基于欠压判定的斩波串级调速逆变保护优化  

Inverter protection optimization of chopper cascade speed regulation based on under-voltage criterion

作　　者：王兴武[1,2] 林永君 王兵树[1] 张照彦[2] Wang Xingwu;Lin Yongjun;Wang Bingshu;Zhang Zhaoyan(Department of Automation,North China Electric Power University,Baoding 071003,Hebei,China;Baoding Sinosimu Technology Co.,Ltd.,Baoding 071051,Hebei,China)

机构地区：[1]华北电力大学自动化系,河北保定071003 [2]保定华仿科技股份有限公司,河北保定071051

出　　处：《电测与仪表》2020年第2期141-146,共6页Electrical Measurement & Instrumentation

基　　金：国家自然科学基金面上项目(51876064)

摘　　要：斩波串级调速系统在高占空比运行时转差功率很小,发生逆变故障后的逆变直流电流波形呈现稀疏脉冲形状,导致现有的逆变保护不能检测到故障信号并执行保护动作,极易损坏逆变侧器件。针对现存问题,通过分析斩波串级调速系统在高占空比运行时的稳态电流特性及逆变故障暂态过程,得出逆变保护失效原因的理论依据,并据此进行保护优化,提出带直流回路电压检测及欠压判定的优化方案。仿真及样机实验结果表明理论分析正确,经优化的逆变保护策略能够在逆变故障时有效保护逆变侧器件,可提高系统可靠性。The slip power of the chopper cascade speed regulation system is very small at high duty ratio. The DC current waveform of the inverter presents sparse pulse shape when inverter fault occurs,which results in that the current inverter protection cannot detect the fault signal and perform the protection action,and it easily leads to the damage of inverter side devices. Aiming at the existing problems,the theoretical basis of inverter protection failure is obtained by analyzing the steady-state current characteristics and the transient process of inverting fault at high duty ratio. The protection optimization is carried out,and the optimal scheme of voltage detection and under-voltage criterion with DC circuit is put forward.The simulation and experiment results show that the theoretical analysis is correct and the optimized protection strategy can effectively protect the inverter side devices and can improve the system reliability.

关 键 词：斩波串级调速 逆变故障 保护优化 欠压判定 

分 类 号：TM85[电气工程—高电压与绝缘技术]