For the isolated three-phase DC-AC bidirectional converter

a zero-vector embedded space vector modulation strategy is proposed to improve the switching cycle utilization in order to optimize its current stress and conduction loss. The decoupling operation of the current vector is achieved by dynamically adjusting the internal duty cycle in the modulation waveform and embedding the zero level in each segment of the modulation waveform. Setting the modulation function related to the internal duty cycle

the converter can be classified into zero-vector-embedded operation mode and de-zero-vector-embedded operation mode according to the comparison result between the transmitted power and the minimum value of the modulation function. By constraining the internal duty cycle to satisfy the modulation function minimum condition

the modulation effectively reduces the zero-vector share of space current

improves the switching cycle utilization of the inductor current

and consequently reduces the peak and RMS values of the inductor current. This modulation strategy can achieve lower current stress and conduction loss compared to other space vector modulations. A prototype is built to experimentally test and compare the modulation

and it is verified that the proposed modulation strategy can improve the power conversion efficiency and reduce the current stress.