SCREW COMPRESSOR SYSTEM AND OPERATING METHOD

摘要

PURPOSE: A screw compressor system and the operating method are provided to realize energy-saving operating by reducing shaft power of a screw compressor system equipped with plural screw compressors of a load and no-load operation type. CONSTITUTION: A screw compressor system comprises a plurality of screw compressors(A1,A2-An) controlling the capacities of the screw compressors by repeating load operation and no-load operation. The number of screw compressors to be operated in accordance with compressed gas consumption in a demander, is determined. The operating screw compressor performs load operation in all second screw compressors excepting one first screw compressor. A control unit changing discharge pressure of each of the first and second screw compressors in accordance with load factor of the first screw compressor is installed. The average operation pressure is lowered through automatic modulation of the range of discharge pressure of the compressor. Therefore, operation power is reduced and energy saving is possible.