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In this paper, it is shown that the application of a dynamic brake or thyristorcontrolled braking resistor (TCBR) at the generator terminals enhances the power transfer limit over a transmission line greatly. Two types of dynamic brake configuration have been considered here: a 3-phase, bidirectional, fullwave, Y-connected, phase controlled conventional brake and a 3-phase, fullwave, thyristor-controlled rectifier bridge. A simple rule-based '' ON-OFF'' control law based on the local measurement of generator output power and its derivative is proposed in this paper. Detail digital simulation studies using the PSCAD/EMTDC package have been carried out. It was found that with the insertion of the dynamic brake circuit and its associated control, the system is able to recover following 3-line-to-ground faults even at very heavy power transfer levels, which is not possible otherwise.

With the widespread and active consideration of installation of flexible AC transmission systems (FACTS) controllers for better controllability in a power grid, appropriate placement of these devices is becoming increasingly important. Improperly placed FACTS controllers fail to give the optimum performance and, in some cases, can even be counterproductive. As FACTS controllers are expected to maintain stability and security margin in a system for high power transfer level, proper placement strategies of these devices must be examined from different stability considerations; i.e., voltage stability, small signal stability, and transient stability. In this paper, a strategy for placement of shunt compensators has been proposed based on a combined consideration of voltage stability and small signal stability for a moderately large multimachine power system. The results are also validated with the help of electromagnetic transient simulation.