This chapter presents a novel Harmony Search (HS) algorithm used to solve security constrained optimal power flow (OPF) with various generator fuel cost characteristics. HS is a recently developed derivative-free, meta-heuristic optimization algorithm, which draws inspiration from the musical process of searching for a perfect state of harmony. This chapter analyses the evolution of the populationvariance over successive generations in HS and thereby draws some important attention regarding the explorative power of HS. This novel methodology of modified population variance harmony search algorithm (PVHS) easily takes care of solving optimal power flow problem even with non-smooth and piecewise cost functions. This PVHS algorithm was tested on the IEEE30 bus system with three different types of cost characteristics and compared with other reported results.
B. K. Panigrahi, Dr. V. Ravikumar Pandi, Das, S., and Abraham, A., “Population Variance Harmony Search Algorithm to Solve Optimal Power Flow with Non-Smooth Cost Function”, in Recent Advances In Harmony Search Algorithm, Z. Woo Geem, Ed. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010, pp. 65–75.