Parameter estimation and control of a fuel cell air supply system based on an improved extended state observer

ABSTRACTTracking control of the oxygen excess ratio (OER) and keeping the cathode air pressure relatively stable are essential for the operation of polymer electrolyte membrane fuel cell (PEMFC). In automotive fuel cell air supply systems, the cathode air pressure and OER are usually unmeasurable parameters, which makes the air supply system control and fault analysis very difficult. To solve this problem, this paper proposes an extended state observer based on the hyperbolic tangent function (HTF-ESO) to estimate the cathode air pressure of the fuel cell gas supply system, and indirectly obtains the OER according to the estimated cathode pressure, and designs the sliding mode control (SMC) and a first-order active disturbance rejection control (ADRC) for the tracking control of the OER. The simulation results show that the improved HTF-ESO effectively mitigates the initial differential peak phenomenon and reduces the initial estimation error of the cathode air pressure, and the RMSE of the cathode pressure and supply manifold pressure observation errors are reduced by 68% and 20%, respectively, compared with the present unimproved ESO. Compared with the PI, the RSME of the control error after convergence of the designed SMC and ADRC is reduced by 4.3%, and the OER can be restored to the reference value within 1 second, with good dynamic response.KEYWORDS: Polymer electrolyte membrane fuel cellextended state observercathode pressure estimationoxygen excess ratio tracking controlair supply system AcknowledgementsThis work was supported by National Nature Science Foundation of China (Grant No.51965008); Guizhou Provincial Science and Technology Projects ([2022]045); Technology innovation talent team of Guizhou, China (CXTD [2022]009).Disclosure statementThe authors declare that they have no known potential conflicts of interest.Data availability statementSharing of data is not relevant to this article.Additional informationFundingThe work was supported by the National Natural Science Foundation of China [51965008].Notes on contributorsJiayong WuJiayong Wu was born in 1996 in Zunyi, Guizhou Province, China, and is currently a master’s student in the School of Mechanical Engineering at Guizhou University. His research interests include performance optimization and environmental adaptation studies of fuel cell bus systems.Jin ZhaoJin Zhao received the B.S. degree from the Chongqing University, Chongqing, China, 1994, the M.S. degree from the Guizhou University, Guiyang, China, in 2004, and the Ph.D. degree from the Ecole Centrale de Lille, Villeneuve D’Ascq, France, in 2010, respectively. His current research interests include intelligent and electric vehicles, vehicle dynamics and control.Zhao LiuZhao Liu graduated from the School of Mechanical Engineering, Guizhou University, China, and is currently a PhD student at Xi’an Jiaotong University, China. His research interests include energy management and control strategy design for fuel cell buses.He YangHe Yang is a master’s student at the Key Laboratory of Advanced Manufacturing Technology, Ministry of Education of Guizhou Province, Guizhou University, China. His research interests include thermal management and control strategy improvement of fuel cells.