1results about How to "Improve DC voltage utilization" patented technology

The application discloses a zero common-mode voltage modulation method, a unit and a magnetic suspension bearing control device, and belongs to the technical field of magnetic suspension bearing control. The method comprises the following steps: calculating a normalized differential-mode voltage instruction and a common-mode voltage instruction; judging a sector number according to the differential-mode voltage instruction; calculating the normalized action time of each voltage vector according to the sector number, the differential-mode voltage instruction and the common-mode voltage instruction; calculating four duty cycles according to the normalized action time of each voltage vector, and then distributing the four duty cycles to four bridge arms according to the sector number N to generate corresponding modulation signals; and comparing the set carrier signal and the modulation signals of the four bridge arms by using a carrier comparison link to generate a PWM signal, so as to drive a magnetic bearing driving converter. The application can significantly inhibit the common-mode electromagnetic interference caused by the magnetic suspension bearing controller without affecting the normal control of the magnetic suspension bearing, and can avoid the damage to the protection bearing and the influence on the displacement sensor.