This paper presents a novel V/f control method for
speed sensorless induction motor drives. The proposed method
keeps a constant steady-state stator flux in d axis by adding the
stator resistance compensation. And the speed accuracy is
improved by using the precise slip frequency compensation.
Besides, a novel oscillation suppression compensation method is
proposed to improve the stability and convergence rate of the
drive system both in motoring and regenerating operations. The
compensation is achieved by feeding both d-axis and q-axis
dynamic current to frequency with different feedback
parameters. In this paper, the linear model of this proposed
system is derived and analyzed to design proper feedback
parameters. In addition, the parameter sensitivities under the
proposed V/f controlled method are studied based on the
steady-state operating point analysis. The simulation and
experimental results based on 15kW and 2.2kW IM drive
systems are presented to confirm the validity the proposed
method.