Direct Torque Control of Sensorless Induction Machine Drives: A Two-Stage Kalman Filter Approach

Figure 6

Experimental results for parameters estimation.

(a) Speed estimation

(b) Difference of speed estimation between EKF and TEKF

(c) Real rotor position and estimation

(d) Stator flux estimation by TEKF and EKF

(e) Real stator current and estimation (TEKF)

(f) Real stator current and estimation (TEKF)

(g) TEKF stator current error

(h) TEKF stator current error