An Online Diagnosis Method for Locomotive Inverter Open Circuit Fault Based on Voltage Analysis

Abstract

The invention discloses a locomotive inverter open-circuit fault online diagnosis method based on voltage analysis. The method includes the steps of establishing a fault judgment contrast table basedon voltage on the basis of output voltage signals of a locomotive inverter control circuit, a three-phase modulating principle and a fault generating mechanism, wherein the fault judgment contrast table comprises the correspondence of two-phase output voltage ratio signals and fault phase and the correspondence of voltage variation signals and fault positions; obtaining corresponding voltage ratiosignals and voltage variation signals when a locomotive inverter operates and fails; searching the fault judgment contrast table through the voltage ratio signals to determine the fault phase corresponding to a fault; searching the fault judgment contrast table under the fault phase through the voltage variation signals to determine the fault position corresponding to the fault, thereby realizingfault diagnosis. The locomotive inverter can be accurately and effectively diagnosed on the premise of not refitting a locomotive, the diagnosis cost is reduced, and the diagnosis efficiency is improved.

Description

technical field [0001] The invention relates to the related technical field of locomotive inverter fault diagnosis, in particular to an online diagnosis method for locomotive inverter open-circuit fault based on voltage analysis. Background technique [0002] Since the 1960s, semiconductor traction converter technology has been widely used in trains, and converter technology has become one of the symbols of locomotive advancement and reliability. With the popularity of converter technology, the failure of main circuit components has gradually become prominent. At present, nearly 38% of the converter system faults are directly or indirectly caused by the faults of semiconductor power electronic devices, most of which are open circuit faults, and the fault diagnosis systems installed in domestic EMUs, CRH, HXD and other models are mainly used for train operation Monitoring and recording have not fully realized the online self-diagnosis function of the train, and it is necessa...

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Problems solved by technology

[0004] The above research results have their own advantages in a specific working environment, but considering the following particularities of the locomotive, there may be the following shortcomings: 1) The equipment on the locomotive has been solidified, and it is not allowed to modify it at will to obtain system control signals or install locomotives The method of additional sensors is no longer applicable, and the fault diagnosis of the locomotive converter system must be based on non-intrusive constraints to have practical value; 2) The load on the locomotive has a large range of changes and changes frequently, and some methods use current as the diagnostic variable May lead to misdiagnosis

[0005] Therefore, in the process of implementing the present application, the inventor found that the prior art has at least the following defects: the current fault diagnosis for locomotive inverters is difficult to achieve accurate and effective diagnosis without modification

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