Robust Control of Contact Force for Pantograph-Catenary System

To improve the quality of the current collection transmitted to a high-speed train, based on a pantograph model with a three-degree of freedom, two methods are presented to suppress the vibration of the pantograph-catenary system. One is H
_∞
robust control, and the other is improved equivalent-input-disturbance (IEID)-based control. For the H
_∞
robust control, a robust stability condition together with a performance criterion in the frequency domain is given to obtain a dynamic controller. For the IEID-based method, the LQR regulation combined with LMI technique and Lyapunov stability theory is used to design the control gains of the state-feedback controller, the state observer and the IEID estimator in the time domain. Simulations show that these two methods achieve good vibration suppression performance in the steady state.