Model-Free Control of Alkaline Electrolysis Temperature with Time Delays

Temperature control is a key factor for the proper and efficient operation of alkaline electrolysis systems. Alkaline electrolysis systems are considered as time-delay systems in the design of PID to control the temperature. In green hydrogen production, the electrolysis is coupled to an intermittent renewable energy source. This means that the current applied to the electrolysis is not fully controlled, leading to overshoot and undershoot of the cell temperature, impacting performance and even lifetime. Model-free control is applied to alkaline electrolysis to reduce the overshoot phenomena observed when the system is controlled by a PID. Also to achieve faster stabilization time of stack temperature. Simulation results show that model-free control ensures a stabilization time that is at least 15 min shorter than that of the controller used in comparison with a low level of overshoot.