并联型模块化级联超级电容多目标电能质量治理研究

Research on Multi-target Power Quality Management of Parallel Modular Multi-level Cascaded Super-capacitors

为改善10 kV配网侧电能质量,针对传统UPQC与DVR对电压暂降具有补偿深度不够、补偿时间不长等不足,提出了将超级电容储能与模块化多电平变换器拓扑结构相结合,形成并联型模块化级联超级电容储能P-MMC-SCS(parallel-modular multilevel cascaded-super-capacitor storage)多目标电能治理拓扑结构。首先对其主电路拓扑结构进行了分析,然后分别针对电压未暂降时电流补偿分量检测与跟踪及电容均压、电压暂降时电压补偿分量检测与跟踪进行了控制策略研究,根据P-MMC-SCS主电路结构与补偿分量特点采用了PI控制。最后通过在Matlab/Simulink中对P-MMC-SCS仿真研究,结果表明P-MMC-SCS兼具支撑网侧的电压暂降和治理负荷侧电流谐波、无功的功能。

To improve the power quality of 10 kV distribution network and solve the shortcomings of the traditional UPQC and DVR such as insufficient compensation voltage and short compensation time,a topology of multi-target power quality management for parallel-modular multi-level cascaded-super-capacitor storage(P-MMC-SCS)is formulated in this paper by combining the advantages of super-capacitor energy storage with the MMC topology.First,the main circuit topology is analyzed.Then,the control strategy of current compensation component detection and tracking together with capacitor voltage balancing without voltage sag,and that of voltage compensation component detection and tracking with voltage sag,are studied,respectively.According to the main circuit structure of P-MMC-SCS and the compensation component characteristics,PI control is adopted.Finally,simulations of P-MMC-SCS are carried out in MATLAB/Simulink,and results show that it has functions of supporting grid-side voltage sag and managing load-side current harmonics and reactive power.