A power inverter comprises at least a box-shaped housing; and a power module, a smoothing capacitor, a base plate made of a flat plate, and a rotating electric machine control circuit board arranged in order in the housing. The base plate is arranged with the fringes fixed to the inner wall surfaces of the housing, and the smoothing capacitor and rotating electric machine control circuit board are fixed.
1. A power inverter for an electric motor installed in a vehicle, comprising:
a coolant channel body;
a power module having DC terminals for receiving DC electric power and AC terminals for outputting three-phase AC electric power, and power semiconductors for converting DC electric power to AC electric power;
a capacitor module, said capacitor module further comprising a capacitor case, first and second conductors directly connected to respective DC terminals of the power module, and a plurality of film capacitors;
a housing, said housing containing the coolant channel body, the power module, and the capacitor module; and
a holding plate holding said capacitor module;
wherein
one of the electrodes of each of the film capacitors is connected to the first conductor and the other electrodes of each of the film capacitors is connected to the second conductor respectively,
the power module is adjacent to the coolant channel body,
the holding plate is located to counter with the coolant channel body and sandwich the power module with the coolant channel body, and fixed to the housing; and
the capacitor module is located between the power module and the holding plate.
2. The power inverter according to claim 1 , further comprising:
a control circuit board for controlling generation of the AC electric power; and
a driver circuit for controlling the power semiconductors of the power module based on an output of the control circuit board;
wherein the driver circuit being located between the capacitor module and the power module.
3. The power inverter according to claim 1 , wherein
the capacitor case of the capacitor module is made of resin material;
the power module is fixed with the coolant channel body; and
the capacitor module faces the power module across a space.
4. The power inverter according to claim 3 , further comprising a driver circuit board for controlling the power semiconductors of the power module based on an output of the control circuit board, wherein the driver circuit board is arranged in the space between the power module and the capacitor module.
5. The power inverter according to claim 1 , wherein
the coolant channel body is arranged at the lower half side of the storage space of the housing; and
the power module and the capacitor module are arranged at the upper side rather than the coolant channel body.
6. The power inverter according to claim 1 , wherein
the capacitor module comprises a pair of DC power source terminals for receiving DC electric power; and
a power module side terminal for providing at the end of the second portion and for connecting with the DC terminal of the power module.
7. The power inverter according to claim 6 , wherein
the DC terminal of the power module provides a plurality of pair of plus side terminal and minus side terminal;
a plurality of the power module side terminals of the capacitor module are provided; and
the power module side terminals are connected with the DC terminals respectively.
8. The power inverter according to claim 1 , wherein
the first and second conductors have a first portion and a second portion respectively;
the first portion and the second portion are continuously connected by a connecting part; and
the connecting part has a bent form.
9. The power inverter according to claim 1 , wherein
an opening is formed at the coolant channel body;
a plurality of fins for cooling is provided on a cooling surface of the power module;
the fin is projected through the opening of the coolant channel body into coolant; and
the opening is closed by the cooling surface of the power module.
10. The power inverter according to claim 8 , wherein the first and second conductors have a lamination structure in which an insulation sheet is sandwiched therebetween.