Robust Regulation of Oxygen Excess Ratio and Cathode Pressure for PEMFC Air Supply Systems with Centrifugal Compressor

Lingfeng Wang, Lei Wang, Zhiyang Liu, Hongye Su

Abstract: This paper studies robust regulation problem of oxygen excess ratio (OER) and cathode pressure for proton exchange membrane fuel cell (PEMFC) air supply systems with centrifugal compressor. With the speed of the centrifugal compressor and the valve opening degree as control inputs, a robust output regulation problem is formulated for the PEMFC air supply system modelled as a two-input two-output nonlinear control system. To overcome the difficulties of nonlinearities, uncertainties and couplings between input-output channels, we introduce a change of coordinate to transform the original problem into a robust output stabilization problem of a two-input two-output nonlinear system. For such a problem, an “ideal” full-information controller is designed via feedback linearization, based on which an extended-state observer-based control method is proposed, robustly regulating the OER and cathode pressure arbitrarily close to desired values. Simulations are made to demonstrate the effectiveness of the proposed method.