Patent ID: 8902623

Claim:
A power inverter comprising: a power module that converts a direct current to an alternating current; and a capacitor module that smooths the direct current; wherein: the power module comprises: a plurality of first power semiconductor devices that constitutes U-phase, V-phase and W-phase upper arms of an inverter circuit; a plurality of second power semiconductor devices that constitutes U-phase, V-phase and W-phase lower arms of the inverter circuit; an insulation substrate on which the plurality of first power semiconductor devices are mounted; a power module case that encloses the plurality of first power semiconductor devices and the plurality of second power semiconductor devices and is formed in a rectangular shape including at least a first side and a second side which is disposed opposite to the first side; a first direct current positive terminal and a first direct current negative terminal that protrude from the first side of the power module case; a second direct current positive terminal and a second direct current negative terminal that protrude from the first side of the power module case; an alternating current power line that protrudes from the second side of the power module case; a positive conductor that transmits electric current flowing between the first and second direct current positive terminals and the plurality of first power semiconductor devices; and a negative conductor that transmits electric current flowing between the first and second direct current negative terminals and the plurality of second power semiconductor devices; the capacitor module includes a capacitor positive terminal connected to the first and second direct current positive terminals and a capacitor negative terminal connected to the first and second direct current negative terminals; each of the positive conductor and the negative conductor includes: an extended portion that passes through an area facing the insulation substrate with the plurality of the first power semiconductor devices therebetween; a U-phase junction that is extended to a vicinity of a space between the U-phase first power semiconductor device and the U-phase second semiconductor device; a V-phase junction that is extended to a vicinity of a space between the V-phase first power semiconductor device and the V-phase second semiconductor device; a W-phase junction that is extended to a vicinity of a space between the W-phase first semiconductor device and the W-phase second semiconductor device; and the extended portion of the positive conductor and the extended portion of the negative conductor are laminated by sandwiching an insulation member in a middle of the area.