| 摘要 |
PURPOSE:To eliminate the need for the fitting of a dedicated pole-position sensor to the outside, and to miniaturize a device by overlapping a high-frequency signal to a motor drive signal, detecting flux change by a detecting without concentrically wound to a motor winding and obtaining a pole-position signal. CONSTITUTION:A high-frequency signal is overlapped to a current command by multioliers 22, 21 and subtractors 22, 23. A power amplifier feeds current according to the command to a winging Bypass filters (HPF) 24-27 lead out only the high-frequency signals from sensor winding voltage VS1-VS4. Multipliers 28-31 for multiplying HPF outputs by the same high-frequency signals as the overlapping ones to the current command, a subtractor 32 subtracting outputs from the multipliers 28 and 29, a subtractor 33 subtracting outputs from the multipliers 30 and 31 and low-pass filters 34, 35 for eliminating high-frequency components from outputs from the subtractors 32, 33 are mounted, and a pole-position signal is acquired. |
