| 摘要 |
PURPOSE:To complete a repair economically in a short pause period by using as a speed detector a low speed winding by supplying an AC of variable voltage and variable frequency to a high speed winding when repairing old existing AC 2-stage elevator. CONSTITUTION:3-phase AC power is converted by a converter 21 and a smoothing condenser 22 into a DC power, applied to an inverter 23, to become variable voltage and variable frequency AC power. This AC power is supplied to the high speed winding of a motor, a rotor 24 starts in the direction determined by the phase sequence of an input, and a cage 27 starts elevating. When a high speed winding 5 is energized and a rotor 24 is rotated, a low speed winding 6 generates a 3-phase AC voltage, and the magnitude is proportional to the rotating speed of a rotor 2X. This detecting output is controlled as a speed feedback signal. |
