Integrated planning of micro-grid for efficient utilization of photovoltaic generation considering complicated operation scenarios

In view of the inadequate consideration of scenario diversity in traditional micro-grid (MG) planning, an integrated MG planning method for efficient photovoltaic (PV) utilization incorporating complicated scenarios was proposed in this paper. Through quantifying the impact of network contingencies on PV output and its corresponding economic expenses, the security risk coefficient was introduced, and based on which a composite evaluation function for indicating photovoltaic (PV) contribution under normal and contingency scenarios was developed. For the logical discrepancy between different optimization objectives, a bi-level integrated planning model of MG was proposed. It co-optimized the allocation of PV and energy storage together with network reconfiguration to minimize the total economic cost as upper objective and maximize the expected PV generation in the lower level. The model was solved by using a hybrid algorithm, which combined harmony search and probabilistic optimal power flow based on point estimation. The results of the case study demonstrate that by applying the proposed methodology, PV under MG can be used flexibly and efficiently, the overall benefits in actual situations can be improved, and the coordinated schemes that properly satisfy different planning motivations can be achied.