Abstract
The paper has investigated switching and fault surges in a power system connected with dispered power sources. Based on EMTP simulation results, the effects of various parameters, such as the capacity of a main source and distributed sources, on switching overvoltage characteristics are investigated. It is found that considering the switching surge overvoltage is sufficient from the viewpoint of protection and insulation design of equipment. In a system with a large wind farm, a switching overvoltage becomes smaller. Also, EMTP simulations are carried out to investigate excessive switching overvoltages due to multiple circuit breakers and load switches operation in a distributed power station with station loads connected to a main network, and it is found that an overvoltage more than 10 times of the rated voltage appears due to inductive current interruption under a specific switching condition.
