Experimental Analysis of a Variable-Speed Compressor

An experimental analysis of a variable-speed reciprocating compressor for household refrigeration, with an operating speed range of 2000 to 5000 rpm , is herein presented.The main parameters describing the compressor performance as a function of the shaft speed , are presented for a standard operating condition.A efficiency breakdown analysis is outlined.The motor characteristics and the inverter control system are discussed.It has been identified that the compressor efficiency at low speed, is penalized by the lower compression and motor efficiencies, while at the high speed the negative effects are the low mechanical and valve efficiencies.The maximum compressor efficiency stays around 60 Hz which corresponds to its original design speed.