This research paper gives solution for Economic Load Dispatch (ELD) problem with considering valve point effect. ELD is the oldest and most important problem of optimal power flow. Objective of the ELD problems is to find out the optimal combination of power outputs of generating units so as to cope up the load demand at minimum cost while satisfying all the equality and inequality constraints. Conventionally, the function of cost for each unit in ELD problems has been approximately represented by a quadratic equation and is solved using various conventional and artificial intelligent techniques of optimization. Unfortunately, high non-linearity is present in the input-output characteristics of generating units’ due to presences of prohibited operating zones, valve point loading effects, and multi-fuel effects, etc. Thus, the practical ELD problem is formulated as optimization problem of a non-smooth function with equality and inequality constraints, which cannot be solved by the conventional optimization methods. The performance of Cuckoo Search method and PSO with some modifications is tested on a standard test bed system i.e. IEEE 30-bus 6-generators system.
Valve-point Effect, Cuckoo Search Method (CS), Modified PSO (MPSO)
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