Research On The Respective Control And Compensation Of Three-phase Voltage For Unified Power Quality Conditioner

With the development of power electronic technology and emergency of much non-linear load in power system,the power quality has been more and more deterioration.At the same time,customers' requirements on the quality and reliability of electrical power supply grow higher and higher.Unified Power Quality Conditioner used in three-phase four-line system can effectively compensate multiple different power quality interferences originated either from the load side or from the line side,improve the reliability and quality of power supply.A topological structure and control strategies of Unified Power Quality Controller are introduced,and then a new topology of UPQC in three-phase four-line,which is presented by our team,is used,and the Compensation Principle of UPQC and mathematical model of the series part in UPQC are analyzed in this dissertation.This dissertation focuses on the study of Detection Method of Voltage distortion and the Control Strategies.Then the Detection Method of Voltage distortion based on Park Transforms is chose,and the advantage and disadvantage of different PWM control methods is analyzed in this dissertation.Three-phase four-line system simulation model of the series part in UPQC is constructed with MATLAB/Simulink software for different voltage in the power distribution system.And simulation results demonstrated that the proposed Detection Method of Voltage distortion is correct and valid.This dissertation designs hardware the parameters of series part in UPQC, including the main circuit,driver circuit and the acquisition circuit,and optimizes the choice of the parameters combination with simulation.Then the digital control system based on DSP TMS320F2812,the hardware circuits of the series part and control program written in C in UPQC have been designed and tested.Finally the experiments about three-phase voltage respective control and compensation of the series system in UPQC have been done,and the experiment waveforms and the experiment results are showed and analyzed.