用于辅助电源Buck变换器的切换滑模控制策略

A Control Strategy of Switching Sliding Mode for Auxiliary Energy Source Buck Converter

针对电动汽车辅助电源系统采用滑模控制方法,存在策略实现复杂度高、系统输出不稳定的问题,提出了一种用于辅助电源Buck变换器的切换滑模控制策略。将辅助电源系统输出电压与目标电压进行对比输出电压误差,然后在限制条件下对电压误差进行调节,有效避免了电压误差变化率的负向输出,从而实现了MOSFET开关的高效控制。搭建仿真模型与实验平台,完成了对切换滑模控制策略有效性的验证,结果表明:所提的辅助电源Buck变换器的切换滑模控制策略在降低复杂度的基础上,能有效地消除奇异问题,保证系统的动态响应速度和稳定性;与传统的滑模控制策略相比,辅助电源采用切换滑模控制策略,系统启动响应调节时间缩短了25%,系统抗干扰能力和鲁棒性均得到了提高。

A switching sliding mode control(SSMC)strategy for auxiliary energy source Buck converter is proposed to solve the problems that the implementation of the sliding mode control(SMC)strategy for auxiliary energy source system in electric vehicle is too complicated,and the output voltage of the system might be unstable.The output voltage and target voltage of the auxiliary energy source are compared to output a voltage error.Then,the voltage error is regulated under some restrictive conditions,so that negative output of the change rate of the voltage error is effectively avoided,and the efficient control of MOSFET switch is realized.A simulation model and an experimental platform are established to verify the effectiveness of the proposed SSMC strategy.Results show that the proposed SSMC strategy for auxiliary energy source Buck converter effectively eliminates the singularity problem and reduces the implementation complexity.Moreover,the dynamic response speed and stability of the auxiliary energy source system with Buck converter are guaranteed.A comparison with the SMC strategy shows that the proposed SSMC strategy has 25%improvement in the settling-time of start-up response for the auxiliary energy source system with Buck converter.The anti-interference ability and robustness of the system are improved.