Transfer Capability of Long Transmission Lines as Affected by Shunt Compensation

Power transfer capability of a shunt-compensated transmission line is considered. The analysis is based on the pi-circuit transmission line model, which takes into account line losses and capacitance, and source impedances. Results governing the real power flows and voltage angle between the two end-sources are derived. The effect of the shunt compensation at an intermediate node of a long line on the transfer capability of the line is shown. Furthermore, the method allows the optimal location of the shunt compensator to be determined so as to achieve the highest possible power transfer at reduced transmission angle. A computational procedure is then proposed in extending the results to include the determination of the optimal multiple compensator locations for a general symmetric transmission system. Additional insight into the steady-state transfer limit of the compensated system is gained.