重载机车滑模极值搜索最优粘着控制研究

Optimal adhesion control for heavy-haul locomotive based on extremum seeking with sliding mode

为解决因轨面潮湿、雨雪外界条件变化等因素影响轮轨粘着特性而导致重载机车牵引力不能有效发挥的问题,提出一种基于滑模极值搜索的超螺旋滑模最优粘着控制算法。首先建立重载机车动力学模型;然后根据极点配置法设计全维状态观测器实时估计轮轨粘着系数,采用滑模极值搜索算法实时搜索出变化轨面的最佳蠕滑速度,并应用微分跟踪器跟踪最佳蠕滑速度导数;进而采用超螺旋滑模控制算法设计控制器使重载机车运行于最佳粘着点附近。仿真结果与传统滑模控制相比,粘着系数搜索到实际最优值的时间提前10 s,转矩误差保持在3%内;所提出的控制方法能够快速搜索到不同轨面下的最佳蠕滑速度,实现了重载机车的最优粘着控制。

In order to solve the problem that the traction force of heavy-haul locomotive can’t effectively play the role due to external conditions change such as humidity,rain and snow,drying that led to adhesion characteristics between wheel and rail,an optimal adhesion control strategy based on sliding mode extremum seeking algorithm is proposed in the paper. Firstly,the dynamic model of heavy-haul locomotive is established. Then,the full state observer is designed according to the pole assignment method to observe the motor load torque in real time,the sliding mode extremum seeking algorithm is used to search the optimum creep velocity of the track surface in real-time,and the differential tracer is used to track the derivative of the optimum creep speed estimation value. And then super-twisting sliding-mode control method is designed to control the heavy-haul locomotive running near the optimum adhesion coefficient point. Compared with the traditional sliding mode control,the simulation results show that the time of adhesion coefficient searched to the actual optimal value advances 10 s,and the error of torque control is within 3%. The proposed control method can quickly search the optimal creep speed under different rail surfaces,and optimal adhesion control of heavy-haul locomotive is realized.