problem by eliminating the harmonic.The instantaneous reactive power theory raised in 1980s gives an effective way to harmonic current detecting.For the shortcoming of LC filters being more and more serious and the technology of power electronic developing very rapidly,eliminating harmonic dynamically by using Active Power Filters(APFs) becomes an important methord.So the research on Active Power Filters is of great importance.The paper first briefly introduced the harmonic causes and hazards,and then introduced the domestic and foreign's situation on harmonic study.Again analysied and classified disscused on the active power filter technology while studied on the instantaneous reactive power detective method.Secondly,by way of widespread investigation and study to the domestic and foreign's technologies and analogy the active power filters,and analyzied the principles of work,merts and shortcomings of these technologies,based on the abosorption of these technologies,it designed a single-phase shunt hybrid active power filter.Through the module of the power system-SimPowerSystemBlockset with Matlab/Simulink,set the parameters and did the dynamic simulation.The results of simulation showed that the active power filter can well control harmonics in a single-phase power system.In this paper,adopted instantaneous reactive power method on single-phase circuit for harmonics detetion,combined with shunt hybrid active power filter for harmonics control,simulated and researced with the diode rectifier as the load power system.Espeically,by way of studying on the low-pass filter in the part of detection, compare with several cut-off frequencies,several orders and several types of filters, get the best result of using the Butterworth-type filter with the 2-order and cut-off frequency of 20 Hz.In the part of current follow-up control circuit,designed the method of compare of instantaneous values in timing control.The method has the advantage of simple circuit,fast response and good current tracking.Compare of passive filter and single-phase shunt active filter,simulation results showed that the part of designed could work feasibily and effective.And it could control harmonics and reactive power compensation very well.