This paper presents various processes of dynamic voltage collapse which is initiated by various power system disturbances, and the impacts of dynamic voltage controllers. According to the analysis results, the composition of induction motors with short time constants affects the voltage collapse strongly. Also, it is proved that the addition of fast acting reactive compensation devices, such as SVC, at high reactive loss sensitivity($$delta$$Q$$_luss/delta$$P$$_L$$) buses could be one of the best countermeasure to escape the voltage collapse.