A System Using Fluorescent Fiber for Partial Discharge Detection in Transformer

It is a new method to monitoring partial discharge(PD) signals by optical effect.. PD generated physical phenomena of optical effect and fluorescence optical fiber sensing certain wavelength of the light signal characteristics, so we developed a system using fluorescent fiber sensors for detecting PD signals. This paper introduced the principle of optical signal caused by PD detected by fluorescent fiber, and it also gave out the main parameters and the system components of sensors. We can set up a test platform to simulate the PD in transformer oil in the laboratory. Compared to the test results measured by ultrahigh frequency method, we can get the conclusion that the PD pulses detected by these two methods mainly occurred around the positive and negative frequency voltage peak under the needle-plate defects in oil. Moreover, it had a good consistency in the number of discharge pulses and phases. The fluorescence optical fiber sensor can be easily embedded in transformer winding insulation, so it had a wide application prospect on the PD online monitoring in the complex insulation structure.