负载换相逆变器电流测量分析研究

Load Commutated Inverter Current Measurement Analysis and Research

通过对燃气轮机负载换相逆变器(LCI)运行工况进行分析,提出LCI系统电流互感器需关注的若干问题。首先,分析了网桥侧电流在零值附近偏移的原因,并对比电流互感器在不同励磁电感及电阻负载下的采样效果,提出了电流互感器的选型及使用建议;其次,针对LCI系统启动初期,机桥侧电流互感器快速饱和的现象,提出了差动保护及控制算法的处理原则。对LCI系统电流互感器设计选型及保护应用有一定意义。

Two kinds of problems in the load commutated inverter（LCI） system are presented.The reason of the inaccurate of zero current sampling on the grid side of the bridge is analyzed, and the sampling effect of the current transformer under different excitation inductance and resistance load is compared, the rules of the selection and application of current transformer is presented.In the initial stage of LCI start-up, considering the phenomenon of the fast saturation of the current transformer on the motor side of the bridge, the processing principle of differential protection and control algorithm is put forward, which is of great significance for the popularization and application of LCI.