Various reduced common-mode voltage space vector modulation (RCMV SVM) methods have been proposed to reduce destructive common-mode voltage (CMV) in both voltage source converter (VSC) and current source converter (CSC) based motor drive systems. Most of them reduce the CMV by avoiding using zero-state vectors. Unlike CMV in VSCs which is related to constant dclink voltage, CMV in CSCs is related to AC side voltages which vary sinusoidally. Thus, zero-state vectors in CSCs can be selected, instead of being avoided, to reduce CMV.;In this thesis, three zero-state selection methods for CMV reduction in CSC based motor drives are proposed. Method 1 is CMV peak value reduction using independent approach, Method 2 is CMV peak value reduction using synchronized approach, and Method 3 is CMV average value reduction. Unlike the nonzero-state modulation methods, the proposed methods will not shrink the modulation index range or affect the harmonic performance. |