地铁能量回馈NPC三电平变流器的研制

Design of Subway Regenerative Energy Feedback NPC Three-level Converter

地铁能量回馈中点箝位(NPC)三电平变流器的电能质量高、重量体积小,可以将地铁制动时的再生能量回馈到交流电网,极大地节约了电能。首先分析了地铁能量回馈系统的工作原理,然后给出了多模块并联的地铁能量回馈变流器主电路参数与控制策略的设计方法,最后设计了1台额定容量为2 MW,8个NPC三电平模块交直流侧并联的地铁能量回馈变流器,并搭建了RTDS仿真系统,完成了仿真实验,实验结果表明所设计的地铁能量回馈变流器可以满足地铁能量回馈的要求,并且电流谐波小、均流精度高、电容电压均衡度好。

Subway regenerative energy feedback neutral point clamp(NPC)three-level converter has high power quality and small weight and size.It can recover the energy of subway braking to the power grid and save energy greatly.At first,the working principle of the energy feedback system is analyzed,and then the design method of main circuit parameters and control strategy are presented.Finally,a 2 MW rated capacity,8 module in parallel AC/DC side of the subway regenerative energy feedback NPC three-level converter in parallel is designed and the RTDS simulation system is built,the simulation experiment is completed,the experimental results show that the designed subway energy feedback converter can meet the requirements of the energy feedback and has small current harmonic,both high accuracy current sharing and good capacitor voltage balance.