轻量化特征融合的CenterNet输电线路绝缘子自爆缺陷检测

Insulator self-explosion detection in transmission line based on CenterNet fusing lightweight features

输电线路智能化巡检是新一代电力系统建设的必然要求。当前,基于深度学习的检测模型由于参数量过大,使得利用无人机(UAV)进行边缘部署较困难。为使无人机可搭载轻量级模型实现输电线路中具有自爆缺陷绝缘子的识别,提出了一种轻量级CenterNet-GhostNet的目标检测网络。对模型主干特征提取网络进行轻量化处理,利用计算成本较低的GhostNet提取自爆缺陷绝缘子的多层次特征,降低模型复杂度;引入增强感受野模块(RFB)增强特征表达能力,提升模型对小目标特征信息的注意力;构建特征融合模块,将低层特征信息和高层特征信息有效融合以输出更完整的特征图,提高缺陷识别精度。利用迁移学习参数共享,结合冻结与解冻训练相结合的模型训练策略,缓解网络因小样本数据集而产生的泛化能力不足问题。基于构建的输电线路自爆缺陷绝缘子数据集对所提方法进行验证,实验结果表明:相比原始CenterNet,所提方法的AP50、AP75和AP50:95分别提升至0.86、0.74和0.63,模型参数量由124.61×10^(6)减少至64.2×10^(6),可实现复杂环境下的自爆缺陷绝缘子检测,提高了基于无人机的输电线路巡检精度与速度。

Intelligent inspection of transmission lines is an inevitable requirement for the construction of a new generation of power systems.At present,the detection model based on deep learning has too many parameters,which makes it difficult to deploy unmanned aerial vehicles(UAVs) at the edge.In order to enable the UAV to carry a lightweight model to identify insulators with self-explosion defects in transmission lines,a lightweight CenterNetGhostNet target detection network was proposed.Firstly,the backbone feature extraction network of the model received lightweight treatment,and the multi-level features of insulators with self-explosion defects were extracted by using GhostNet with low computational costs,so as to reduce the complexity of the model.Then,the enhanced receptive field block(RFB) was introduced to enhance the ability of feature expression and enhance the attention of the model to the feature information of small targets.Finally,a feature fusion module was constructed to effectively fuse the low-level feature information and high-level feature information,so as to output a more complete feature map and improve the accuracy of defect recognition.The model training strategy of sharing transfer learning parameters and combining freezing and thawing training was used,so as to avoid insufficient generalization ability of the network caused by a small sample dataset.Based on the constructed dataset of insulators with self-explosion defects in transmission lines,the proposed method was verified.The experimental results show that compared with the original CenterNet,AP50,AP75,and AP50:95 of the proposed method are increased to 0.86,0.74,and 0.63,respectively,and the number of model parameters is reduced from 124.61 ×10^(6) to 64.2 ×10^(6).Therefore,the proposed method can detect insulators with self-explosion defects in complex environments and improve the inspection accuracy and speed of transmission lines based on UAVs.