HYDROTHERMAL POWER-SYSTEM LOSS MINIMIZATION - A PROBABILISTIC PERTURBATION APPROACH

We present a formulation of the power system loss minimization problem that includes power demand uncertainty. We assume that the perturbati ons in the system power demand and its resultant effects on the system voltages as random variables with zero mean and some variance. The eq uality constraints associated with the formulation are characterized b y the power flow equations in polar form utilizing the nodal admittanc e matrix approach. The algorithm is applied to 4 different IEEE hypoth esized test system, using Newton's method and Powell's penalty functio n approach, and computational results are obtained. A comparison of th e probabilistic approach with deterministic based solutions for three systems are offered. The difference in voltage profiles and other vari ables may be minimal for smaller systems. However, these differences a ppear to be substantial as the system increases both in size and capac ity.