| 摘要 |
<p>PURPOSE:To make possible continuous control of field system and improve the comfortability of vehicles by changing the rate of field system through phase control of a reverse conducting thyristor or a reverse blocking thyristor and a diode put together by anti-parallel connection. CONSTITUTION:At the starting, with a reverse conducting thyristor 13 connected in parallel to a field winding 6 turned off, a constant current control is performed up to the maximum passage rate by the total field system. The moment the chopper reaches the maximum rate, it is fixed at its level, while the field rate is controlled through the phase control of the reverse conducting thyristor 13. With such an arrangement, in place of the conventional weak field switch, a thyristor element alone enables continuous control of weak field thereby bettering the comfortability of vehicles.</p> |
