Synchronised Space-Vector Modulation for Six-Phase Automotive Drive with Controlled Switching Frequency

The paper presents results of analysis of operation of six-phase (dual three-phase) traction drive on the base of asymmetrical induction motor which has two sets of windings spatially shifted by 30 electrical degrees, and two three-phase inverters, supplied by two isolated DC sources (Fuel Cells + Battery). Novel control strategy for this drive topology is based on variation of switching frequencies of each inverter in dependence on the magnitudes of voltages of the corresponding DC sources. Basic schemes of synchronised pulsewidth modulation (PWM), applied for control of the two voltage source inverters with different switching frequencies, allow continuous voltage synchronization in systems and improved spectral composition of the phase voltages. Simulations show a behavior of the systems with continuous and discontinuous versions of synchronised PWM.