| 摘要 |
PURPOSE:To always operate a commutatorless motor in a preferable power factor by dividing the induced voltage of a synchronous motor in 2-axis voltages to obtain the inner phase difference angle of the motor, and shifting the phase of a set control leading angle of an inverter in response to the difference. CONSTITUTION:The output of an inverter 2 is detected by a voltage/current detector 12, the output is inputted to an induced voltage calculator 15 to obtain the induced voltage of a synchronous motor 3. This induced voltage is, for example, divided into 2-axial voltages such as a component parallel to the pole and the component perpendicular thereto by a 2-axial induced voltage calculator 17, and the internal phase difference angle is obtained by an internal phase difference angle calculator 18. Then, the set control leading angle is obtained by beta0 calculator 19, and the firing signal of the phase corresponding to the set control leading angle is generated by a firing signal generator 20. This firing angle is fed to the inverter 2. |
