以无工频变压器牵引传动系统前端的单相级联H桥整流器(CHBR)为研究对象，构建了其数学模型，在电压电流双闭环控制策略的基础上，引入无锁相环技术，改进瞬态电流控制策略。实现了系统发生扰动时，网侧电流对电压相位频率的快速精确追踪。进一步地，对传统附加平衡电压控制策略加以改进，增加模糊控制技术，解决了CHBR在非理想电网或负载大范围投切载时，存在的直流侧各级电容电压不平衡、压差大等问题。最后，利用MATLAB/Simulink进行仿真，对所提策略在CHBR运行时的快速响应和抗干扰能力进行了验证。

A single-phase cascaded H-bridge rectifier (CHBR) in the front end of the traction drive system of a transformer without power frequency is studied, and its mathematical model is constructed. On the basis of the voltage and current double closed-loop control strategy, the non phase-locked loop technology is introduced to improve the transient current control strategy. The grid-side current can quickly and accurately track the voltage phase frequency when the system is disturbed. Furthermore, the traditional additional balanced voltage control strategy has been improved, and the fuzzy control technology is added to solve the problems of unbalanced voltage and large voltage difference between all levels of capacitors on the DC side of CHBR when it is not ideal power grid or load is switched over a wide range. Finally, MATLAB/Simulink is used for simulation to verify the fast response and anti-interference ability of the proposed strategy during CHBR operation.

辽宁省交通科技项目（202243）