General Inverter Modulation Strategy for Multi-Phase Motor Drives

In this paper the problem of the modulation strategy of a multi-phase voltage source inverter for high performance motor drives is completely solved using the duty-cycle space vector approach, which combines the multiple space vector representation, useful in modeling and controlling multi-phase machines, with traditional carrier-based pulse width modulation principle, suitable for multi-phase inverters. This approach leads to the definition of a general modulation strategy that fully exploits the input dc voltage and can be usefully utilized in multi-phase motor drives with improved torque density, as well as in multi-motor drives. The effectiveness of the proposed modulation strategy is verified by numerical simulations and some experimental results.