Optimal Scheduling Strategy for Energy Allocation of Distributed Electric Heat Storage

Abstract

Electric heat storage (EHS) located on the grid side can improve the flexibility of combined heat and power (CHP) systems to reduce wind power curtailment (WPC), and its capacity is correlated with investment costs. However, a significant amount of distributed electric heat storage (DEHS) on the load side has already been funded and constructed by users and businesses. To effectively utilize DEHS for diverse user types in different geographic locations, a generalized scheduling method is required to address these issues. To fill the technology gap, an innovative optimal scheduling strategy for energy allocation in DEHS is proposed. Firstly, to consider the heat comfort of DEHS users and their willingness to serve grid scheduling, the equivalent energy allocation strategy (EEAS) and increased energy allocation strategy (IEAS) are developed, respectively. Secondly, a general model is proposed to schedule DEHS for different types of users. The electric heat time-shift characteristics of DEHS are used to reallocate the working time of energy storage. Thirdly, numerical simulations are employed to validate the proposed strategy. The proposed scheduling strategies of EEAS and IEAS contribute to the reduction of WPC. The WPC rates are reduced by 14.04% and 29.49%, respectively, when compared to the conventional scheduling strategy of time-of-use. Moreover, compared with EEAS, IEAS makes a significant contribution by providing 27.05% more scheduling space for the grid, thus greatly improving its flexibility in consuming wind power. The WPC can be reduced through the energy allocation of DEHS, while the flexibility of grid regulation is enhanced by increasing the deviation of energy allocation.

Keywords

• Optimal scheduling
• distributed electric heat storage
• equivalent energy allocation strategy
• increased energy allocation strategy