基于多抽头变压器的动态电压补偿系统拓扑及控制策略OA

[Objective]To address the issues of high cost in traditional high-capacity dynamic voltage restorer(DVR)and the difficulty of multi-tap transformer(MTT)in achieving precise compensation for grid voltage sags,a topology of dynamic voltage compensation system(DVCS)based on MTT and its voltage compensation strategy are proposed.[Methods]By designing a composite control strategy and formulating transformation ratio rules to control the on-off states of fast-action switches,the DVCS can operate in either direct compensation mode or indirect compensation mode under different operating conditions.In the direct compensation mode,only the converter module compensates for the load voltage deficit;whereas in the indirect compensation mode,the MTT and the converter module work together to maintain load voltage stability.[Results]By utilizing switch-based control to coordinate the transformer and converter,the DVCS maintains stable load voltage under conditions of a 20%voltage boost or a 70%voltage sag.Furthermore,this topology reduces the converter's rated capacity by 50%and lowers the overall cost by over 10%.[Conclusions]The proposed DVCS can meet both the compensation capacity and accuracy requirements in engineering applications while maintaining the dynamic stability of the load voltage amplitude,demonstrating a significant cost advantage.