Research On Three Phase Four Wire APF Based On Simulink

With the continuous advancement of science and technology and Increased automation of power systems,various non-linear loads continuously appear in the power grid,resulting in more and more serious harmonic distortion in the power grid current,deteriorating power quality of the power grid,and even damaging the power equipment.,causing a serious accident.Active power filters can compensate for harmonic components of load currents and are therefore widely used for power grid harmonic compensation.The most commonly used shunt active power filter is a three-phase three-wire system,three-phase four-wire system,etc.Three-phase four-wire active power electronic filters are widely used for current distortion compensation in modern buildings.Based on Simulink software,we will analyze the design of three-phase four-wire active power filter in detail.These studies are important for understanding the working principle,key technologies and design and optimization of three-phase four-wire APF.First,based on the introduction of current distortion and evaluation criteria,we compare the passive power filter and active power filter.In the analysis of active power filter,the topology and working principle of active three-phase power filter are analyzed in detail.The key technologies of the three-phase four-wire shunt active power filter are discussed in detail.The instantaneous power theory is used to extract the command current algorithm to extract the instruction current.By comparing the hysteresis comparator and the triangular wave carrier modulation method,the current tracking algorithm is determined.Triangular wave carrier modulation method is used to track the command current.Traditional PI control algorithm + repetitive pulse control algorithm is selected as the current inner loop control algorithm.Traditional PI control algorithm is selected as the voltage outer loop control algorithm.Secondly,the key technologies of the three-phase four-wire parallel APF system are studied in detail,and Simulink in MATLAB is used to simulate the design scheme.The harmonic currents of system load and are simulated and analyzed in turn.The command current extraction algorithm is simulated.The parameters of the PI control function and the repeated pulse control function are optimized by analyzing the forward transfer function of the APF system.Outer loop voltage control and voltage regulation control parameters are initially determined through simulation.The simulation results based on Simulink show that the three-phase four-wire shunt APF based on PI+ repetitive pulses can compensate the current total harmonic distortion to about 6%.The DC side voltage can be stabilized at 800V to achieve the target。...