Application of the sensitivity concept to the optimal reactive power distribution in power systems

In this study the mathematical analysis of the reactive power distribution in a power network under optimal operating conditions is presented. Voltage control at certain nodes of the power network is considered. The sensitivity concept is applied in order to re-optimize the power flow in the network. The sensitivity matrices for the voltage and phase shift dependence are deduced and the relevant results are discussed. The proposed technique reduces the computer computation time considerably. The saving in computer time derives from the study of the deviation problem of the last computer optimal power flow in the power network as a whole. Deviations are found at only a few busbars of the power system. The proposed analysis is applied to three large multi-node power systems.