| 摘要 |
PROBLEM TO BE SOLVED: To control a buried magnet motor with the maximum efficiency, without having to use rotary position sensors. SOLUTION: A rotary position θ and a rotary speed ω of the rotor of a brushless DC motor 12 are detected by a rotor rotation position detection port 13 and are supplied to a drive waveform generation part 14. Also, a torque T calculated by a torque calculation part 15 with load information as input is supplied to a current phase determination part 16 for performing the operation of an approximation expression for indicating a current phase β, to determine the current phase β, before supplying to the drive waveform generation part 14. Furthermore, a speed command value ω* being outputted from a speed control part 17 and an operation current I at an inverter 11 are also supplied to the drive waveform generation part 14. The drive waveform generation part 14 generates a PWM command, based on the input signals and supplies it to the inverter 11. |
