MMC-STATCOM在变电站应用中的研究

Research on MMC-STATCOM in Substation Application

以某变电站实际工程为背景,研究了基于模块化多电平变换器(modular multilevel converter,MMC)的静止无功补偿器(STATCOM)的拓扑结构及无功补偿原理。根据系统的实际情况,分析了MMC-STATCOM主要的控制目标是维持母线电压稳定和恒无功控制。当母线出现快速和大幅度电压变化时,本文所提出的MMC-STATCOM能够迅速提供无功电压支撑,维持母线电压的稳定;当系统需要补偿无功功率时,MMC-STATCOM也能够迅速跟踪目标电流的变换。最后,以某电站工程数据为依据在电力系统分析综合程序(PSASP)中进行了仿真研究,仿真研究表明:STATCOM的控制功能设计合理,能够对系统无功变化作出快速响应,能有效实现电压支撑作用,提高电网的输电能力,保证电网的安全稳定运行。

This paper mainly researches the static synchronous compensator（STATCOM） based on modular multilevel converter（MMC） on the background of one substation, and analyzes its topology structure and reactive power compensation theory. The main control aims of MMC-STATCOM are to maintain bus-voltage stabilization and constant reactive power control. The MMC-STATCOM can quickly provide the reactive power to maintain bus-voltage stabilization when a sudden change in bus voltage. The MMC-STATCOM also can rapidly track the aimed current change when needing compensate reactive power. Finally, simulation results in PSASP verify that the proposed MMC-STATCOM not only has a fast dynamic response, but also can effectively support bus-voltage, which improves the transfer capability of power grid and ensures the safety and stability operation of network.