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The purpose of this paper is to design an excellent
digital current controller which is the driver of the three-
phase AC induction motor. It is necessary to know the varia-
tion of the motor parameters and the information of the back e.
m.f. for the conventional current predictive controllers. The
controller in this paper is a current predictive control- ler
based on the linear prediction. Owing to the pretty short
sampling time, we can estimate the back e.m.f. by supposing
the deriation of the flux between two neighborhood sampling
times be zero. Furthermore, considering the variation of the
motor parameters, we can effectively predict the back e.m.f.
by linear prediction. The simulation and the experiment illu-
strate the results. The prediction coefficients not only
effectively estimate the variation of the back e.m.f. but
also reflect the variation of the motor parameters, i.e., the
controller is adaptive. The controller is simple and robust
enough. We need not to estimate the complex flex and the
motor parameters. The only information we must know is the
stator current. To de- crease the current harmonics and the
chopper energy loss, we use the best chopper pattern of the
inverter in the space ve- ctor modulation. The effect of the
short circuit prevention time is compensated. Furthermore,
the simulation illustrate the noise margin is good.
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