Temperature Control of an Alkaline Electrolyzer using Fractional Order PID

Abstract

Currently, various methods exist for hydrogen production, with alkaline water electrolysis (AWE) being one of the most widely used, achieving a hydrogen purity of 99.9%. Electrolysis systems operate within a specific temperature range to ensure both safety and efficiency. While higher temperatures improve efficiency, they also reduce the corrosion resistance of system components, whereas lower temperatures negatively affect hydrogen production. Therefore, maintaining the temperature within the recommended range of 60° to 80°C is essential in electrolyzer applications. The classical PID controller does not always provide optimal performance for temperature regulation in such systems due to the system's nonlinearities. In this work, a Fractional Order PID controller is proposed as an alternative to the classical PID for electrolyzer temperature control. The performance of both controllers is assessed and compared through simulation scenarios, considering key metrics such as settling time, integral squared error, and overshoot. Additionally, the response of the controllers to system disturbances are analyzed to evaluate their effectiveness in ensuring system stability and efficiency. The results demonstrate that the FO PID controller offers superior performance, making it a promising approach for temperature regulation in real hydrogen generation systems.