| 摘要 |
<P>PROBLEM TO BE SOLVED: To simultaneously detect a motor current and a motor electric angle, in a motor drive device which varies a PWM carrier frequency with a lapse of time. <P>SOLUTION: A carrier frequency changing part 8 changes the carrier frequency of PWM modulation with a lapse of time, and indicates a rectangular waveform phase adjustment part 15 to adjust the rise and fall timing of a rectangular waveform. A rectangular waveform generation part 16 generates a rectangular waveform at the adjusted phase. The rectangular waveform is supplied to an excitation coil 20 as a sine wave exciting signal via an LPF 6. An output of a detection coil 21 is detected by a resolver output signal detection part 13, and the electric angle is operated by a motor electric angle operation part 14. A carrier waveform generation part 9 simultaneously indicates the timing of sampling to a motor current detection part 11 and the resolver output signal detection part 13 at a valley of the carrier waveform. <P>COPYRIGHT: (C)2010,JPO&INPIT |
