Operation results of reversible converters of AC electric locomotives VL80<sup>R</sup> on the Krasnoyarskaya Railway

Abstract

The article presents information about faults of reversible converters (RC) of AC electric locomotives of the VL80R series, fixed at the maintenance points of locomotives and locomotive depots of the Krasnoyarskaya Railway for the period 2014 – 2018. Authors provide data on the number of semi-conductor switches, their main parameters and technical characteristics for two types of converters — RC-2200 and RC-4000 operating on VL80<sup>R</sup> electric locomotives. Their influence on the RC construction scheme is shown. Revealed the causes of failures of the RC in the operation of electric locomotives. The role of maintenance of RC in electric locomotive and its monitoring system in ensuring reliable operation is shown as well as the statistical data on the quantitative and qualitative assessment of the types of failures of the RC. The article also shows statistics of changes in the number of converters of each type during the operation of electric locomotives. Information is given on the number of all faulty RCs on VL80R electric locomotives and an analysis of faulty RC-2200 and RC-4000s for a specified time period. The data is presented on the number of RC-2200 and RC-4000 failures per million km of the VL80<sup>R</sup> electric locomotive in terms of one section. Authors carried out analysis of statistics of this type of failure of the RC with reach-through breakdown of the shoulder. Information is given on the number of RCs with the reach-through breakdown of RC shoulders per million km of VL80R electric locomotives. It was concluded that for the period from 2014 to 2018, the number of failing RCs due to dangerous shoulder punctures decreased significantly, which led to a significant reduction in the number of failures of electric locomotives due to this failure. So, for RC-4000 this decrease occurred 5.75 times, and for RC-2200 2.4 times. In addition, the reason for a more significant reduction in the number of failures of electric locomotives with RC-4000 due to its faulty, is that RC-4000 is more modern and contains much fewer semi-conductor switches and additional elements. This increases the reliability of the RC. Thus, the replacement of obsolete RC-2200 with modern RC-4000 provided a reduction in the total number of faults of all RC in 2.3 times; decrease in the number of cases of RC failures per million km of a locomotive in 4 times.