机车动力蓄电池充电机用三电平Buck变换器建模及其控制系统设计

Modeling and Control System Design of the Three-level Buck Converter for Locomotive Power Battery Charger

输出接动力蓄电池的三电平Buck变换器是一个时变、非线性、多模态的动态系统。为简化其控制系统设计,文章详细分析了系统各模态的工作过程,利用状态空间平均法建立了其等效线性模型,并针对简化后的模型设计了一种多闭环控制系统。Matlab仿真结果显示,系统输出电流动态响应快、抗输入电压波动能力强,验证了等效模型的合理性及控制系统设计的有效性。

Three-level Buck converter with output connected to power battery is a time-varying,nonlinear and multi-modal dynamic system.In order to simplify the design of its control system,the working process of each mode of the system is analyzed in detail,its equivalent linear model is established by using the state space averaging method,and a multi-closed-loop control system is designed for the simplified model.Matlab simulation results show that the system has fast output current dynamic response and strong input voltage fluctuation resistance.The rationality of the equivalent model and the effectiveness of the control system design are verified.