Defining the parameters of a power transmission line equivalent circuit on the basis of phasor measurements

Abstract

Although considered to be constant, these parameters depend upon the element actual load, weather conditions and other factors. Consequently, the results of the outlined problems may be subject to significant bias due to the difference between the reference and the actual elements parameters. Hence the task of identifying the actual equivalent circuit parameters is of paramount importance. In terms of power system control the actual measurements are to be used in order to provide the relevant information on the considered power system component state. As for the transmission lines, the state measurements must include the currents and voltages at both ends of the line regarding the Π-shaped equivalent circuit. That said, at present time the equivalent circuit parameters might be defined involving modern systems of phasor measurements (WAMS) on a real-time basis. The method of defining the equivalent circuit parameters based on phasor measurements along with general relations between power system state parameters is proposed. It should be noted as well that while dealing with the actual WAMS data obtained from power system the measurement errors influence the results quite substantially.