全半桥混合MMC启动特性研究及实验验证

Research on Start-up Characteristics of Full Half Bridge Hybrid MMC

目前,对模块化多电平换流器(MMC)的启动特性研究主要集中在半桥MMC的启动方法的研究与分析,未对全半桥混合型MMC启动过程进行过多分析。从全半桥混合型MMC的基本结构及交流侧不控充电的原理出发,详细分析了换流器启动过程中直流侧的电压及功率模块电压。提出了一种全半桥混合MMC启动方法。在PSCAD/EMTDC中搭建了全半桥混合型MMC充电仿真模型,对全半桥混合型MMC的充电过程进行仿真研究,仿真研究结果在±10 kV混合型换流阀样机实验中得到了验证。

At present,the research on the start-up characteristics of modular multilevel converter(MMC) mainly focuses on the research and analysis of the start-up methods of half bridge MMC.Excessive analysis is performed during the start-up process of the full half bridge hybrid MMC.Starting from the basic structure of the full half bridge hybrid MMC and the principle of uncontrolled charging on the AC side,the DC side voltage and power module voltage during the start-up of the converter are analyzed in detail.A starting method of the full half bridge hybrid MMC is proposed.The charging simulation model of full half bridge hybrid MMC is built in PSCAD/EMTDC,and the charging process of full half bridge hybrid MMC is simulated.The simulation results are verified in the±10 kV hybrid converter valve prototype experiment.