Representation of Power System Load Control Instruments in the Unit Commitment Model with Cyclic Horizon of Forecasting

Abstract

Well-known Unit Commitment (UC) models of loading generating units of power systems have a common feature: they are all determined on the basis of linear time, where there are past, current and future periods. UC models are “tied” to the initial conditions and, therefore, cannot cover long-term forecasting horizon due to the excessive computational complexity of algorithms for solving model problems of large-scale integer programming. To eliminate such an insurmountable limitation in the application of UC models, the UC model of loading generating units on the cyclic forecasting horizon (UCC-model) is used. The UCC-model reproduces units loading modes on a cyclical weekly forecast horizon and does not require initial conditions, as it establishes a relationship between the states of generating units at the end and beginning of the forecast horizon. The UCC-model presents a detailed description of the operation of electricity storage systems, taking into account the placement of primary and secondary reserves. Comprehensive consideration of the maneuverability of traditional generation technologies in combination with energy storage systems and opportunities for participation of RES and consumers in load regulation significantly improve the quality of modeling modes of generating equipment in long-term development models. The use of the UCC-model in the tasks of long-term planning of generation development allows to adequately represent the modes of operation of generating equipment and the distribution of reserves in the power system. The use of the UCC-model in the tasks of short-term dispatch control of power systems allows reproducing the features of the distribution of reserves in the electricity storage systems, demand management and distributed generation.