The embodiment of the invention provides a two-level
inverter common-mode
voltage suppression method and
system, and the method comprises the steps: carrying out the Clark transformation of a three-
phase modulation wave, converting the three-
phase modulation wave from a three-phase static coordinate
system to a two-phase static coordinate
system, obtaining a current reference
voltage vector, and carrying out the Clark transformation of the current reference
voltage vector; determining a sector where the current reference
voltage vector is located by using the current reference
voltage vector and a sector division rule; according to the current reference
voltage vector, the sector where the current reference voltage vector is located and the
direct current side voltage of the two-level
inverter, the duty ratio of a
zero voltage vector and the duty ratio of an odd effective voltage vector to be selected are obtained; and according to the duty ratio of the
zero voltage vector and the duty ratio of the odd effective voltage vector to be selected, generating a corresponding PWM driving waveform to drive an
inverter switching tube. The common-mode voltage can be effectively suppressed, sector selection of the reference voltage vector is reduced, the calculation amount is reduced, and the method is easier to implement.