Optimal operation planning of distribution systems under uncertainty in load modeling by using decentralized energy resources

Abstract

Abstract The new elements connected in electrical distribution systems increase the complexity of grids as well as planning and operating. The benefits of classical techniques, such as Conservation Voltage Reduction (CVR), combined with a coordinated operation of distribution elements, can contribute to increase efficiency and to reduce energy consumption of the distribution systems. This paper proposes an optimization model for a day-ahead operation of an unbalanced distribution system with photovoltaic distributed generation (DG) penetration. The CVR technique will be considered in deterministic, stochastic and robust approaches, considering the uncertainty of its parameters in the load modeling. The proposed optimization model aims to minimize energy consumption at the substation considering the operation of traditional elements, such as On Load Tap Changers (OLTC) at substation and capacitor banks (CB), but also modern elements, such as intelligent photovoltaic inverters. In the proposed approach, the mathematical problem, initially modelled as a mixed-integer non-linear programming problem, was converted into a continuous linear programming problem. The results were obtained using a modified IEEE123-bus test system indicating good results for utilities to save energy and reduce power demand in three optimization approaches: deterministic, stochastic and robust, and the last one proved to be better for being conservative for voltage violations and lower computational burden.