A three-phase/two-phase rotary transformer including a three-phase portion and a two-phase portion that are movable in rotation relative to each other about an axis A. The three-phase portion includes a first body made of ferromagnetic material and three-phase coils, the two-phase portion including a second body made of ferromagnetic material and two-phase coils. The second body defines a first annular slot of axis A and a second annular slot of axis A, the two-phase coils including a first toroidal coil of axis A in the first slot, a second toroidal coil of axis A in the first slot, a third toroidal coil of axis A in the second slot, and a fourth toroidal coil of axis A in the second slot, the first coil and the fourth coil being connected in series, the second coil and the third coil being connected in series.