Based on the fiber Bragg grating sensing principle, a surface-mount packaged fiber-optic partial discharge sensor is designed in this paper. The acoustic sensitive structure of the sensor is a circular silicon diaphragm, and the fiber grating is pasted on the surface of the diaphragm, which improves the detection sensitivity of the partial discharge of the transformer. Based on COMSOL, this paper analyzes the influence of the radius and thickness of the circular diaphragm on the first-order natural frequency and static pressure sensitivity. Through simulation, this paper selects the best size parameters and designs a circular silicon diaphragm structure with a first-order natural frequency in the range of 20kHz-60kHz. Pencil break experiment is carried out to study the frequency response of the sensor. Test in the partial discharge experimental platform to study the partial discharge detection performance of the sensor.

Partial Discharge,Fiber optic sensing,Fiber Bragg Grating