Abstract:

 In order to reduce the vibration noise caused by motor in the system of coal preparation plant, we can reduce the vibration noise from motor ontology structure design and its material and control strategy aspects. According to the control strategy, the author presents a technology of random switching frequency which can spread spectrum of switching frequency and its times to reduce the harmonic amplitude. The author obtains the spectrum analysis diagram of SVPWM control strategy and random spectrum analysis diagram. Applying the random switching frequency PWM control strategy can obviously reduce the harmonic amplitude.