| 摘要 |
<p>A system is disclosed for generating the gate trigger voltage of thyristors connected in antiparallel and arranged parallel to the latching contact of an on-load change-over switch. Until now, the energy for the gate trigger voltage necessary to drive thyristor is taken either from outer voltage sources or from the regulating stage to be switched on via selected transformer taps. According to the invention, the voltage necessary to trigger the thyristors (8a, 8b, 9a, 9b) is generated by a permanent magnet (7) mechanically coupled to the movable contact (10) in triggering coils (2, 3, 4, 5) arranged in a magnetic circuit and supplied to the thyristors (8a, 8b, 9a, 9b). This system essentially increases the working reliability of the switch thanks to its independence from outer voltage sources and the prevention of unstable switching states caused by the frequent voltage interruptions that occur during a voltage drop in the regulating stage to be switched on, via selected transformer taps.</p> |
