Exact linearization of a linear PM brushless DC motor for artificial heart pump drive

This dissertation presents a nonlinear feedback control design methodology for a linear, permanent magnet brushless dc motor (LPMBDCM). A nonlinear state variable model for the motor is obtained and is subsequently transformed into a linear model by use of a diffeomorphism. Standard linear state space feedback control theory is applied in the new coordinate system and the resulting control law is then related back to the original coordinates. Although the control objective is a brushless dc motor with linear action, this methodology can be applied just as easily to rotary permanent magnet brushless dc motors. The dissertation also contains computer simulations of the resulting closed-loop system and a description of the experimental micro-processor based control system.