基于自适应模糊滑模的列车精确停车制动控制算法

针对高速列车自动驾驶系统精确进站停车问题,基于列车动力学模型和列车制动系统模型,设计1种自适应模糊滑模控制器,通过模糊切换以补偿列车运行过程中受到的基本阻力、线路附加阻力以及外部未知随机扰动等非线性扰动的影响。根据滑模控制理论,利用列车运行过程中的状态偏差,设计基于跟踪误差的等效控制器,以求解列车制动等效控制量;考虑外部扰动,基于优秀司机驾驶经验的模糊推理规则,设计切换控制器,以得到精确控制量。采用本文控制算法对列车制动过程进行仿真验证,并与传统的PID控制和基于指数趋近律的滑模控制进行对比。结果表明:在考虑附加阻力和外部扰动情况下,自适应模糊滑模控制器能够柔化非线性切换控制信号,削弱滑模控制固有的抖振现象,实现对参考轨迹的精确跟踪,并最终实现精确停车;即使在列车制动系统实际控制输出出现偏差时,设计的控制器仍能控制列车精确跟踪参考制动曲线。

Braking Control Algorithm for Accurate Train Stopping Based on Adaptive Fuzzy Sliding Mode

To solve the accurate train stopping problem in the automatic driving system of high speed train, an adaptive fuzzy sliding mode controller was proposed based on the train dynamic model and braking system model. Fuzzy switching was applied to compensate the nonlinear disturbances during train operation process, such as basic resistance, additional resistance and unknown exterior random disturbances. According to the sliding mode control theory, an equivalent controller was designed based on tracking error by using the state deviation during train operating process to solve the equivalent control of train braking. Considering the exterior disturbance, a switching controller was designed on the basis of fuzzy inference rules depending on excellent driving experience to achieve the accurate control. The proposed algorithm was applied to simulate and verify the train braking process, and compared with the traditional PID control and sliding mode control based on exponential approach law. Results show that, considering the additional resistance and exterior disturbances, the adaptive fuzzy sliding mode controller can soften the nonlinear switching control signal, weaken the inherent chattering phenomenon of sliding mode control, achieve precise tracking of reference trajectory and realize accurate stopping finally. Even when the actual control output deviates in train braking system, the designed controller can still control the train to track the reference braking curve accurately.