| 摘要 |
<p>PURPOSE:To prevent a field coil or other electric device from burning out by using as a reference voltage a voltage proportional to the frequency in the range that the frequency of the generated voltage is lower than the set value and as the reference voltage the prescribed voltage when the frequency is equal to or higher than the set value. CONSTITUTION:A frequency/voltage converter 6 outputs a voltage proportional to the frequency of the generated voltage of a generator 1, a comparator 7 compares the prescribed voltage E from a variable resistor 9 with the output voltage V of the frequency/voltage converter 6, and outputs as the reference voltage Vf the lower voltage. An integrating amplifier 5 controls the current of the field coil 2b in response to the deviation voltage Vd between the reference voltage Vf and the generated voltage Vg of the generator 1. In this manner, the burnout of the field coil and the electric device can be prevented.</p> |
