Improving the reliability of locomotive electrical power devices by enhancing contact joints
DOI:
https://doi.org/10.33216/1998-7927-2025-294-8-30-38Keywords:
reliability, electrical power devices, locomotives, contact joints, electromagnetic contactors, contact resistance, international standards, innovative materials, composite materials, nanostructured materialsAbstract
In modern railway transport, the reliability of electrical power devices is a key factor in ensuring the safety and efficiency of locomotive operation.. The uninterrupted performance of systems such as traction motors, converters, and protection relays directly influences the stability of train movement and passenger safety.
Among the critical components of these systems are electrical contact joints, which are commonly used in switching devices such as contactors and circuit breakers. These joints are regularly subjected to significant electrical and mechanical stresses, including high current switching, thermal cycling, and vibration, all of which contribute to contact wear and eventual failure.
The degradation of contact surfaces leads to increased contact resistance, reduced conductivity, and a higher likelihood of arc formation, ultimately compromising the overall functionality of the power system. Therefore, improving the durability and electrical performance of contact joints is an essential objective in the development of more reliable locomotive power systems.
This study focuses on identifying effective strategies to improve contact joint reliability by analyzing contact materials, modeling key operational parameters such as contact resistance and failure probability and evaluating modern material technologies. Particular attention is given to the use of composite and nanostructured materials, which offer enhanced mechanical strength, erosion resistance, and compliance with international environmental standards.
To overcome the limitations associated with large-scale experimental testing, the research relies primarily on analytical methods supported by data from existing literature. This approach allows for the theoretical assessment of material performance and the identification of optimal solutions for practical implementation in railway systems.
Contact components used in the switching of electrical circuits have a significant impact on the performance and reliability of this equipment. This paper presents a study aimed at improving the operational reliability and mean time between failures of locomotive traction electromagnetic contactors by enhancing the stability of their contact characteristics. Due to the high cost and complexity of conducting large-scale experimental research, the emphasis is placed on analytical methods and the study of the properties of the materials used, proposing potential improvements based on available technologies and materials in accordance with international standards and current widespread innovations.
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