Power Quality Considerations in the Planning Phase of Stand-Alone Wind-Powered Micro-Grids

This paper proposes a novel multi-objective optimization modelling framework for the optimal design of stand-alone micro-grids (MGs) with high wind power penetration in the presence of nonlinear loads. The key objective of the proposed modelling framework is to facilitate decision-making regarding the optimal sizes of the components of wind powered MGs under both the source-end voltage and load current harmonics, which deteriorate the power quality of the system. The problem is formulated as a bi-objective optimization model to minimize the whole-life cost of the system, whilst minimizing the whole system harmonics distortion level, and is solved using the elitist non-dominated sorting genetic algorithm (NSGA-II). The utopia point on Pareto optimal frontier is also determined using a fuzzy decision-making approach. The applicability and effectiveness of the proposed modelling framework are demonstrated on a representative stand-alone wind-powered MG conceptualized for Stewart Island, New Zealand. The simulation results indicate that the proposed model can effectively address the power quality issues in the planning phase of wind-powered sustainable energy systems serving typical nonlinear residential loads.