Locomotive converter repairs

KONČAR – Electronics and Informatics has been refurbishing, repairing and testing the twenty diode rectifiers of the main drive and three converters of the auxiliary drives PJUT 135-D as part of the large and medium repair work of the seven diode locomotives of the 1141 series manufactured in the seventies and eighties of the last century.

The diode rectifiers are designed for supply of the traction motor of the locomotive with a DC voltage (885V, 1250A). In the process, the rectifiers are completely disassembled, cleaned in detail, mounting surfaces on semiconductor heat sinks are renewed, all electrical components are thoroughly tested and parts reassembled. The defective parts are replaced by new ones. The rectifiers have a specific construction that requires strict adherence to the procedure and order of the work. After assembly, complete check of the rectifier is performed.

The PJUT 135-D converter is a static converter that converts a 900V single phase voltage to 3x380V 135kW three-phase voltage and serves for supply of auxiliary locomotive drives (ventilation, compressor and other auxiliary drives).
The converters are also completely disassembled, their parts are cleaned in detail, electronic devices, modules and relays are separately tested, semiconductors, capacitors, resistors are tested on test devices and impregnation of transformers and reactors is renewed. After that all parts are mounted back into the converter and tested under full load.

The diode rectifiers and converters are ready for further long-term reliable locomotive operation after refurbishment, repair and testing.