Managing Real Power Loss of Distribution System Connected with Distributed Generator Using Least Square Quadratic Approximation

Abstract

This paper compared two scenarios for managing real power loss of a distribution feeder connected with a Distributed Generator (DG). Under planning scenario, the objective is to obtain the optimal purchasing contract, which is a constant power injected from DG to minimize loss of a feeder. In real time operating scenario, the optimal scheduled power of DG to minimize loss for each hour is calculated. These two scenarios are formulated as optimization problems and solved with the proposed Least Square Quadratic Approximation (LSQA) technique. This technique is formulated based on a quadratic nature of a real power loss versus its real power output injected from DG. In term of the obtained results, it is reliable and has high accuracy. A 93-bus radial distribution system connected with a synchronous based DG sizes 7.5 MW under North-Eastern region 2 of Provincial Electricity of Thailand (PEA) is adopted as a tested system. The obtained results shown that managing loss under both scenarios bring benefits to a tested feeder. Moreover, the proposed LSQA technique is easy to understand, thereby can be used alternatively with others present optimization techniques.