弓网离线对地铁车辆安全可靠运行带来很大危害。给出了弓网离线的等效过程,得到离线期间地铁车辆弓网系统的等效电路。以某地铁辅助逆变器系统为例进行了离线暂态分析与仿真验证。结果表明,离线引起逆变电路中基波分量大为减小,绝缘栅双极型晶体管IGBT上谐波成分增多,带来耐热、绝缘等方面的隐患,甚至造成逆变器模块损坏,极大地降低了地铁车辆运行的安全性、可靠性。对于IGBT的选型、保护及弓网结构的改进提供了重要参考。 Bow network off the subway vehicle safe and reliable operation has brought great harm. The equivalent process of bow net offline is given, and the equivalent circuit of subway bow net system is obtained. Taking a subway auxiliary inverter system as an example, offline transient analysis and simulation are carried out. The results show that the fundamental component of the inverter circuit is greatly reduced due to the off-line, the harmonic content of the insulated-gate bipolar transistor IGBT is increased, which brings about the problems of heat resistance and insulation, and even damages the inverter module. The earth reduces the safety and reliability of subway vehicles. For the IGBT selection, protection and arch network structure provides an important reference.