Abstract: Aiming at the large instantaneous common-mode voltage in traditional space vector modulation strategy for two-stage matrix converter (TSMC), on the basis of analyzing the laws of common-mode voltage, an improved modulation strategy to reduce common-mode voltage was proposed. To suppress common-mode voltage effectively, in this strategy, the rectification stage sector was subdivided into twelve sectors from six sectors, according to the sector of the reference current vector and dc-side voltage, the switching points of inverter stage were redefined and reallocated, and zero vector of inverter was selected and distributed reasonably, instantaneous maximum value of common-mode voltage was reduced to 57.7% of the original value in TSMC, so negative effects were suppressed effectively. The feasibility and validity of the proposed method has been verified by simulation results.

Key words: TSMC, common-mode voltage, improved space vector modulation strategy, simulation