Study on the workless forces in passivity-based control of induction motors

Based on the Euler-Lagrange equations and the induction motor model, the workless forces in passivity-based control of induction motors are analyzed in detail. The workless forces, which are generalized internal forces, can exist in the electromagnetic subsystem and the whole electromechanical system that is composed of the electromagnetic subsystem and the mechanical subsystem. The workless force in the electromagnetic subsystem is introduced by coordinate transformation and its physical meaning is the motional electromotive force (MEMF) that is caused by the interaction between stator and rotor by means of electricity and magnetic field. The physical meaning of the workless forces in the electromechanical system is the motional electromotive force and the electromagnetic torque that is caused by the interaction between the electromagnetic subsystem and the mechanical subsystem.