Voltage collapse phenomena are highly affected by reactive power generation limits. Saturation of the reactive power generation limits of a unit may result in a deterioration of the voltage stability. However, in some cases when the power network is operating close to the voltage collapse point, the reactive power generation saturation of a unit can change the system voltages immediately from stable to unstable; thus, a dynamic voltage collapse leading to blackout may follow. This paper presents a steady-state analysis of the immediate instability caused by reactive power generation saturation phenomena. For this purpose, the paper proposes a novel index that evaluates when and why a reactive power generation saturation will only result in a deterioration of the system voltage stability or, on the contrary, it will make the system voltages immediately unstable.
Keywords: Reactive power generation limits; Voltage stability; Voltage collapse; Transcritical bifurcation
Electric Power Systems Research. Volume: 79 Issue: 9 Pages: 1292-1299
Journal Impact Factor: JCR impact factor 2.856 (2017)
DOI reference: 10.1016/j.epsr.2009.03.006
Published on paper: September 2009.