Microbial electrolysis cell optimization using a super-twisting-based extremum seeking control embedded in FPGA

• Published in: International journal of dynamics and control Vol. 13; no. 9
• Main Authors: Torres-Zúñiga, Ixbalank, Colín-Robles, José de Jesús, López-Caamal, Fernando, Cea-Barcia, Glenda, Alcaraz-González, Víctor
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer Nature B.V 01.09.2025
• Subjects: Closed loops; Controllers; Cyclones; Dilution; Electrolysis; Field programmable gate arrays; Floating point arithmetic; Hydrogen production; Microorganisms; Optimization; Personal computers; Twisting
• ISSN: 2195-268X; 2195-2698
• DOI: 10.1007/s40435-025-01810-7

In this work, we address the problem of online maximizing the hydrogen production rate of a continuous microbial electrolysis cell (MEC) by using the dilution rate as the optimizing control input. A discrete-time Super-Twisting-based extremum seeking control strategy is proposed to solve such an optimization problem online. To minimize hardware resources and power consumption, the floating point-based digital architecture related to the extremum seeking controller is designed and embedded in an FPGA device. Closed-loop simulations demonstrate the feasibility of the extremum seeking control strategy. The model of the MEC is implemented in a personal computer (PC), while the extremum seeking controller is embedded in a Cyclone II FPGA. The RS-232 interface is used to communicate between the FPGA and the PC. Results show that the digital architecture of the extremum seeking control uses 10.75% of the total logic element, 2.34% of the dedicated logic registers, and 20% of the 8-bit multipliers of a Cyclone II FPGA and consumes only 126 mW.