Improvement of precise P/V curve considering effects of voltage-dependent load models and transmission losses for voltage stability analysis

The P/V (power/voltage) curve of a power system has been often used for the analysis of voltage stability. If the P/V curve is evaluated with improved precision, then it can have an important role in the analysis of voltage stability. An approach is presented to improve the precision of the P/V curve of a power system, considering the effect of voltage dependency of electric loads and power transmission losses. For electric loads, the use of the voltage-dependent load model, expressed in quadratic form of the bus voltage, has been adopted. For the losses, the re-allocation of transmission losses to each generation bus has been used in the process of power flow calculation for obtaining the P/V curve. Case studies demonstrate the performance of the approach