PURPOSE: To make it possible to utilize a large torque during rotation at a low speed, by constituting a variable reluctance motor using the stator parts, which are opposed to the surface other than the permanent magnet parts of a yoke on the rotor side.

CONSTITUTION: The inner periphery of a yoke (RF)2 on the toothed rotor side is constituted in the same way as a conventional brushless motor (BM). On the outer periphery of the yoke RF2, yoke teeth 5 are provided. Around respective case teeth 6 of the inner periphery of a toothed case 8, which are opposed to the yoke teeth 5, exciting coils 7 for low-speed driving, which are wound in an identical direction are wound every other tooth. The phase of the case teeth 6 shifted by 60 degrees to censitute a three phase variable reluctance motor (RM) in which the poles at axially symmetrical positions become in-phase with each other. In the brushless motor BM when rotating at a low speed, the current application of exciting coils 4 placed on its inner peripheral side is performed according to the magnets, which are opposed to stator sided yokes 3. The current application-driving of the exciting coils 7 for low-speed driving, which are provided in the RM part of the outer periphery of the brushless motor BM, are performed using a dedicated control circuit too. Therefore, the torque of the brushless motor BM when rotating at a low speed can be made large.