Cooling device for cooling medium-voltage apparatus using insulated heat pipes

Abstract

The cooling device is suitable for fitting to existing installations, without redesigning them. It consists in using heat pipes ( 12 ) that are partly embedded in the casing ( 10 ) of the apparatus. This embedded portion ( 12 A) of the heat pipe ( 12 ) penetrating into the casing ( 10 ) has a sleeve ( 14 ) that is both electrically insulating and a good conductor of heat. The device is for application to circuit breakers in a medium-voltage, high-amperage electrical installation.

1 . A cooling device using a phase-change heat-transfer fluid for medium-voltage apparatus, comprising:
 at least one heat pipe ( 12 ,  42 A,  42 B);   the device being characterized in that the at least one heat pipe ( 12 ,  42 A,  42 B) penetrates in part into the apparatus and is electrically insulated in this embedded portion ( 12 A) by means of a sleeve ( 14 ) that is both electrically insulating and a good conductor of heat.   
     
     
         2 . A device according to  claim 1 , characterized in that the electrically insulating sleeve ( 14 ) is made of sintered aluminum nitride. 
     
     
         3 . A device according to  claim 1 , characterized in that the electrically insulating sleeve ( 12 ,  42 A,  42 B) is made of sintered boron nitride. 
     
     
         4 . A device according to  claim 1 , the assembly being placed inside a sheath ( 22 ), the device being characterized in that the outside portion ( 12 B) of the heat pipes ( 12 ,  42 A,  42 B) not penetrating into the apparatus terminating at the condensers ( 24 ) possesses an electrically insulating sleeve ( 18 ). 
     
     
         5 . A device according to  claim 1 , characterized in that each heat pipe ( 12 ) possesses an electrically insulating ring ( 16 ) placed on an outside portion ( 14 A) of the electrically insulating sleeve ( 14 ). 
     
     
         6 . A device according to  claim 1 , characterized in that each heat pipe ( 12 ,  42 A,  42 B) possesses an electrically insulating sleeve ( 18 ) on its outside portion.