高速发电机用宽电压范围双管Buck-Boost变换器暂态稳定分析与系统校正

高速永磁发电机宽速度范围运行时输出电压波动大,当发电机输出端接双管Buck-Boost变换器进行调压时,宽电压范围输入对变换器的稳定性和动态性能提出挑战。本文采用平均开关法建立了双管Buck-Boost变换器电感电流连续的非理想小信号模型,基于该模型分析了占空比、负载、输出滤波电容等效ESR、控制参数等对系统暂态稳定性能的影响,给出了提高系统暂态性能的控制参数设计方法。分析研究发现:占空比的变化导致系统的非最小相位反应明显,系统的动态响应变差;负载变化时系统的动态响应变化小;增大输出滤波电容等效ESR可以改善系统的动态性能。仿真和实验结果验证了暂态稳定分析和控制参数设计的合理性。

Transient analysis and system compensationof two-switch Buck-Boost converter for high-speed generator with a wide voltage range

The output voltage range of high-speed permanent magnet generator is wide .As two-switch Buck-Boost ( TSBB ) converter is used in the output of the generator to regulate the DC voltage ,the wide input voltage range will challenge the stability and dynamic performance of converter .The low-frequency small-signal models of TSBB converter which works in the continuous conduction mode ( CCM) were built by averaged switch model.The influence,such as the duty ratio,load,equivalent series resistance(ESR) of output filter capacitor and the right half plane ( RHP) zero on the transient stability of control system was analyzed separately .The method of control parameter design to improve transient performance was given.When duty cycle changed ,the reaction of non-minimum phase system was obvious ,and the dynamic response of the system became bad .The dynamic response of the system caused by different load varia-tions changed little .ESR of filter capacitor can effectively improve the dynamic performance of the sys -tem.Finally,the transient analysis and control design parameters rationality are verified by the simulation and experimental results .