| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric motor controller capable of controlling an electric motor to stably drive without using any position sensor in a range from a state a rotor is ceased to a state the rotor rotates at a high speed by precisely estimating the magnetic pole phase of the rotor.SOLUTION: The electric motor controller includes: a phase estimation section 6 that estimates the magnetic pole phase to output an estimated phase &thetas;s in a relatively low speed range; a magnetic flux estimator 8 estimates the magnetic pole phase to output an estimated phase &thetas;0 in a relatively high speed range; and a phase switching section 9 that directly switches the phase from the estimated phase &thetas;s to the estimated phase &thetas;0; or from the estimated phase &thetas;0 to the estimated phase &thetas;s at predetermined preset speed to output a phase signal &thetas;m. |
