Simulation and optimization of blackstart restoration plan in Bhutan using DIgSILENT

Blackouts in Power system are rare in occurrence. However, it is very important to have plans and systems in place to handle any eventuality even if it is remote. After any power blackout, it is necessary to bring power back to normalcy as quickly and reliably as possible. An effective system restoration plan reduces the impact of an outage on customers and on the economy of the affected area while reducing the probability of damage to equipment. This paper deals with the initial restoration process and the concept of bottom up approach of restoration is presented. Simulations are carried out on a test network with hydropower plant developed in DIgSILENT PowerFactory. The simulations mainly focus on parameters such as load pick up, system frequency and voltage and its effects on the load size, time and distance. Using these analyses, a set of guidelines is formulated for a safe and efficient blackstart procedure of a system.