Method and apparatus for equalizing oil between compressors

摘要

The method involves operating a low pressure compressor (1) and a high pressure compressor (2) at rotational speeds lower than nominal speeds of the compressors, where the rotational speed of the high pressure compressor is higher than the rotational speed of the low pressure compressor. The high pressure compressor maintains the rotational speed to be higher than that of the lower pressure compressor during acceleration or deceleration of the rotational speeds. An independent claim is also included for a thermodynamic device comprising a low pressure compressor.