| 摘要 |
<p>PURPOSE:To obtain a brake circuit which does not decrease the commutation capacity to turn a main thyristor in a chopper OFF by connecting a main motor circuit of a railcar having an armature and a field winding in series with a main power source. CONSTITUTION:A main motor circuit 9 having an armature 10 and a field winding 11 is connected in series with a main power source, and a chopper 16 is connected in parallel with the power source. The chopper 16 has a series circuit of a crude thyristor151, a saturable reactor 163 and a commutation reactor 165, and a series circuit having an auxiliary thyristor 162, a saturable reactor 164 and a commutation capacitor 166. A series circuit of a brake thyristor 17 and a bypass resistor 18 is connected in parallel with the thyristor 161 and the reactor 163. Thus, when the thyristor 161 is commutated, a reverse voltage is applied to the thyristor 17 for brake until the reactor 163 is saturated.</p> |
