METHOD OF SWITCHING OVERVOLTAGE PROTECTION OF RECTIFIER UNIT FOR ELECTRIC LOCOMOTIVE EXCITEMENT BASED ON IGBT MODULE AND RECTIFIER UNIT FOR ELECTRIC LOCOMOTIVE EXCITEMENT Russian patent published in 2015 - IPC B60L9/08 H02M7/12 

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 two additional traction transformer sections located in a single core and operating depending on the half-cycle of mains voltage. The sections by one lead are connected 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 additional secondary winding of the traction 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.

4 cl, 3 dwg