Multiperiod optimal planning of steam power system for steel plants under time-of-use power price

This paper presents a generalized formulation for the multiperiod optimal planning of the steam power system in the iron and steel industry with minimization of total operation cost including fuel cost, equipment maintenance cost, the charge for power import and the income from excess of generated power exported to the main grid. The optimization model takes into account the varying nature of surplus byproduct gas flows, unit modeling using thermodynamic principles, generation capacity limits, power and steam balance equations and ramp rate limits. It also considers the connection of the steam power system and the main grid regarding the time-of-use (TOU) power price. In order to obtain the optimal solution, an improved particle swarm optimization algorithm (IPSO) is proposed by incorporating a self-adaptive mutation scheme and efficient constraint handling strategies. Finally, a case study of a typical iron and steel industry is considered for illustrating the model and validates the effectiveness of proposed optimization approach.