The Method for On-Line Monitoring of tan delta of Transformer Bushing Based on Conductor Temperature Distribution

摘要

On-line monitoring of dielectric loss factor of transformer bushing is of great significance to its safe and stable operation. However, on-line monitoring has problems of large disturbance and potential safety concerns. In this paper, a new method for on-line monitoring of dielectric loss factor of transformer bushing is proposed to overcome these problems. Optical fiber temperature measurement system is placed inside the conductor. According to relationship between the dielectric loss factor (tans) and conductor temperature distribution, the tans can be obtained by using finite element multi-physical field coupling method. This method is verified by the example of a 220 kV transformer bushing, and the error is less than 8%. This method is used to overcome the existing problems in on-line monitoring of dielectric loss factor.