Dynamic stator current sharing in quadruple three-phase induction motor drives

In this paper, a field oriented control scheme for torque and rotor flux regulation of a quadruple three-phase induction machine is presented. Each three-phase stator winding is independently supplied by a conventional three-phase inverter. The presented motor drive can be utilized in both medium and high power systems. Furthermore, owing to the intrinsic redundant structure, it can be employed for applications requiring a high degree of reliability, such as more electric aircraft. A specific machine model is developed by introducing a proper space vector transformation, suitable for the particular stator winding arrangement of the machine. Furthermore, by exploiting the degrees of freedom of the system, a technique for current sharing management among the four three-phase stator windings is presented. It allows the power flows of the machine to be controlled in a very flexible way. The modulation strategy of the four three-phase inverters is based on the principle of three-phase decomposition. The effectiveness of the presented control scheme is verified by means of numerical simulations.