Optimal Capacity Allocation Method of Grid-Connected Wind and Solar Hydrogen Storage System Considering Stepped Carbon Emissions and Time-of-Use Electricity Price

Due to the high proportion of renewable energy access, the reasonable capacity allocation of each unit of the system is the premise to ensure the economic, environmental protection and reliable operation of the system. A grid-connected hybrid energy storage system with hydrogen energy storage and battery is proposed, which takes the total annual net present cost, load deficiency rate and relative standard deviation of tie line power as the objective function. Considering that the system will generate carbon emissions from power purchase from the power grid, a stepped carbon emission model is established, which is included in the total annual net cost of the system to establish an optimal allocation model of system capacity, and an improved operation strategy considering time-of-use electricity price is proposed. Then, the multi-objective optimization algorithm is used to solve the optimization problem, and the optimal capacity allocation scheme of fan, photovoltaic and energy storage is obtained by making the optimal solution set decision based on the improved Critic-Topsis model. In the analysis of numerical examples, the optimal configuration schemes of three different Mode of operation systems are compared and discussed, and the superiority of the improved operation strategy is proved.