移相全桥变换器双模块并联均流技术的研究

讨论移相全桥变换器双模块并联技术,该技术采用自主均流法实现双模块的电流均流,具有均流精度高,动态响应好,可以实现冗余技术等特点。为了实现双模块自主均流提出了电压环、均流环和限流环三环控制结构,电压环和限流环共用一个PI调节器,均流环使用一个PI控制器。分析均流的整个控制过程,在设计时使电压环与限流环的动态响应速度较快,均流环的响应速度较慢,同时在整个负载范围内使系统有一定的幅值和相位稳定裕度。设计了一台单模块输入母线电压175~320V;额定输出电压220V;额定输出功率5·5kW,整机输出11kW的样机。仿真结果和实验结果表明样机的均流性能良好。

Study on Current-Sharing of Double Modules Parallel Technology for Phase-Shifted Full-Bridge Converter

Double modules parallel technology of phase-s hifted full-bridge (PSFB)converter is introduced. Automatic current-sharing method is appli ed. This method has the advantages: high current-sharing precision, good trans ient response, and implementing redundancy. Three-loop control method of volta ge loop, current-sharing loop and limited current loop is presented. The volta ge loop and limited current loop share a same PI controller. Another PI control ler is used for the current-sharing loop. The principle of current-sharing is analyzed in detailed.The voltage loop and limited current loop has a fast d ynamic performance comparing to the current-sharing loop. The system has large r amplitude and phase margin in whole load range. A prototype with input voltag e DC 175V to 320V, output voltage DC 220V, single module output power 5.5kW, do uble module output power 11kW is designed. The results show the current-shari ng performance of the system is good.