Investigation of various generator reactive power reserve (GRPR) definitions for online voltage stability/security assessment

Voltage stability in power system is influenced by reactive support at various locations. It is desirable to monitor the reactive power reserves as system conditions change. There is a need to find a relationship between the reactive power reserves and system security with respect to voltage stability margin and voltage violations. In this paper we have investigated how different approaches of generator reactive power reserves (GRPR) relate to voltage stability and voltage violations. In reference [3] the authors presented the relationship between the reactive power reserves and voltage stability margin (VSM). The linear approach presented in reference [3] is further analyzed to take into account the nonlinear nature of reactive power reserves. In this paper the relationship between the reactive power reserve and voltage violations is also included. A nonlinear regression model up to 3^rd order is included to improve the accuracy of the prediction.