Feedback Control of Multiphase Induction Machines With Backstepping Technique

This article presents the control possibility of five-phase induction machines. In the proposed solution, the machine model vector form is not transformed to the (<italic>dq</italic>)-coordinate system, that is connected to the rotor flux vector, but utilizes the stationary system (α<italic>β</italic>). Moreover, the nonlinear model linearization is based on demonstrated nonlinear variables transformation for <italic>i</italic>-orthogonal <inline-formula><tex-math notation="LaTeX">$(\alpha \beta)_{(n)}$</tex-math></inline-formula> planes. By introducing the backstepping approach, the independent stabilization of electromagnetic torque and rotor flux in each plane is obtained. A practical stability analysis of the proposed controller for a multiphase machine is illustrated as well. Finally, experimental test results are demonstrated for a specific speed sensorless five-phase induction motor test setup.