Probabilistic planning of a battery energy storage system in a hybrid microgrid based on the Taguchi arrays

The transformation of electrical networks in the context of the new smart grid paradigm unavoidably involves new challenges for electrical component planning. This paper provides a tool for the probabilistic sizing of a battery energy storage system in a hybrid AC/DC microgrid (i.e., a microgrid including AC and DC subsections with AC and DC loads and renewable power generation). The procedure is based on an analytical formulation to assess the total costs sustained by the microgrid for the inclusion of the battery energy storage system. The total costs depend on the random nature of the load demand, the electrical energy prices, and the renewable power generation, therefore, a probabilistic approach has been used. Furthermore, to account for uncertainties that affect the input data, the Taguchi orthogonal arrays are applied which allow significantly reducing the computational efforts while guaranteeing the desired accuracy of the results. The proposed analytical formulation along with the use of the Taguchi orthogonal arrays allows limiting the computational complexity even in presence of a large number of random inputs and discretization levels. A case study based on an industrial hybrid microgrid is presented to analyse the results obtained in terms of the optimal sizing of the battery energy storage system and to investigate the sensitivity with respect to some inputs.