抄録
Increasing interest in environmental matters, a quiet motor are drastically demanded lately. Among of acoustic noise of the motor, electromagnetic acoustic noise is jarring and is studied recently. Electromagnetic acoustic noise is strongly affected by (1) increase of magnetic density by reduction of motor size and (2) decrease of stiffness by right weight. In order to reduce electromagnetic acoustic noise, it is necessary to design the motor, of which natural frequencies of does not coincide with electromagnetic force frequencies. In order to avoid the resonance of the natural frequencies of the core and the electromagnetic force frequencies at designing phase, machine designer has to accurately predict these frequencies. In order to reduce the electromagnetic acoustic noise, this paper studies the following things, which are not clarified in previous research. Simulation method of the natural frequency in laminated steel sheet stator core
