A Cascaded Improved Harmony Search for Line Impedance Estimation in a Radial Power System

Abstract This paper develops cascaded improved harmony search (CIHS) based on meta-heuristics called harmony search (HS) and its variant, called improved harmony search (IHS). CIHS literally cascades several IHSs serially. Even though seemingly CIHS is simple to implement, it is effective in escaping poor local optima which HS and its variants have suffered from. The proposed CIHS is less sensitive to parameter setting and less time-consuming at each iteration than a conventional IHS with the same harmony memory size, since a much smaller-scale IHS is carried out in CIHS. Using the proposed CIHS, we formulate a line impedance estimation problem to which CIHS can be practically applied. We derive detailed line impedance estimation procedures for a general radial system. Finally, the performance of CIHS is validated through line impedance estimation.