Electrothermic Industrial Load Model with a Dynamic Iterative Mechanism for Equivalent Thermal Parameters and Its Application in Demand Response

As a typical electrothermic industrial load (EIL), the adjustable potential of aluminum smelter load has not been fully utilized. The reason is the lack of a precise model to describe the conversion between electricity and thermal energy, and the ignorance of energy consumption related to yield. To address these issues, this paper proposes a price-based demand response (DR) strategy for EIL using an equivalent thermal parameters (ETP) model that considers electro-thermal coupling characteristics and energy consumption changes in the electrolytic process. First, a dynamic thermal balance equation is employed to mathematically depict the energy conversion from electricity to thermal in reduction cells. Second, the ETP model for EIL is derived from the dynamic thermal balance equation based on Taylor expansion, which accurately characterizes the time‑variant relationship between power regulation and electrolysis temperature changes. Finally, an iterative temperature‑power mechanism is embedded into the DR optimization algorithm under TOU tariff to cope with the significant variation of equivalent thermal resistance during regulation. The simulation results demonstrate that the proposed ETP model combined with the iterative algorithm can shift more peak load and reduce more electricity costs for aluminum smelters, especially during an electrolytic aluminum production cycle.