基于多通道的二维递归融合图和LMCR模型的NPC型三电平逆变器故障诊断  

Fault Diagnosis of NPC-type Three-level Inverter Based on Multi-channel Two-dimensional Recursive Fusion Map and LMCR Modeling

作　　者：毕贵红[1] 王小玲 陈冬静 赵四洪 陈世语 陈仕龙[1] BI Guihong;WANG Xiaoling;CHEN Dongjing;ZHAO Sihong;CHEN Shiyu;CHEN Shilong(School of Electric Power Engineering,Kunming University of Science and Technology,Kunming 650500,China)

机构地区：[1]昆明理工大学电力工程学院,昆明650500

出　　处：《高电压技术》2025年第3期1269-1283,I0002,I0003,共17页High Voltage Engineering

基　　金：国家自然科学基金(51767012)。

摘　　要：中点钳位(neutral point clamped,NPC)型三电平逆变器并网工作环境恶劣,IGBT面临单管与双管同时故障的挑战,这使得故障特征之间的差异变得非常微弱,进而导致双管故障的识别精度难以有效提升。为此,提出了一种新的故障诊断方法,该方法结合了多通道的二维递归融合图和轻量化多尺度残差(lightweightmultiscale convolutional residuals,LMCR)网络。首先,通过仿真获取三相电流信号作为故障信号;再利用递归图(recurrence plot,RP)将三相电流信号分别转化为二维图并进行多通道融合,以捕捉时间序列中的周期性、突变点和趋势等特征;最后,将递归融合图作为输入,输入到LMCR模型中进行故障识别,LMCR模型整合多级Inception结构和残差网络,用于提取不同尺度的特征并融合这些特征,从而保证网络的梯度消失和爆炸。实验结果显示,该方法在IGBT故障识别中表现出色,无噪声环境下平均识别准确率达100%,噪声环境中也达到了92.53%,充分证明了该方法具有较强的特征提取能力和优异的抗噪性能。In the grid-connected operating environment of neutral point clamped(NPC)three-level inverters,IGBTs face the challenge of single-tube and dual-tube simultaneous faults,which makes the differences between fault features ex-tremely subtle and consequently hinders the effective improvement of dual-tube fault identification accuracy.To address this issue,this paper proposes a novel fault diagnosis method that combines multi-channel two-dimensional recurrence fusion plots and a lightweight multiscale convolutional residuals(LMCR)network.Firstly,three-phase current signals are obtained through simulation as fault signals.Then,recurrence plots(RPs)are utilized to convert the three-phase current signals into two-dimensional images,respectively,which are subsequently fused in a multi-channel manner to capture features such as periodicity,abrupt changes,and trends in the time series.Finally,the recurrence fusion plots are input in-to the LMCR model for fault identification.The LMCR model integrates multi-level Inception structures and residual networks to extract and fuse features at different scales,ensuring the mitigation of vanishing and exploding gradients in the network.Experimental results demonstrate that this method excels in IGBT fault identification,achieving an average accuracy of 100%in a noise-free environment and 92.53%in a noisy environment,fully proving its strong feature extrac-tion capability and excellent noise resistance.

关 键 词：NPC型三电平逆变器 开路故障 递归图 深度学习 多尺度特征 

分 类 号：TM464[电气工程—电器]