Optimal dispatching of power grid integrating wind-hydrogen systems

In power grid integrating wind-hydrogena systems, the power balance constraints may result in large-scale wind curtailment during the valley-load period. Additionally, the classic two-stage dispatching strategy cannot evaluate the real-time hydrogen-production efficiency loss in the day-ahead stage, while the one-stage dispatching method will result in computation difficulty or a non-optimal result with or without the full-scale prediction horizon. To address this problem, a novel dispatching strategy is presented in this paper. Considering the electricity and heat demand for hydrogen production, a molten salt heat storage system (HSS) is used to improve the operational flexibility. The external characteristics of hydrogen production are modelled. On this basis, an efficiency-decision method that determines the optimal hydrogen production power is presented; thus, the decision-making variable number can be notably reduced. Considering the real-time power fluctuation, a novel energy dispatching model is proposed in the day-ahead stage to optimize efficiency decisions and thermal power units. Using linearization techniques, this model converted a classic mixed-integer quadratic programming (MIQP) problem and solved it efficiently. Simulation studies on an IEEE-30-node power grid integrating wind-hydrogen systems indicate that the proposed dispatching strategy can reduce the operational cost of the power grid by 4.4%. The results confirm the effectiveness of the proposed dispatching strategy.

Automated summary

This paper proposes a new dispatching strategy for power grid integrating wind-hydrogen systems, which can reduce operational costs by 4.4% and improve efficiency.