Devices Selection for Medium Voltage DC Solid State Circuit Breakers

Abstract

DC grid has been treated as a viable solution to solve green-house effect and reduce the cost of fossil fuels. Compared with AC grid, DC grid shows many inherent advantages. However, over current protection for DC grid require fast response. To solve this problem, solid state DC circuit breakers need to be promoted. In this paper, thermal property was taken into consideration to find the most suitable semiconductor devices. Per unitized thermal resistance of the heat sink to the ambient was used to find the reasonable conducting current.