Cascaded voltage collapse

The dynamic phenomena of power system voltage collapse are analyzed by the method of dynamic simulation using induction motor models. From the viewpoint of dynamic phenomena, the voltage collapse starts locally at the weakest node and spreads out to the other weak nodes. The main conclusions drawn from this study are as follows. The voltage can be recovered, even after the node voltage is lowered beyond its static critical value. The operating state corresponding to the lower voltage solution is not always unstable. It could be stable depending upon the dynamic characteristics of individual loads, even if they are not of constant impedance type. The voltage collapse is initiated at the weakest node and spreads out to the other weak nodes. These results can be applied to radial voltage collapse phenomena