Power Flow Control with UPFC in Power Transmission System

Abstract

In this paper the performance of unified power flow controller is investigated in controlling the flow of po wer over the transmission line. Voltage sources model is utilized to study the behaviour of the UPFC in regulating the active, reactive power and voltage profile. This model is incorporated in Newton Raphson algorithm for load flow studies. Simultaneous method is employed in which equations of UPFC and the power balance equations of network are combined in to one set of non-linear algebraic equations. It is solved according to the Newton raphson algorithm. Case studies are carried on standard 5 bus network. Simulation is done in Matlab. The result of network with and without using UPFC are compared in terms of active and reactive power flows in the line and active and reactive power flows at the bus to analyze the performance of UPFC . In this paper voltage source model of UPFC is incorporated in Newton Raphson algorithm in order to investigate the control of power flow. Normally there are two ways of solving the load flow equations with UPFC. The sequential method and the simultaneous method: In sequential method the equations of UPFC are separated from the system power balance equations. Both the set of equations are solved separately and sequentially. In simultaneous method all the equations are combined in to one set of non-linear algebraic equations. A jacobian matrix is then formed which is non symmetric in nature. The simultaneous method is used in this paper.