S.Ye Saukh, A.V. Borysenko

Èlektron. model. 2021, 44(1):03-29



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 using to solve large-scale integer programming problems. To eliminate such an insurmountable limitation in the application of UC-models, the UC-model of loading generating blocks on the cyclic forecasting horizon (UCC-model) is proposed. The UCC model reproduces block-loading modes on a cyclical weekly forecast horizon and does not require initial conditions, as it establishes a relationship between the states of generating blocks at the end and beginning of the forecast horizon. The weekly distance of the extreme points of the forecast horizon in the UCC model can significantly reduce the interaction of the conditions of cyclic loading of blocks. The UCC model adequately reflects the loading modes of generating units of NPP, TPP, powerful CHTPP, HPP and energy storage systems, including powerful PSP. The UCC model is a multi-node model and takes into account the limitations on the volume of electricity transmission by interconnection power lines. The UCC model takes into account system-wide requirements for the placement of primary and secondary power reserves on loaded units, including energy storage systems. The UCC model is a tool for analyzing the adequacy of shunting power in the tasks of medium- and long-term forecasting of power systems development in terms of increasing electricity production of wind and solar power plants.


power system, model, loading of generating units, cyclic forecasting horizon.


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