| 摘要 |
<p>PROBLEM TO BE SOLVED: To determine presence of layer short of a field winding surely without requiring any special processing of a synchronous motor under operation. SOLUTION: A layer short verifying unit comprises a variable DC and AC power supply section 6 for conducting a current through a field winding for an interval required for a synchronous motor to reach a rated rotational speed from stopping state, a filter section 7 receiving the input voltage, the input current and the r.p.m. when the field winding is conducting, an operating section 8 for calculating the impedance from the input voltage and current received from the filter section 7, a section 9 comparing the impedance fluctuation for the r.p.m. fluctuation calculated at the operating section 8, and a section 11 for outputting the comparison results.</p> |
