Novel Overlap Method to Eliminate Vector Deviation Error in SVM of Current Source Inverters

The modulation signal of current source inverter contains an overlap instant to prevent interrupting the dc of the bulky input inductor. This overlap instant, located between vector states, results in output vector deviation errors which, in turn, leads to low-order harmonics in the output waveform. These harmonics are difficult to reject by the output filter. In this article, a novel modulation method is developed to realize zero-vector deviation error and, hence, eliminate the impact of the overlap instant. The ampere–second balance principle is applied to obtain the deviation error expression over the full range of the power factor angle. The mathematical expression of the vector deviation angle is derived in terms of the overlap time. Experimental results are provided to declare the effectiveness of the proposed modulation method.