Static and Dynamic Evaluation of a Winding Deformation FBG Sensor for Power Transformer Applications

Area of Science:

• Electrical Engineering
• Materials Science
• Sensor Technology

Background:

• Power transformers are critical and costly assets in the electric power industry.
• Effective monitoring is essential for ensuring the reliability and longevity of power transformers.
• Fiber Bragg grating (FBG) sensors offer advantages as passive, dielectric elements for monitoring applications.

Purpose of the Study:

• To evaluate the performance of FBG pressure sensors for monitoring static and dynamic pressures in high voltage winding transformers.
• To assess the suitability of FBG sensors during transient events like short-circuits and inrush currents.
• To compare the performance of FBG sensors packaged with different materials: polyether ether ketone (PEEK) and transformerboard (TB).

Main Methods:

• FBG pressure sensors were developed and packaged using PEEK and TB materials.
• Static pressure tests were conducted within a specific force range (800 N to 1500 N).
• Dynamic impact tests simulating short-circuit conditions were performed, with time response analyzed using a 5 kHz interrogation system.

Main Results:

• FBG pressure sensors packaged with both PEEK and TB demonstrated suitability for transformer winding monitoring.
• PEEK-based sensors exhibited a static sensitivity of 0.911 pm/N, which was 4.47 times higher than TB-based sensors.
• Dynamic tests revealed excellent repeatability for both PEEK and TB packaged sensors, consistent with static observations.

Conclusions:

• FBG pressure sensors are a viable technology for monitoring high voltage winding transformers.
• The choice of packaging material (PEEK vs. TB) influences sensor sensitivity, with PEEK offering higher static sensitivity.
• Both PEEK and TB packaged FBG sensors provide reliable and repeatable measurements under static and dynamic conditions relevant to transformer operation.