Research On The Applications Of Multiple Converter Unified Power Quality Controller In Active Distribution Networks

A large number of different distributed generation make the traditional network more active and automated. A variety of clean energy is made full used in the distributed network(ADN), However, he power quality problems have become increasingly prominent. Increasing power electronic devices and nonlinear loadshave brought some negative effects on the power quality, Make power quality analysis and control issues attracting more and more attention. In the paper, a new structure called Multiple converter unified power quality controller(MC-UPQC) is introduced to solve power quality problems in the distribution network, Analysis basic principles of MC-UPQC and design control strategy for ADN.The structural characteristics of the active distributed network and energy flow control structure are introduced in the paper. From different aspects Analyze adverse effects of DG on the Active distributed network and the propagation and amplification of the effects. The quality power of active distributed network is summarized to lay the application background for MC-UPQCSeveral classic signaldetections are introduced based on the structure of the Multiple converter unified power quality controller, Voltage detection method based on generalized instantaneous power theory and current detectionbased on instantaneous reactive power theory are used in the structure. The control strategy of series active filter of the MC-UPQC utilize voltage hysteresis control with differential negative feedback, the control strategy of shunt active filter of the MC-UPQC utilize current hysteresis control.The main parameters are set according to the main circuit topology of the MC-UPQC. Comparison between hysteresis control strategy and differential negative feedback voltage hysteresis control is made in simulation to show the later strategy is more effective. The performance of MC-UPQC between two lines in distributed network prove that the series and shunt active filter control strategy effectively, but also demonstrated the feasibility of MC-UPQC.