インナーおよびアウターロータ型モータの共振条件の検討

抄録

Permanent magnet motor is widely used for many industrial applications because of its high power density and high efficiency. Also, in recent years, the product's rotational speed has become faster and the size has become lighter and more compact. On the other hand, these changes have increased magnetic flux density inside the motor and radial electromagnetic excitation, which causes large noises and vibration. It is known that one of the causes of the noise is the resonance between the electromagnetic excitation force and a periodic symmetrical structure. For inner rotor motor, the periodic symmetric constructions that serve as sound sources are stator core. For outer rotor motor, it is outer rotor. Although it is necessary to clarify the resonance condition of an inner and outer rotor motors to reduce noise, the condition when the resonance happens has not become clear enough yet. In this paper, the resonance condition of the inner rotor motor is applied to the outer rotor motor, focusing on the difference of the coordinate system of the periodic symmetric structure as a sound source. In addition, the theoretical results of this paper are used to explain the experimental results of outer rotor motor, and it is verified the proposed resonance condition.