Inversion device, motor controller, motor assembly and vehicle

The invention relates to an inversion device, a motor controller, an electric assembly and a vehicle, the inversion device comprises a capacitor module and a power module, the capacitor module comprises a capacitor shell, and the capacitor shell is provided with a first flow channel; the power module is installed on the capacitor module, the power module comprises a plurality of power pipe fittings and a first conductive part, the first conductive part is electrically connected with the power pipe fittings, the first conductive part is used for being connected with a winding of the motor, and the first flow channel is used for heat exchange of the first conductive part. According to the inversion device, the power pipe fitting and the first conductive piece are installed on the capacitor module, the first flow channel can be used for conducting heat exchange on the first conductive piece, for example, cooling is conducted, the cooling effect is improved, the assembling difficulty can be lowered, and the product integration degree and the automatic assembling capacity can be improved.