A steady state voltage monitoring and control algorithm using localized least square minimization of load voltage deviations

This paper describes recent work on the theoretical and algorithmic enhancements of the MIT method for power system steady-state voltage monitoring and control. Under the conditions that no dynamic voltage problems are present, the method is intended primarily: to monitor steady-state voltage and reactive power conditions; to identify potential problem situations; and to make decisions regarding their severity. The developed method utilizes various reactive power resources on the power system to remedy voltage violations. The corrective actions suggested are either in the order assigned by the operator or according to efficiency criteria, determined by this algorithm. The corrective actions ensure minimum possible voltage deviations from a given desired voltage profile. Corrective actions are considered to be optimal in this sense. The method has the unique feature of identifying minimum number of most effective corrective actions so that voltages are maintained within the given limits. The method does not solve the exact load flow equations, and therefore it avoids inversion of a full system size matrix. Reactive power scheduling is computed so that the resulting load voltages, are within pre-specified target values. The computational time does not increase significantly with increase of power system size, since no inversion of a system size matrix is needed. Numerical tests on a small and large scale electric power system (IEEE 39 and New England 1726) are presented and analyzed.