串联型滑模结构的燃料电池供气系统控制研究

Research on the control of fuel cell gas supply system with tandem sliding mode structure

针对燃料电池空气供给系统动态性能易受负载变化和外界环境因素影响的问题,设计了一种由超螺旋滑模控制与终端滑模控制相结合的串联型控制策略。建立了面向控制的五阶动态模型,提出了在负载变化时供气系统跟踪最佳过氧比、最大净输出功率和阴极压力测量的控制问题;提取最佳期望值并设计控制器,利用Lyapunov方法进行闭环稳定性验证。仿真分析可知,所搭建的观测器扰动估计值与理论实际值误差在0.01%以内,且本文方法与PID控制相比过氧比跟踪最佳期望值响应时间提高了6.9%,最大净功率输出值提高0.2%,阴极压力响应时间相比提高了60%。由结果可得,本文策略在负载变化时可以有效的控制供气系统过氧比跟踪最佳期望值并输出最大净功率,能够准确、迅速的估计阴极压力,能够较好的估计扰动,具有较强的抗干扰能力。

Aiming at the problem that the dynamic performance of the fuel cell air supply system is susceptible to load changes and external environmental factors,a tandem-type control strategy combining super-helical sliding mode control and terminal sliding mode control is designed.A control-oriented fifth-order dynamic model is established,and the control problem of tracking the optimal oxygen excess ratio,maximum net output power and cathode pressure measurement of the air supply system during load change is proposed;the optimal expectation value is extracted and the controller is designed,and the closed-loop stability is verified using the Lyapunov method.Simulation analysis shows that the constructed observer perturbation estimate is within 0.01%error from the theoretical actual value.Compared with PID control,the response time of tracking the optimal expected value of the oxygen excess ratio is improved by 6.9%,the maximum net power output is increased by 0.2%,and the response time of cathode pressure is improved by 60%.From the results,it can be concluded that the strategy of this paper can effectively control the oxygen excess ratio of the gas supply system to track the optimal desired value and output the maximum net power when the load changes,can accurately and rapidly estimate the cathode pressure,can better estimate the perturbation,and has a strong anti-disturbance ability.