| Abstract |
The evaporation cooling system has been applied increasingly in recent years to selfcommutated converters for various urban railway systems. With evaporation cooling one makes use of the physical phenomenon that a boiling liquid at constant pressure will not change its tempareture when heat is either added or removed. The fluorine-chlorine derivative of ethane, R 113, has turned out to be the optimum coolant for evaporation cooling applications. This cooling system requires no pump because boiling vapour is used as the medium to carry the heat of the electrical components to the condensator with a large surface area. The immersion and nonimmersion cooling are discussed. Mainly, the can cooling for semiconductors is considered. BBC Brown Boveri designs and builds converters with evaporation cooling for various urban railway systems. |
