提出了一种新型三相统一电能质量控制器(UPQC)的拓扑结构及其相应控制策略。与传统UPQC相比,它特殊的拓扑设计本身就可避免交流短路和直流电容直通故障,因而无需引入变压器等隔离环节,且仍可保证串并联单元之间的能量流动。基于这种拓扑结构,文中又详细阐述其串并联单元相应的控制策略,使之能够实现传统三相UPQC的各项功能。最后给出PSCAD/EMTDC软件的仿真结果,验证了所提出的拓扑和控制策略的有效性。
This paper introduces a novel three-phase unified power quality controller (UPQC), including its topology and the related control strategies. Compared to the traditional ones, its special topology design can inherently avoid the AC or DC system short circuit, so that no extra isolating circuits, i.e. transformers, are needed and the energy exchange between its series and parallel units can still be ensured. Based on the novel topology, the corresponding control strategies for the series and parallel units are elaborated respectively, which enable the proposed UPQC to achieve such functions as that of the traditional ones. Finally, simulation results using PSCAD/EMTDC are given to verify the validity of the proposed topology and control strategies.