柔性直流输电换流器经济性分析

Economic Analysis of Converters Used in Flexible HVDC

本文通过分析IGBT直接串联两电平电压源换流器(2L-VSC)和模块化多电平换流器(MMC)的经济性差异,为特定工作条件下柔性直流输电系统换流器的选型提供理论依据。对比了两种换流器的结构差异,详细分析两种换流器的主电路器件参数设计方法和损耗计算方法,在此基础上提出了合适的换流器经济性评估指标,对IGBT直接串联两电平换流器和模块化多电平换流器的经济性进行定量对比分析。结果表明在35kV及以下工作场合,IGBT直接串联两电平换流器比模块化多电平换流器经济性更好。

Economic performance is an important indicator for evaluating the performance of power equipments under the same working conditions. In order to analyze the eco- nomic differences between the two-level voltage source con- verter with direct series IGBTs and modularization multi-lev- el converter （MMC）, and to provide theoretical basis for se- lecting the type of converter for flexible HVDC in a specific working condition, the parameter design method of main circuits devices and the loss calculation approach for two kinds of the converters are analyzed, based on which the ap- propriate economic indicators are proposed and the econom- ic performance of the converters are assessed and compared quantitatively. The results show that the economy of converter with direct series IGBTs is better in the condition of AC voltage being 35kV and below.