Emergency Reactive Power Control Method Incorporating Post-fault Electrical Quantity Response Characteristics

The dynamic characteristics of induction motor loads have an important impact on the transient voltage stability of power system. A fault causing stalling of induction motor loads may lead to voltage instability or even collapse in power system. In this paper, based on the electromagnetic torque and mechanical torque characteristics of induction motor load, the voltage instability mechanism is analysed, and the voltage value and slip value of induction motor loads under critical voltage stability are derived. Furthermore, taking into induction motor end voltage monitoring values and different operating conditions, the amount of reactive power control measures are quantitatively evaluated. An emergency reactive power control method based on a two-stage action judgement including event and response is proposed to improve the system voltage stability. The method's effectiveness is finally validated in single-machine two-node system (SMTNS).