Optimal Economic Load Dispatch with Prohibited Operating Zones Using Large to Small Area Technique

Abstract

In practical power plant operation, the economic load dispatch problem is not straightforward. The objective function is generally differentiable (in a quadratic form). It can change to non-differentiable (non-smoothing) or discontinuous fuel cost curve (prohibited operating zones) in the actual power plant operation. The economic load dispatch problem (non-differentiable) solved by calculus methods based on differential (LaGrange method) will not be relevant again. The method currently being developed is based on artificially (for example, Genetic Algorithm), which does not depend on the form of the objective function. It is very relevant to be implemented. There are prohibited operating zones that will make the economic load dispatch problem more complicated to solve. This complicated problem will be solved more easily by area to smaller area technique, which is the simplest artificial method. In addition, this method can give good accuracy because all subareas are traceable and can work for a large scale based on a big candidate size. The simulation results for 15-unit generators with prohibited zones show that the proposed method is working well. The method has shown a small reduction in total cost compared to particle swarm optimization method, and the total cost has closed to the Lambda Iteration and Dynamic Programming methods.