The Simulation And Application Research Of Shunt Active Power Filter

With the development of power electronics technology,the technology has penetrated into the fields of today's society,but its nonlinear characteristics make the power quality problem in power system become more and more prominent.Therefore,research and development of technology to improve the quality of power has gradually been taken seriously.Active power filter is a new type of power electronic device for dynamic compensation.It not only overcomes the shortcomings of traditional passive filter,but also can effectively compensate for the harmonics of frequency and size change.Firstly,the active power filter under different classifications is analyzed and compared,and the shunt three-phase active power filter suitable for distribution network is chosen as the research object.By analyzing the basic principle of compensation and mathematical model of shunt active power filter,several kinds of harmonic current detection algorithm and compensation current tracking control method are analyzed and compared.Finally,the-p qi i harmonic detection method and the space vector hysteresis control are used as the compensation current control method.Secondly,the L and LCL filters using as the output filter of the active power filter are compared and analyzed,and the selection formula of the parameters of the LCL filter are derived.On this basis,proposing the design of the active damping LCL filter based on the Kalman observer,and compared with the passive damping LCL filter,showing its superior damping effect and low loss.Thirdly,the simulation model of shunt active power filter is built in the Maltab/Simulink simulation software,and the simulation modules described in the second and third chapters are introduced and built.The simulation results show that the active damped LCL filter based on Kalman observer can improve the dynamic performance of the system and analyze the factors that affect the accuracy of its estimated signal.Finally,aiming at the problem of phase shift delay when the active power filter is started,the improvement measures of using the Kalman filter instead of the low pass filter is proposed,which verifies the feasibility of the active power filter design.Finally,different compensation schemes are proposed for the three-phase imbalance in a distribution transformer station area,and the different compensation schemes of the distribution system are simulated and the optimal compensation scheme is selected.The rationality of the selected compensation scheme is verified by the actual feedback data collected in the field.