Co-Optimization Strategy of Island Distribution Grid and Time-of-Use Pricing Considering the Time Response Characteristics of Multiple Interruptible Loads

Abstract

Currently, island grids are being rapidly constructed in various regions, and the stochastic nature of renewable energy generation output provides a great challenge for the economic dispatch of island grids. In terms of demand-side management, the models used in existing studies in considering time-of-use pricing as well as interruptible loads are still relatively simple, which makes it difficult to fully utilize their potentials in scenarios where the number and types of controllable loads in the distribution network are increasing. For this reason, this paper firstly analyzes the time response characteristics of users participating in interruptible load protocols. Moreover, this paper proposes corresponding time-domain compensation means, and establishes a multi-type active load model based on time-of-use pricing. Secondly, the time-of-use pricing setting and the optimal scheduling of the active distribution network are integrated into a unified optimization problem in order to strengthen the guiding effect of the time-of-use pricing mechanism on the users and to achieve the overall economic optimization. Finally, a mixed integer nonlinear programming model for day-ahead and intraday integrated scheduling is developed to consider the source-storage-load characteristics within the distribution grid. Compared with the constant tariff model and the traditional TOU model, the co-optimization method of time-of-use pricing formulation and active distribution grid dispatch are improved in terms of economic efficiency of the island grid.

Keywords

• Island distribution networks
• renewable energy generation
• time-of-use pricing
• ILs
• grid scheduling