机理-数据融合驱动的互联变流系统故障诊断方法  

Mechanism-data-fusion-driven Fault Diagnosis Method for Interconnected Conversion Systems

作　　者：石立国 李延真 李元付 关雪琳 徐志根 张明远 SHI Liguo;LI Yanzhen;LI Yuanfu;GUAN Xuelin;XU Zhigen;ZHANG Mingyuan(State Grid Shandong Electric Power Company Qingdao Power Supply Company,Qingdao 266000,Shandong,China;School of Electrical Engineering,Shandong University,Jinan 250001,Shandong,China)

机构地区：[1]国网山东省电力公司青岛供电公司,山东青岛266000 [2]山东大学电气工程学院,山东济南250001

出　　处：《电气传动》2024年第4期11-20,共10页Electric Drive

基　　金：国家电网有限公司总部管理科技项目(5100-202116567A-0-5-SF)。

摘　　要：三电平中点钳位型互联变流器,因其大容量、高电能质量等优势,已逐渐成为交直流混联配电网系统的主流能量变换装备。但其长期工作于大功率、时变负载、有限散热等恶劣工况,功率器件开路故障率高。同时,现有故障诊断方法多为单一机理或数据依赖,无法克服系统模型结构复杂、运行工况多变的难题,诊断准确性与快速性较差。为此,提出了一种机理-数据融合驱动的互联变流系统故障诊断方法。首先,基于三电平变流系统的机理模型,结合神经网络观测器,构建机理-数据融合模型以提高故障诊断精度。随后,分析了电流残差量在不同器件开路故障后的变化轨迹,总结出电流残差故障特征表进行开路故障诊断。最后,实验与硬件在环测试结果验证了所提方法的有效性。Three-level neutral-point-clamped(3L-NPC)interconnected converters have been widely used in the AC-DC hybrid distribution grids due to their superiorities of large capacity and high power quality.However,their working conditions are always with high power,varying load,and limited heat dissipation,etc.,with a high open-circuit failure rate of power switches.Meanwhile,existing fault diagnosis methods are mostly single mechanism-based or data-based,unable to overcome the problems of complex system model structure and changing operating conditions,resulting in low diagnostic accuracy and speed.To this end,a mechanism-data-fusion-driven fault diagnosis method for interconnected conversion systems was proposed.Firstly,a mechanism-data-fusion model was constructed using a neural network observer to improve the fault diagnosis accuracy.Subsequently,the trajectories of current residuals after open-circuit faults of different devices were analyzed,and a current residual table was summarized,based on which a fast and accurate open-circuit fault diagnosis method was formed.Finally,the experimental and hardware-in-the-loop results verify the effectiveness of the proposed method.

关 键 词：交直流混联配电网 三电平互联变流器 故障诊断 机理-数据融合 电流残差 

分 类 号：TM46[电气工程—电器]