Mechanical sensorless speed control of permanent-magnet AC motors driving an unknown load

C. DE ANGELO; G. BOSSIO; J. SOLSONA; G. GARCÍA; M. I. VALLA

IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS

IEEE

Año: 2006 vol. 53 p. 406 - 414

0278-0046

A new sensorless scheme for high-performance speedcontrol of permanent-magnet ac motors (PMACMs) driving anunknown load is proposed. This scheme uses an extended nonlinearreduced-order observer to estimate the induced electromotiveforce (EMF) and load torque. From the estimated variables, therotor position, the rotor speed, and the position derivative of  fluxare calculated and are used to close the control loop. In orderto improve the drive performance, the estimated load torque isincorporated as a feedforward signal in the closed control loop.In addition, the proposed sensorless PMACM drive allows thetorque-ripple and copper-loss minimization for motors with anarbitrary EMF waveform. Simulation and experimental results tovalidate the proposal are presented in this paper.