Variable Load Matching Design and Simulation of Hydrogen Flow Control System for Fuel Cell

Abstract:

Addressing the challenge of hydrogen flow control in the on-board proton exchange membrane fuel cell system under variable loads， a control system architecture and method for hydrogen flow load matching based on proportional pressure reducing valve and flow control valve were proposed. The comprehensive model from the hydrogen tank to the fuel cell stack was established. Control strategies for the proportional pressure reducing valve， flow control valve， and hydrogen circulation pump were designed and validated through simulations. The results show that the anode pressure of the stack can promptly track the set pressure with a response time of approximately 2~3 s. The hydrogen flow can adjust to load variations， with the transient overshoot correlating positively with the pressure response speed. In a stable state， the hydrogen utilization rate remains above 95%， the hydrogen excess ratio exceeds 1.27， and the nitrogen content in the supplied gas is below 5%， meeting the stack performance criteria.