The invention relates to a power module (9) for converting an electric current flowing between an accumulator and an alternating-current motor, said module (9) comprising switching means (10) that can be controlled to authorize the powering of the motor and/or the charging of the accumulator, and an intrinsic control unit (13) connected to said switching means (10) and capable of delivering opening and/or closing signals to said switching means (10), said intrinsic control unit (13) being further capable of exchanging data with a remote control unit, with a potential barrier.