On-Line Monitoring of Power Transformer Core Vibration Test System Based on Optical Fiber Fabry-Perot Sensor and Photodetector

摘要

Transformer fault is a common problem in power system safety. In the situation of major failure of severe power transformers (PTF), the entire power grid system can be crashed and collapsed. In this study, by analyzing the causes of the vibration of transformer core (vTFC), it was found that the magnetostriction of the silicon steel sheet (SSS) is the main cause of vTFC. The magnetostrictive effect and principle of SSS was analyzed, and the relationship between core magnetostriction and exciting voltage, current, core vibration acceleration and core magnetostriction were discussed. Based on the optical fiber Fabry-Perot sensor (FFPs) and photodetector, vTFC signal testing system was designed as a whole. The system was built and the system was used to measure and analyze the vTFC signal. It is verified that the higher harmonic components of the vTFC signal are mainly distributed around the natural frequency of the core and will vary with the load. The test results showed that the system designed in this study is stable, it is capable of online monitoring and extracting effective vTFC signals, and is easy to optimize and upgrade.