变流器在线预诊断与健康管理关键技术研究

Power converters have been widely used in many areas, such as aviation and aerospace, military, metallurgy, transportation, electrical power and the generation of renewable energy. The reliability of the converter is crucial to ensure the safe and efficient operation of the systems. In order to improve the reliability of the systems during operation, there are increasing research attentions being paid to the Prognostics and Health Management (PHM) technology for power converter both from academics and industry. Currently, the research work is mainly focused on the failure mechanisms of power electronic devices and the prognostics technique based on the device parameter monitoring. However, all the power devices are packaged inside a converter, making it difficult to be accessed. This issue has become the bottle neck technique that practically limit the large scale application of the PHM technique in the realistic converter systems. This project will take use of the converter terminal variables which are convenient to monitor, to realize the online prognostics, residual life predication and health management for power converter. Firstly, the correlations between the various converter terminal variables (e.g. electrical, thermal and magnetic signals) and the vaiours devices failure modes and conditions will be investigated. Based on this, a simple and practical online monitoring system will be developed and the prognostics and residual life predication algorithms will be proposed. Finally, the converter operation, control and maintenance strategies will be adjusted based on the prognostics technique to realize the health management of the converter systems. This project aims to solve the key issue of converter reliability upgrading technology by developing a novel terminal testing method and theory. The research is expected to have significant impacts to the academics and industries.

变流器广泛应用于航空航天、军事、冶金、交通、电力以及新能源发电等众多领域，变流器可靠性对保障系统安全、可靠、高效运行至关重要。目前国内外正积极开展变流器故障预诊断与健康管理技术的研究，主要集中在功率器件故障机理以及基于器件参数监测的故障预诊断技术。然而变流器的封装结构使得内部器件参数测量十分困难，这已成为阻碍该技术大规模工业应用的瓶颈问题。为解决上述困难，本项目拟通过在线监测现成或方便可测的变流器端部变量实现故障预诊断、寿命预测和健康管理功能。课题组将首先研究变流器端部电、热、磁等各种变量与功率器件故障之间的基本关系；在此基础上开发简便、实用的变流器在线监测装置并研究故障预诊断与剩余寿命预测相关算法；最后将故障预诊断与变流器运行、控制及维护相结合，通过健康管理实现系统安全、可靠、高效运行。本项目将研究变流器运行可靠性关键技术及理论，研究思路新颖，具有重要理论意义与工程价值。

世界上大部分电能通过电力电子技术进行变换与控制，因此提高变流器（即电力电子装置）的运行可靠性具有十分重要的意义。项目实施期间，课题组按计划从变流器故障预诊断与健康管理的新角度开展了大量工作。为提高变流器运行可靠性，课题组提出了一系列简便、安全、有效的变流器测试、监测、诊断以及运行技术。主要研究内容包括：1）基于“端部变量”监测的变流器故障预诊断技术、2）变流器IGBT模块结温测量技术、3）基于开关频率动态控制的变流器延寿运行技术以及4）新能源发电现场测试技术。大量实验和仿真结果验证了这些方法的可行性与有效性。本项目的开展对相关技术的成熟与发展打下了良好基础。