| 摘要 |
If there is static friction, the magnetic pole position estimation is completed at the time when error torque used for magnetic pole position estimation becomes less than the friction, so that there remains magnetic pole error. A problem has been that when the error torque becomes less than a forward static friction, there remains a positive magnetic pole deviation and when the error torque becomes less than a backward static friction, there remains a negative magnetic pole deviation. By shifting in the negative direction and the positive direction initial values for estimating a magnetic pole error in operation sets, a true pole-error estimation value is estimated in the use of a pole-error estimation value having a positive magnetic pole error obtained by the positive shift operation and a negative one obtained by the negative shift operation, which can reduce estimation error due to the static friction. |
