| 摘要 |
PURPOSE:To detect induced voltage of a motor with small time lag and to enable immediate control, by a method wherein three resistors in Y-connection are connected in parallel to three-phase stator windings in Y-connection, and the potential difference between the neutral points of both is fed back. CONSTITUTION:Three resistors 21 in Y-connection are connected in parallel to three-phase stator windings 12 in Y-connection which are supplied with power from a three-phase inverter circuit 3. The potential difference between the neutral points of both is detected by a differential amplifier 22. A microcomputer 5 inputs speed command from outside or the induced voltage detection signal from the differential amplifier 22, and outputs control signal to a commutation control circuit 4. |
