Oil Level Identification of Porcelain Cable Termination by Ultrasound

摘要

Based on the theoretical analysis about ultrasonic wave's reflection and refraction coefficient at ceramic-oil interface (COI) and ceramic-air interface (CAI), the paper studies the ultrasonic echo characteristics at COI and CAI of oil-filled porcelain cable termination(OFPCT) by experiments. The study shows that under the same condition, the first interface echo height of ultrasonic at COI is about 2dB higher than that at the COI, which can be easily inundated by defective coupling. However, the difference of the amplitude of echo attenuation and the echo times at two interfaces is relatively obvious. Based on the experimental result, the paper puts forward the ultrasonic method to detect oil level of OFPCT.