| 摘要 |
<p>PURPOSE:To see that the current more than rated value does not flow to the thyristor of a field circuit at short circuit of a thyristor excitation system generator. CONSTITUTION:A commutation diode 12 connected to the same polarity as a thyristor 3 is provided, in parallel with the thyristor 3 between the terminals of the field winding 2 of an alteruator 1 which has a field circuit for converting the AC power of a three-phase transformer 4 into DC power through a thyristor 3 and exciting the field winding by this DC power. Furthermore, at short circuit of the alternator 1, a commutation diode is commutated by the voltage induced in the field winding 2 by the armature reaction of the alternator 1, and a current over rated value does not flow to the thyristor 3, so an economical field circuit can be obtained.</p> |
