| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the abnormal temperature increase of a field coil, when a power generating equipment wherein a rotating-field type AC generator is combined with an automatic voltage regulator is continuously operated at the number of revolution lower than a rating value. SOLUTION: A temperature detecting element Rth is thermally coupled with an MOSFET F1 constituting a switch 203 for field current control which turns on and off a field current If . The element Rth is connected in series with a resistor R6 constituting a part of a resistance voltage division circuit 204C of an output voltage detecting circuit 204 for detecting the output voltage of a generator 1. The value of an output voltage detecting signal V0 is set to exceed the value of a reference signal when the temperature of the MOSFET exceeds a set value. As a result, a switch control circuit 205 is operated and the MOSFET F1 is turned off when the temperature of the MOSFET exceeds the set value. Thus, the field current is cut off.</p> |
