A Multi-Period Model for the Optimal Reactive Power Dispatch Problem

Abstract

ABSTRACT : The optimal reactive power dispatch (ORPD) problem plays a key role in daily power system operation. This thesis presents a novel multi-period approach for the ORPD that takes into account three operative goals. These consist on minimizing total voltage devia-tions from set point values of pilot nodes as well as maneuvers on transformers taps and reactive power compensators. The ORPD is formulated in GAMS (General Algebraic Modeling System) software as a mixed integer nonlinear programming problem, com-prising both continuous and discrete control variables and solved using BONMIN (Basic Open-source Nonlinear Mixed INteger programming) solver. The most outstanding bene-fits of the proposed ORPD model is the fact that it allows an optimal reactive power con-trol throughout a multi-period horizon, guaranteeing compliance with the programmed active power dispatch. Also, the minimization of maneuvers on reactors and capacitor banks contributes to preserving the useful life of these devices. Furthermore, the selection of pilot nodes for voltage control reduces computational burden and allows the algorithm to provide fast solutions. Results on the IEEE 57 and IEEE 118 bus test systems evidenced the applicability and effectiveness of the proposed approach.