Optimal operation of active distribution systems based on microgrid structure

This paper presents a novel probabilistic-based procedure for improving the operation quality of the active distribution systems (ADSs) which have high penetration level of the renewable distributed generations (RDGs). In the proposed policy, the energy storage devices (ESDs) as important parts of the microgrid (MG) are sized and sited in ADS and the operation of ADS is performed simultaneously by integrated management and coordination of all distributed energy resources (i.e. RDGs and ESDs). To model the state of the charge (SOC) of ESDs at each hour, it is combined with the probability density functions (PDFs) of RDGs and loads by Monte Carlo simulation (MCS) algorithm. This issue has not been stated in the previous researches. Also, in an innovative approach, the operation quality is examined more accurately by testing the possibility of MG construction in the modified ADS based on technical criteria such as adequacy, efficiency, voltage profile indices. A powerful multi-objective optimization method named non-dominated genetic algorithm-II (NSGA-II) is employed for solving the problem. The results of the proposed model are compared with those of conventional operation methods by implementation on a 33-bus test ADS.