质子交换膜电解槽控制策略研究

Research on Control Strategy of Proton Exchange Membrane Electrolyzer

目前氢能已成为支撑新型电力系统发展的洁净能源载体,光伏电解水制氢技术是制氢的最佳方式之一。针对光伏电解水制氢系统中的关键设备质子交换膜电解槽(PEMEL),结合其非线性、时变性、强耦合、多输入多输出的设备特性和运行特性,以PEMEL动态模型为研究对象,对其控制策略进行研究,包括比例积分微分(PID)控制、鲁棒控制、模型预测控制(MPC)、容错控制(FTC)策略,分析这四种控制策略的结构和优缺点,并从平稳性、精度、计算复杂度和响应速度四个维度对每类控制策略进行单独评价,为PEMEL控制技术研究及氢能领域的发展提供新的借鉴思路。

The technology of photovoltaic electrolysis of water for hydrogen production not only helps to break through the bottleneck of renewable energy consumption,but also can effectively solve the problems of high hydrogen production cost and green production.Proton exchange membrane electrolyzer(PEMEL)is the key hydrogen production equipment in The system of photovoltaic electrolysis of water for hydrogen production.On the one hand,the instability of the output power of photovoltaic cells will lead to damage to PEMEL equipment and decrease of hydrogen production efficiency;On the other hand,changes in temperature,chemical and physical properties during the operation of PEMEL will also lead to high failure rate,short operating life and low hydrogen production of PEMEL equipment.The above problems limit the commercialization process of PEMEL and the development of green hydrogen energy to a certain extent.However,in the current research,the PEMEL-related control strategies mostly focus on the coordinated control at the system level or the array level,which is not enough to solve the above problems.Therefore,this paper further studies the PEMEL device-level control strategy based on the existing research.Firstly, the process of PEMEL electrolytic hydrogen production has nonlinear and multi-physics coupling characteristics, and a series of complex physical and electrochemical reactions during the process will change the operating state of PEMEL. And the instantaneous dynamic process of PEMEL has a great influence on its hydrogen production efficiency and life. Based on this, a PEMEL dynamic model based on ordinary differential equations is constructed. In addition, for the applicability evaluation of the control strategy, four evaluation indicators of stationarity, precision, computational complexity and response speed are set, and each indicator is divided into three evaluation levels. Secondly, on the basis of the PEMEL dynamic model, the research on the device-level control strategy of PEMEL is carried out.Based on proportional integral derivative (PID) control, robust control, model predictive control (MPC), and fault tolerant control (FTC), various composite control strategies are studied. Among them, around PID control, traditional PID control, fuzzy PID control, adaptive PID control, robust PID control and predictive PID control are studied;around robust control, H-infinity control, sliding mode control (SMC), adaptive inversion sliding mode control (AISMC), and robust control method based on sum of suqares decomposition technology (SOSRCA) are studied;around MPC, traditional MPC, nonlinear model predictive control (NMPC), generalized predictive control (GPC), Data-driven MPC and fuzzy MPC are studied;around FTC, active fault tolerant control (AFTC) and passive fault tolerant control (PFTC) are studied. The research contents of the above composite control strategies include control principle, structure and control characteristics, and each type of control strategy is evaluated from the four dimensions of stability, precision, computational complexity and response speed. Finally, through the comparative analysis of each compound control strategy, the advantages and disadvantages of various commonly used control strategies are summarized. Combined with the operating characteristics of PEMEL, an adaptive PID control strategy is proposed as the optimal solution for PEMEL control. However, there are still many key technical issues in the device-level control strategy of PEMEL that need to be further studied. details as follows: Solve the problem of reducing the cost of key equipment in the control system;Solve the problem of reducing the computational complexity of complex control systems;Since PEMEL is a multi-variable-multi-objective system, and the current control strategy considers few control objectives, the coordinated control between the control objectives is also a key problem to be solved urgently;Most of the current advanced control methods are complex and difficult to apply in practical engineering.