On steady state and dynamic performance of model reference control for a permanent magnet synchronous motor

Existing control strategies seldom explore the dynamic system characteristics of permanent magnet motors, relying upon the onset of current errors to detect and regulate current phase advance. Also, look-up table functions are the solution of steady state equations. For high performance motors with small time constants, insufficient voltage headroom is available at the onset of current error to allow movement of the current vector to its optimal position quickly enough, with resulting reduced torque output or instability. A model reference control method is proposed, which has a relatively small computational overhead, forms an appropriate basis for adaptive methods, and controls the system smoothly through the transition into the phase advance mode by extending the controller to utilise the dynamic system terms. The onset of phase advance is anticipated, the resulting voltage headroom allowing the model reference to retain control of the current vector