Patent ID: 7628027
Filing Date: 2009-12-08
Classification: F25B

Abstract:
1. A refrigeration system comprising: a primary compressor receives refrigerant from an evaporator and delivers refrigerant to a condenser; a subcooling compressor delivers refrigerant to the condenser; a subcooler receives refrigerant from the condenser; a first refrigerant flow path through the subcooler, the first refrigerant flow path delivers a portion of the refrigerant to the evaporator; a second refrigerant flow path through the subcooler, the second refrigerant flow path delivers a remainder of the refrigerant to the subcooling compressor; a first sensor for measuring a first operating condition of the refrigeration system corresponding to a primary evaporating temperature; a second sensor for measuring a second operating condition of the refrigeration system corresponding to a condensing temperature; and a controller operable to control operation of the subcooling compressor, the controller varying operation of the subcooling compressor based upon the first and second operating conditions, the controller calculating a desired subcooler evaporating temperature required for highest efficiency operation of the refrigeration system based upon the primary evaporating temperature and the condensing temperature to maintain the subcooler evaporating temperature such that the refrigeration system operates at a point of highest efficiency.