Novel Discontinuous Modulation Strategy for Z-Source Inverters Using Equal Time Interval Shoot-Through State Insertion Method

The conventional Z-source inverter shoot-through vector insertion method usually inserts a shoot-through vector between two different voltage vectors, which does not additionally increase the number of switching actions. However, the variation of the voltage vector dwell time will cause the fluctuation of the inductor ripple. In this paper, a modulation strategy with an equal time interval shoot-through vector insertion method is proposed. By utilizing the discontinuous modulation strategy and selecting lower switching loss shoot-through vectors, the reduction of inductor ripple is achieved with essentially no increase in losses. The effectiveness of the proposed modulation strategy is demonstrated by MATLAB/Simulink combined with PLECS simulation.