300 마력급 터보 압축기용 자기베어링의 설계 및 평가

Abstract

Recently, the international community is making steady efforts to reduce energy consumption to counter climate change and reduce CO₂ emissions. In view of this trend, there is a high interest in oil-free turbo compressors that are highly efficient in replacing conventional screw compressors and do not generate waste oil in the compressor field. In accordance with this trend, in the field of compressors, there is a high interest in oil-free turbo compressors which can replace existing screw compressors, have high efficiency and do not generate waste oil. In the case of an oil-free turbo compressor, magnetic bearings tend to be applied in a large amount, which has a high rotational stability at high speed and a load capacity capable of coping with a large axial thrust. In this study, magnetic bearings were designed to apply to a compressor of 300-HP and 50,000 rpm, and a rotor in the compressor were designed by direct drive method by applying a permanent magnet synchronous motor. After fabricating a 300-HP compressor with magnetic bearings, the motoring test under the no-load condition without impellers was performed up to 51,000 rpm to evaluate the structural stability against the centrifugal force of the rotating shaft. In addition, the rotational stability was evaluated by motoring test up to 50,000 rpm under the load condition with impellers. Based on the experimental results, it is presented that the hybrid magnetic bearings are suitable oil-free bearings capable of stably supporting turbo compressors.