Title :
Passivity-based control of a class of Blondel-Park transformable electric machines
Author :
Nicklasson, Per J. ; Ortega, Romeo ; Espinosa-Pérez, Gerardo ; Jacobi, C.G.J.
Author_Institution :
SINTEF, Trondheim, Norway
fDate :
5/1/1997 12:00:00 AM
Abstract :
Concerns the extension to the general rotating electric machine model of the passivity-based controller method for induction motors. The motor´s passivity properties are used at 2 levels. First, we prove that the motor model can be decomposed as the feedback interconnection of two passive subsystems (essentially, the electrical and mechanical dynamics). Then, we design a torque-tracking controller that preserves passivity for the electrical subsystem and leaves the mechanical part as a passive disturbance. This leads to the cascaded controller structure which is typically analyzed involving time-scale separation. Our aim is to characterize a class of machines for which such a passivity-based controller solves the output feedback torque-tracking problem. The class consists of machines whose nonactuated dynamics are damped and whose dynamics can be decoupled. This requires that the air-gap magnetomotive force must be suitably approximated by the first harmonic in its Fourier expansion. These conditions have a clear physical interpretation in terms of the couplings between its dynamics and are satisfied by many machines. The passivity-based controller presented reduces to the well-known indirect vector controller for current-fed induction machines. Our developments constitute an extension to voltage-fed machines of this de facto standard in industrial applications
Keywords :
cascade control; electric machines; feedback; interconnected systems; machine control; machine theory; rotors; torque control; Blondel-Park transformable electric machines; Fourier expansion; air-gap magnetomotive force; cascaded controller structure; current-fed induction machines; damped nonactuated dynamics; dynamics decoupling; electrical dynamics; feedback interconnection; indirect vector controller; induction motors; mechanical dynamics; output feedback torque-tracking problem; passive subsystems; passivity; passivity-based control; rotating electric machine model; time-scale separation; torque-tracking controller; voltage-fed machines; Air gaps; Electric machines; Induction machines; Induction motors; Magnetic analysis; Magnetic separation; Output feedback; Standards development; Torque control; Voltage;
Journal_Title :
Automatic Control, IEEE Transactions on