Power Module and Power Conversion Apparatus Using Same

Abstract

A power module includes a plurality of semiconductor devices constituting upper/lower arms of an inverter circuit, a plurality of conductive plates arranged to face electrode surfaces of the semiconductor devices and a module case configured to accommodate the semiconductor devices and conductive plates, wherein the module case includes a heat-radiation member made of plate-like metal and facing a surface of the conductive plate and a metallic frame body having an opening that is closed by the heat-radiation member, and wherein a heat-radiation fin unit having a plurality of heat-radiation fins vertically arranged thereon is provided at a center of the heat-radiation member, and a joint portion with the frame body is provided at an peripheral edge of the heat-radiation member, and the heat radiation member has a heat conductivity higher than that of the frame body, and the frame body has a higher rigidity than that of the heat-radiation member.

1 . A power module comprising:
 a module encapsulant body sealing a power semiconductor device and a conductive plate facing an electrode surface of the power semiconductor device;   a heat radiation member facing a surface of the conductive plate; and   a holding member which holds the heat radiation member and is mechanically fixed to a housing of a power conversion apparatus,   wherein the heat radiation member has a thermal conductivity higher than that of the holding member, and the holding member is of a higher rigidity than that of the heat radiation member.   
     
     
         2 . The power module according to  claim 1 , wherein the heat radiation member is crimped to the module encapsulant body. 
     
     
         3 . The power module according to  claim 1 , wherein the surface of the conductive plate, which is on the opposite side from the power semiconductor module, is exposed on a surface of the module encapsulant body, and
 the heat radiation member is crimped to the module encapsulant body through an insulating member.   
     
     
         4 . The power module according to  claim 1 , wherein the holding member is a metallic frame body having an opening portion that is closed by the heat radiation member. 
     
     
         5 . The power module according to  claim 4 , wherein the metallic frame body and the heat radiation member constitute a module case configured to accommodate the module encapsulant body. 
     
     
         6 . The power module according to  claim 4 , wherein an external peripheral edge of the heat radiation member is formed in a stepped shape. 
     
     
         7 . A power conversion apparatus comprising:
 a module encapsulant body sealing a power semiconductor device and a conductive plate facing an electrode surface of the power semiconductor device;   a heat radiation member facing a surface of the conductive plate;   a housing in which the module encapsulant body and the heat radiation member are stored; and   a holding member which holds the heat radiation member and is mechanically fixed to the housing,   wherein the heat radiation member has a thermal conductivity higher than that of the holding member, and the holding member is of a higher rigidity than that of the heat radiation member.   
     
     
         8 . The power conversion apparatus according to  claim 7 , further comprising:
 a coolant channel forming body configured to form a cooling channel in which coolant flows,   wherein a surface of the heat radiation member, which is on an opposite side from the surface of the conductive plate, directly faces to the cooling channel.   
     
     
         9 . The power conversion apparatus according to  claim 8 , wherein the holding member partitions a part of the cooling channel. 
     
     
         10 . The power conversion apparatus according to  claim 8 , wherein the coolant channel forming body is integrally formed with the housing. 
     
     
         11 . The power conversion apparatus according to  claim 7 , wherein the holding member constitutes a part of a coolant channel forming body configured to form a cooling channel on an opposite side of the heat radiation member from the power semiconductor device. 
     
     
         12 . The power conversion apparatus according to  claim 7 , wherein the heat radiation member is crimped to the module encapsulant body. 
     
     
         13 . The power conversion apparatus according to  claim 7 , wherein the surface of the conductive plate, which is on an opposite side from the power semiconductor module, is exposed on a surface of the module encapsulant body, and
 the heat radiation member is crimped to the module encapsulant body through an insulating member.   
     
     
         14 . The power conversion apparatus according to  claim 7 , wherein the heat radiation member comprises a first heat radiation member and a second heat radiation member, and the module encapsulant body is sandwiched between the first heat radiation member and the second heat radiation member. 
     
     
         15 . The power conversion apparatus according to  claim 7 , wherein the heat radiation member has a plurality of heat radiation fins on an opposite side from the module encapsulant body.