考虑寄生参数的移相全桥变换器恒压恒流自切换控制

Automatic Switching Control of Constant Voltage and Constant Current for Phase-Shifted Full Bridge Converter Considering Parametric Parameters

由于电解、电镀等电化学加工过程中负载变化范围比较大,电化学电源一般需要具备恒压、恒流功能;此外,对于低压大电流电化学电源,电路寄生参数对控制系统的影响较明显。为此,以移相全桥变换器型低压大电流电化学电源为研究对象,建立了考虑寄生参数的移相全桥变换器的高阶小信号模型,分析了电路寄生参数对控制系统的影响;然后给出了高阶小信号降阶方法,以简化控制系统的设计,并在此降阶模型基础上设计了恒压恒流自切换控制系统,保证了系统在负载大范围变化情况下稳定工作。最后制作了一台15V/2000A/30kW的样机,实验证明了此控制方法的可行性。

Constant voltage and constant current control are usually required in the electro-chemical power sources, for large change range of the load in the electro-chemical processing operations. Further, the parasitic parameters in the main circuit have considerable influence on control system in the low-voltage high-current electro-chemical power sources. Therefore, a low-voltage high-current electro-chemical power sources based on phase shined full bridge （PSFB） converter was discussed, the high-order small signal model of PSFB converter with considering parasitic parameters was built, and how the parasitic parameters could affect the performance of the system was analyzed. Then, automatic switching control system of constant voltage and constant current, which could stabilize the system under large change range of the load, was designed based on the reduced-order model of the high-order one. At last, one power supply （15V/2000A/30kW） was built up and performed to verify the validity and reliability of the control method proposed.