| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem that the fluctuation of direct current voltage influences the rotation state of a motor if the direct current voltage is not directed in an electric power circuit when the electrostatic capacity of the capacitor of an intermediate direct current part for small size and low cost is lessened in the three-phase motor drive circuit of single phase alternating current input. SOLUTION: The frequency and phase of the single phase alternating current input are detected, a regulation parameter group corresponding to the period of the half of a cycle is provided, the regulation parameter equivalent to an input voltage phase is minutely corrected when the voltage and current phase difference detection timing of the motor out of the regulation parameter group is obtained so that the phase difference between the current phase detection means of the motor and motor application voltage is equal to a set value, and the regulation parameter is used for the motor application voltage generation as a direct current voltage estimation value. |
