Dynamic Multi-Parameter Coordination for Enhanced Efficiency and Grid Responsiveness in High-Temperature Power-to-Gas Systems

(HT-P2G) to address intermittency. Unlike low-temperature P2G, HT-P2G requires coordinated regulation of electrolysis current, stack temperature, and feedstock flow rates, which jointly affect efficiency. This paper proposes a maximum production point tracking

(MPPT) strategy for HT-P2G based on a comprehensive multi-domain dynamic model.

The proposed framework coordinates current, temperature, and flow rates to achieve rapid power tracking and improved steady-state efficiency. The model captures SOC stacks, auxiliary modules, and coupled electrical–thermal–hydraulic dynamics. MPPT combines a steady-state optimizer with a feedback controller to handle fast electrical dynamics and slower thermal–hydraulic responses under operational constraints.

Case studies under load steps, high-power loading, and AGC signals show that MPPT achieves 0.15–0.2 s power tracking, improves steady-state efficiency by 4.7% at 600 kW, extends loading capacity by 10.8%, and increases hydrogen production by 9.3% over a 1-hour

AGC profile. The results demonstrate that the proposed method enhances both short-term flexibility and long-term efficiency of HT-P2G systems.