燃料电池氢气流量控制系统变负载匹配设计与仿真

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

摘要:

针对车载质子交换膜燃料电池供氢系统负载工况多变时的氢气流量控制问题，提出一种基于比例减压阀与流量控制阀的氢气流量负载匹配控制系统架构与方法。建立了从高压储氢瓶至燃料电池堆的供氢系统整体模型，基于该模型设计了比例减压阀、流量控制阀与氢气循环泵的控制策略，并就某一型号电堆的变负载工况对系统模型与控制策略进行仿真验证。结果表明：电堆阳极压力可快速跟踪给定压力，响应时间约2~3s；氢气流量可适应负载变化需求，其瞬时超调量与压力响应速度成正相关；稳态时氢气利用率维持在95%以上，供氢过量比维持在1.27以上，供气氮含量维持在5%以下，满足电堆性能需求。

关键词:质子交换膜燃料电池;供氢系统;变负载工况;负载匹配;控制策略

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.

Key words:Proton exchange membrane fuel cell;Hydrogen supply system;Variable load;Load matching;Control strategy