Abstract: In a semi-anechoic chamber, by using PULSE sound and vibration acquisition system, noise output signals of different measurement points on a scale transformer model under different operation conditions are measured and analyzed. By comparing two standards of acoustic radiation power calculation between GB/T 1094.10—2003“Power transformers Part 10: Determination of sound levels” and GB6882—86“ten point sound power approach”, the effects of different boundary conditions on acoustic sound power measurements are studied. Experimental results show that firewall has some influence on acoustic radiation power transformer. Under different acoustic boundary conditions, results from two test standard are very close and within 1 dB mismatch. The methods described in standards GB / T 1094.10—2003 is very accurate and stable according to the study.

Key words: transformer, scale model, sound power, noise, firewall, low-frequency noise, sound pressure