MAGNETIC BEARINGS, VARIABLE SPEED CENTRIFUGAL COMPRESSION AND DIGITAL CONTROLS APPLIED IN A SMALL TONNAGE REFRIGERANT COMPRESSOR DESIGN

摘要

While great strides have been made in HVACR technologies in recent years, significant improvements in energyefficiency, reliability and product life have been elusive in mid-range applications. In this 50-500 TR range, themost promising potential for significant energy reduction lies in compressor integrated part load efficiency (IPLV)improvements. Although large chiller efficiencies have benefited from technology improvements like packagedvariable speed drives, the far larger and less energy efficient mid-range market of rooftop packaged systems andsmaller chillers has yet to benefit from these centrifugal compression related efficiencies and other availabletechnologies. A nominal 60-90TR two-stage centrifugal oil-free R-134a refrigerant compressor utilizing integratedvariable speed drive, magnetic bearings and an onboard digital control system affords major advantages for mid-marketchiller and rooftop HVACR equipment.