燃料电池空气系统非奇异滑模控制

Non-Singular Sliding Mode Control for Air System of Fuel Cell

为了提高燃料电池的效率和使用寿命,必须对其多个状态进行精确的控制。首先,建立了面向控制的燃料电池空气系统四阶非线性方程,并进行模型有效性验证。然后,针对空气供给系统压力和空气流量的非线性和强耦合性等特点,提出了一种基于全局反馈线性化理论的非奇异终端滑模控制策略。反馈线性化通过对空压机转速和背压阀开度的协同控制,将非线性模型转化为线性模型,实现对阴极压力和空气流量的解耦;考虑空气系统在复杂环境下受到不确定性扰动,设计比例积分观测器对扰动进行观测以减少环境影响;在此基础上,设计非奇异滑模控制器。仿真结果表明:非奇异滑模控制的阴极压力和过氧比各误差积分均小于传统滑模和反馈线性化控制,可显著提高燃料电池空气供给控制系统精度和鲁棒性,对今后研发高精度燃料电池阴极空气供给控制系统提供参考。

In order to improve the efficiency and service life of fuel cell,its multiple states must be precisely controlled.The fourth order nonlinear equation of control-oriented fuel cell air system was established and the validity of model is verified.Then a non-singular terminal sliding mode control strategy based on global feedback linearization theory was proposed for the nonlinear and strong coupling characteristics of air supply system pressure and air flow.The feedback linearization transforms the nonlinear model into a linear model through the coordinated control of air compressor speed and back pressure valve opening,realizing the decoupling of cathode pressure and air flow.Considering the uncertain disturbance of air system in the complex environment,a proportional integral observer was designed to observe the disturbance to reduce the environmental impact.A non-singular sliding mode controller was further designed.The simulation results show that the error integrals of the cathode pressure and peroxide ratio of non-singular sliding mode control are less than those of the common sliding mode control and feedback linearization control,which significantly improves the accuracy and robustness of the fuel cell air supply control system and provides a reference for the future development of the high-precision fuel cell cathode air supply control system.