Tubular Oil–Solid Triboelectric Nanogenerator Adopted for Self‐Powered Impurities Monitoring of Insulating Oil Flow

The advancement of the Industrial Internet of Things and digital‐intelligent machinery presents considerable demands in detecting impurities in industrial equipment lubricants or oils. Herein, a Tubular oil–solid triboelectric nanogenerator (TOS‐TENG) is designed as a self‐powered sensor for impurity detection in insulating oil flow. Specifically, an oleophobic triboelectric sensing layer with superior electron trapping capability is created based on Nano silica and 1H,1H,2H,2H‐perfluorodecyltriethoxysilane. Additionally, a periodic start‐stop oil flow control method that facilitates the transition between flowing and stationary insulating oil is proposed, thereby generating periodic output signals from the TOS‐TENG. Furthermore, a correlation between the output characteristics of the TOS‐TENG and impurity properties (type, content) is established through a deep learning algorithm based on convolutional neural networks, enabling the identification of common impurities such as moisture, metal, and fiber particles in oil. As a proof of concept, an industrial‐grade TOS‐TENG‐based device for in situ online monitoring of impurities in oil‐immersed transformers is designed. This work offers novel insights into the compositional analysis of continuous fluids and provides a novel strategy for oil condition sensing in smart industrial equipment.