Investigation of a voltage collapse incident in Sri Lankan power system network

In the five years to 1998, seven major blackouts have been observed in the Sri Lankan power system network. However no proper investigation has been carried out to understand the phenomena responsible for these events. An effort has been made, in the present work, to carry out detailed investigation of one of the incidents that took place on 2nd May 1995. The possibility of voltage instability and collapse has been explored. Both static and dynamic voltage stability assessment of the system have been carried out for the pre-disturbance condition and also for the line outage cases leading to the collapse. Investigations reveal that the incident on 2nd May, 1995 in the Sri Lankan network was a case of dynamic voltage instability