Visualization of voltage stability region of bulk power system

This paper presents a hyper-plane description approach in a critical cut-set space for visualization of voltage stability region (VSR) of bulk power system. The study on a low dimensional integrated feasible region of voltage stability in critical cut-set space shows that it is the union of hyper-planes vertical to coordinates axes that represent upper and lower limits of the line flows in the critical cut-set, and a hyper-plane which describes critical points in critical cut-set space about voltage stability for a given system configuration with perfect accuracy. Here a critical cut-set separates a geographical region, in which the weak nodes of voltage stability are relatively concentrative and can be identified by an improved voltage stability index L_i, from the residual of the configuration. Examples of visualization of integrated feasible region of the Central-China Power System (1305 buses) are also given to validate the method.