Maintenance Enhancement of the Performance of Aged Voltage Transformers Using Nanoparticles

This work proposes a new voltage transformer (VT) maintenance approach for restoring the oil’s insulation properties depending on the nanoparticles’ advantages. For the first time, a real-aged VT was used for the experimentation. Different experimental tests were performed and assessed on VT to ensure the effectiveness of the proposed technique, such as breakdown voltage (BDV), dissipation factor (DF), and insulation resistance (IR) tests. The experimental tests of VT were carried out before and after the treatment and compared with the new oil to prove the feasibility and robustness of the proposed technique. The experimental tests of VT were examined according to IEC standards. Based on the results, a significant improvement in the oil’s BDV and the insulation performance of the VT was conducted, indicating the substantial impact of nanoparticles for enhancing the maintenance of aged VT. The results indicated a significant improvement in the BDV of the oil and the insulation performance of the VT. Furthermore, a statistical analysis tool is used to assess and evaluate the accuracy of the experimental test. In addition, the
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-nearest neighbors (KNNs) classifier was conducted to diagnose and predict the state of the VT, the fine KNN developed 100% classification accuracy compared with 96.7% accuracy for the coarse KNN classifier. The recorded experimental measurements and the numerical results emphasize that the proposed method provides superior features.