MULTIOBJECTIVE DECISION-MAKING IN STOCHASTIC ECONOMIC-DISPATCH

Recently, multiple objective decision making has been well established as a practical approach to seek satisfactory solutions to decision making problems in limited resources, information and cognitive ability of the Decision Maker (DM). In the past, it was normal to assume well behaved and deterministic system data. Now the trend is to assume them variable and uncertain for more realistic approach. This paper deals with decision making methodology based on fuzzy set theory in order to determine the optimal generation dispatch with due consideration of uncertainties in system production cost and randomness of load demand. The classical economic dispatch problem is formulated as stochastic multiobjective optimisation problem where operating cost and variance of generation mismatch are two non-commensurable objectives. Such problems are solved to generate non-inferior solutions. Weighted sum technigue is used to simulate trade-off relation among the conflicting objectives in the non-inferior domain. Once the trade-off has been obtained, fuzzy set theory helps the power system operator (DM) to choose the optimal operating point over the trade-off curve and adjust the generation levels in the most economic manner. Validity and effectiveness of the proposed method has been demonstrated by analysing a sample power system comprising three generators.