Computational voltage stability assessment of large-scale power systems

The problem of voltage instability occurring in power systems and various voltage instability indicators proposed in the literature are reviewed in this paper. A voltage stability margin in terms of the active power that the system can supply before voltage instability occurs is proposed. Two voltage stability assessment programs, one developed by EPRI, the Voltage Stability Analysis Program (VSTAB), and the Voltage Eigen Value Analysis Program (VEVA) developed at Tulane University, are compared. The output of these programs as applied to the IEEE 30-bus test system is tabulated.