| 摘要 |
FIELD: electricity.SUBSTANCE: rectifier unit for electric locomotive excitement (RUELE) consists of the rectifier diodes, IGBT transistor unit and diode for excitement current continuity maintenance. RUELE is connected to the voltage transformer and powers the excitement windings of motors. IGBT module protection circuits consist of the additional low-power transformer the primary winding of which is connected to the secondary winding of the traction transformer of electric locomotive. Two secondary windings are connected by one of leads to RUELE feeding winding, and by another lead to IGBT module collector through series connected diode and the additional controllable electronic switch. The protection method consists in that the most part of energy of leakage inductances at disabling of the module is taken away from its collector to the secondary winding of the additional low-power transformer. Activation of additional switches occurs depending on the half-cycle of mains voltage, at the moment not later than at disabling of IGBT module, and the disabling - depending on duration of switching overvoltage.EFFECT: switching overvoltage protection of rectifier unit for electric locomotive excitement.2 cl, 3 dwg |
