A method of diagnosing reversible converters of alternating current electric locomotives

Abstract

Failures of reversible converters (RCs) in ac electric locomotives can cause failures of ac locomotive power equipment. Depending on their severity, the electric locomotive can be placed in one of several different modes, from partial loss of function to complete halting. With this in mind, it becomes important to develop (upgrade) diagnostic support of RCs and decide on a procedure of diagnostics that would make it possible to identify defects of RCs not only in the running mode, but also in the stationary mode, during scheduled and unscheduled repairs of an electric locomotive. To provide a more reliable evaluation of the technical condition of the RC functional control, is necessary to check the connections between the converter parts. It is also important that the diagnostics allows modifications of input signals supplied to the converter inlet, depending on the results of a scheduled check for specifying the diagnosis and troubleshooting. The stationary automated diagnostics system makes it possible to determine the technical condition of an RC in the rectifier mode in stationary conditions and is intended for use in testing an RC exposed to simulated operational effects. In the current phase of development, the diagnostics system allows evaluation of the capacity and correctness of implementing the RC control algorithm in all four adjustment zones, as well as identification of RC leg interruptions. Together with the algorithm for RC diagnostics, the suggested method makes it possible to conduct functional tests and identify a particular defect, as well as check the operation of the RC by monitoring the work of the converter as a single diagnosed object before the RC is installed on the locomotive. This will ensure faster and more reliable diagnostics and make it possible to almost completely avoid the use of RCs with unidentified defects.