基于FPGA的比例积分滑模控制DC/DC变换器研究

针对DC/DC Buck变换器的动、静态性能要求,从Buck变换器状态方程出发,设计电感电流、输出电压及其积分的线性组合滑模面,并利用该滑模面证明比例积分滑模控制的存在条件及稳定性条件,构建基于FPGA控制的Buck变换器实验平台并加以验证。据此,实现所提出的算法对Buck变换器的控制。理论分析和实验结果表明,所提出的比例积分滑模变结构控制比传统的双闭环PI控制在系统参数变化、供电电压变化以及外部干扰情况下,都具有更好的鲁棒性,具有控制精度高和动态响应速度快的特点。

Design of proportional integral sliding mode controller for DC-DC converter based on FPGA

In order to meet the dynamic and static performance requirements of the DC/DC Buck convert-er,a linear combination of the inductor current,the output voltage and their integral sliding mode surface was designed based on the state equation of the Buck converter,and the existence conditions and stability conditions of proportional integral sliding mode control were proved by using the sliding mode surface ,and the experimental platform of Buck converter based on FPGA control was constructed and verified.Accord-ing to this,the control of the Buck converter is realized by the proposed algorithm.Theoretical analysis and experimental results show that the sliding mode control possesses a better robustness against system parameter variation,power supply voltage variation and external disturbance compared with the conven-tional double closed-loop PI control method,and the converter could get high control precision and fast dynamic response.