A technique for real time detection of voltage collapse in power systems

A technique for real time detection of voltage collapse in power systems is presented in this paper, which requires a very modest amount of computations to be performed. This method requires only the voltage phasor information at a bus and the network admittance matrix to evaluate the system voltage stability at a bus in the form of voltage collapse prediction indexes. These indexes can be used by the central load despatch centres to assess the power system voltage stability in real time and are a very helpful tool to initiate corrective actions based on the index value. The technique was tested for different IEEE test systems and some of the simulation results for the IEEE-118 bus system are presented. The technique performed satisfactorily when different contingencies are performed on the IEEE test systems. Real time implementation of this technique using phasor measurement units is also discussed.