针对常见的滑模控制方案应用于DC/DC开关变换器中存在的问题,将基于积分重构的滑模控制方案用于连续导电模式下的Buck变换器输出电压校正,该方法只需反馈输出电压和开关位置,省略测量电感电流。给出了采用积分重构建立的滑模切换面的滑模存在区域和相平面上吸引区,通过基于平衡点的线性化小信号稳定性分析得到局部渐近稳定的充分条件。仿真和实验结果表明,此方法具有良好的启动性能和动态特性以及对负载大幅度突变具有稳定鲁棒性。
The usual sliding mode control schemes for DC/DC converters and the problems in practical implementations are presented. Sliding mode control scheme based on integral reconstructors is developed for the output voltage regulation of the buck converter in continuous conduction mode. The control method uses only the feedback of output voltage and switch position. The inductor current measurement is omitted and the circuit is simpler. The existence condition of sliding mode in switch surface and the reachable domain in phase plane for the sliding mode control based on integral reconstructors are derived. The local asymptotical stable sufficient condition is obtained by small signal stability analysis based on linearization about the equilibrium point. Simulation and experimental results show the robustness to large load variations, good startup characteristic and dynamics.