Controlled series compensation for improving the stability of multi-machine power systems

The application of controlled series compensators (CSCs) to increase the damping of dynamic oscillations in multimachine power systems is described. A CSC controller design is presented based on a linearised model of the power system around a given nominal operating point. The pole placement technique is used for calculating the controller feedback gains. A procedure for determining an optimum location for installing a CSC in a power system to provide the most effective damping is investigated. A technique for coordinating CSCs when it is necessary to use more than one CSC in a power system is also discussed. Computer simulations are used to demonstrate the effectiveness of CSCs in increasing the damping of power system dynamic oscillations. A simple power system with nine buses and three synchronous machines is used to demonstrate the design procedure.