Radiation noise is generated when a semiconductor element part installed in a power unit performs a switching operation. In order to reduce such radiation noise, a core is provided outside the power unit. The closer the core is arranged to the semiconductor element part which is the source generating the radiation noise, the greater the effect of reducing the radiation noise. However, because there is no space to provide the core inside the power unit, there is a limit to the extent to which the radiation noise can be reduced. Thus, the present invention provides a power unit comprising a core in the interior thereof. In this power unit, a first output-side conductor bar (16), a second output-side conductor bar (17), and a third output-side conductor bar (18), which are connected to an output of an inverter (3), are provided with a first converged part (15) in order to arrange a first core (6) inside the power unit (2). The first converged part (15) penetrates a first penetrating part (33) in the first core (6) provided inside the power unit (2).