Novel prediction method of acoustic magnetic noise emitted by inverter-fed induction motor system

When an induction motor is driven by an inverter, the acoustic magnetic noise caused by the time harmonics of the motor input become a serious environmental problem. A novel prediction method of the acoustic magnetic noise emitted by an inverter-fed induction motor system is presented in this paper. Using this novel method, the acoustic magnetic noise vs. harmonic current characteristic function (NHCC function) is defined first, and then based upon this, the acoustic magnetic noise can be predicted by the calculation of the harmonic current of the motor. The principle of this method and the determination of the NHCC function are introduced. Some experimental results are also shown to verify the effectiveness of this novel method.