The causation of delays between channels, the source of error in estimation process, computer simulation and testing results about estimation process are also discussed.

Minimum Classification Error (MCE) criterion based sub-words weighting parameters estimation algorithm is proposed in which the sub-word weighting parameters are derived by the MCE training.

And electric steady also is introduced to estimation of rotor position, which solves effectively the problem of big error on rotor position estimation in process of dynamic.