Implementation of phase disposition modulation method for the three-level diode-clamped matrix converter

To improve the input and output waveform quality in terms of total harmonic distortion (THD) for the three-level diode-clamped matrix converter topology, the phase disposition carrier-based modulation method is a good option. However, it is difficult to implement because of the loss of zero-current commutations. Aiming at addressing the problem above, a hybrid switching sequence for the phase disposition method is presented to realise the safe commutation, and a prediction-based method is used to alternate the switching sequences. The current direction information of the switches in cascaded rectifier for commutations is obtained by a current reconstruction method. As demonstrated by experimental results, the phase disposition method contributes to lower input and output waveforms THD values compared with the phase opposition disposition method.