| 摘要 |
PURPOSE:To stop the function, to partly limit and to indicate the defect of a rotary machine by providing DC voltage detecting means of a DC power source, current flow rate detecting means of controller and rotating speed detecting means of a rotor, and calculating the magnetic flux amount of a permanent magnet or the corresponding characteristic value. CONSTITUTION:A DC power source 1 is supplied to a converter 2, which drives a permanent magnet rotary machine 3. A control circuit 4 receives a signal of a position detector 5 which is mounted on the shaft end of the machine 3, and supplies a switching control current to the converter 2 through a gate circuit 6. The detection signals of a DC voltage detector 7 and a rotating speed detector 8 are applied to a circuit 4, which calculates the permanent magnetic flux amount of the machine 3 or the characteristic value corresponding to the magnetic flux amount, stops the controlling function on the basis of the calculated result, partly limits or indicate the defect or control the characteristic change. In this manner, the demagnetization of the permanent magnet at the normal operation time is detected to control as required. |
