【摘要】 为了增强电动汽车车载电源对负载扰动的鲁棒性,有效抑制系统输出电压的过冲,将一种改进的滑模控制策略应用于电动汽车车载电源控制系统中。为减少系统开关损耗,提高系统效率,车载电源采用LLC谐振变换器拓扑结构。利用扩展描述函数法建立LLC谐振变换器的非线性模型,并在此基础上设计滑模控制方法。选取全局积分滑模面,通过动态的非线性滑模面,设计了整个运动过程中的滑动模态运动,显著地改善了对负载扰动的动态响应。通过仿真和实验证明了所提出的滑模控制策略有效解决了传统PI控制器在负载扰动较大情况下输出电压过冲过大的问题,提高了电动汽车车载电源控制系统动态品质。更多还原

【Abstract】 Aiming at the application of LLC resonant converter in electric vehicles,a sliding mode controller is proposed to improve the robustness of load disturbance and restrain the output voltage overshoot of the system. In order to improve the efficiency of the system,the LLC resonant converter used in the vehicle power supply reduced the switching loss of the system. The nonlinear model of LLC resonant converter was established by means of extended description function method. On this basis,a sliding mode control method was designed. The sliding mode motion of the whole motion of the system was realized by selecting the appropriate global integral sliding surface,and the dynamic quality was improved significantly by using the dynamic nonlinear sliding surface. Simulation and experiment show that the proposed controller can restrain the overshoot of the system more effectively than the conventional PI controller.更多还原