Robust Adaptive Contact Force Control Of Pantograph-Catenary System: An Accelerated Output Feedback Approach

Pantograph-catenary system plays a crucial role in electrical power collection during the operating process of high-speed trains.Meanwhile,continuity and smoothness of the contact between pantograph and catenary is one of the key factors ensuring high quality power collection,which is essential for the safety and reliability of train operation.Therefore,it is of great significance to conduct a systematical research on the control of the contact force between pantograph and catenary.The contact force is composed of the static force and the dynamic force,the magnitude and stability of which depends on the running speed of the train and vibration behavior caused by external disturbances.With the continuous progress of science and technology and the continuous development of social productivity,the speed of trains has increased significantly.The vibration of the train body becomes more and more obvious,which has a negative impact on the contact force between the pantograph and the overhead line of the high-speed train.If not controlled properly,it may result in very serious consequences.Regarding the above issue,this paper aims at improving the smoothness and continuity of the contact force by using active control.The main research work can be summarized as follows:(1)The article first analyzes the working principle of pantograph catenary system,and introduces different types of pantograph and catenary models and coupling models.Based on the kinematics theory,the physical model of the pantograph-catenary system was introduced and the dynamic equations were derived.At the same time,the characteristics of non-linearity,uncertainty and external disturbance of the bow-net system in reality are fully considered and a binary nonlinear coupling mathematical model is established,which is further converted into a standard type.(2)Based on the established pantograph-catenary model,a robust adaptive control algorithm with simple structure and low cost is proposed,and both modeling uncertainties and external disturbances are taken into account in control design.The appropriate Lyapunov function is selected to prove the stability of the proposed control algorithm theoretically.Moreover,numerical simulations are conducted through MATLAB to verify that the proposed control is able to ensure continuous and smooth contact between pantograph and catenary,and it is robust to nonlinear,unknown time-varying system parameters and external interferences.(3)A rate function is further proposed and designed.By integrating the rate function into the adaptive control,the proposed control scheme ensures the tracking error of the contact force to converge with an accelerated and pre-specifiable decay rate without changing other control parameters.In addition,its effectiveness is verified by both theoretical analysis and MATLAB numerical simulation.(4)Considering that the internal state variables of pantograph-catenary system cannot be directly obtained as a high-order system in practice,an output feedback accelerate robust adaptive control algorithm is designed.The technique of high-gain observer is utilized in control development,which allows the control to be implementable with only output information of the system,and it can complete a good tracking control of the contact force between pantograph and catenary.Both theoretical and numerical simulation verifications are carried out,and in MATLAB simulation verification,the control effect is compared and analyzed with traditional algorithms.