Economic operation of a microgrid system with amalgamated load shifting/curtailing policy and smart PHEV charging

The aim of load shifting policy (LSP) is to optimize a distribution system's performance and operation economically. Load curtailing policies (LCP) also shave the peak load by offering incentives to customers based on their willingness to curtail loads and in some cases offers monetary benefit to DISCOM too. LSP employs optimization tools and fill in the valleys to lower the peak demand by shifting the elastic loads to hours whenever the electricity price is low. The objective of this novel work is to optimize the scheduling of distributed generations (DG) in a low voltage microgrid (MG) system by implementing LSP, LCP and amalgamated load curtailment and shifting techniques to minimize the total costs of generation. Additionally, the MG system provides the provision to facilitate the Grid to Vehicle (G2V) and Vehicle to Grid (V2G) operating methods of a plug-in hybrid electric vehicles (PHEV). Consequently, an intelligent charging strategy based on real-time tariffs (RTT) imposed by utilities is recommended for PHEV charging integration, to lower the daily charging cost as a whole. The research investigation employed the Differential Evolution (DE) algorithm as an optimization technique. The integrated load shifting/curtailing strategy demonstrated to be more cost-effective and efficient in lowering the total operating cost (TOC) of the system when compared with cases where similar techniques are applied independently, as illustrated by the numerical data. The generation cost in the baseline scenario without any demand-side intervention was the highest. This cost decreased substantially with the implementation of a load shifting policy and showed moderate reduction under a load curtailment strategy. The most significant cost savings were achieved when both load shifting and curtailment policies were integrated. Furthermore, additional economic benefits were observed through the adoption of controlled and smart charging strategies for plug-in hybrid electric vehicles (PHEVs).