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 decisionmaking regarding the optimal sizes of the components of windpowered 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.