Startup Logic For Refrigeration System

摘要

A refrigeration system (10) includes a compressor (20) having a first stage (20a) and a second stage (20b); a heat rejecting heat exchanger (40) having a fan (44) drawing ambient fluid over the heat rejecting heat exchanger, the heat rejecting heat exchanger including an inter-cooler (43) and a gas cooler(41), the intercooler coupled to an outlet of the first stage and the gas cooler coupled to an outlet of the second stage;, an unload valve (93) coupled to an outlet of the intercooler and a suction port of the first stage; a flash tank (70) coupled to an outlet of the gas cooler; a primary expansion device (55) coupled to an outlet of the flash tank; a heat absorbing heat exchanger (50) coupled to an outlet of the primary expansion device, an outlet of the heat absorbing heat exchanger coupled to the suction port of the first stage; and a controller (100) for executing a startup process.

主权项

1. A refrigeration system comprising:
a compressor having a first stage and a second stage; a heat rejecting heat exchanger having a fan drawing ambient fluid over the heat rejecting heat exchanger, the heat rejecting heat exchanger including an intercooler and a gas cooler, the intercooler coupled to an outlet of the first stage and the gas cooler coupled to an outlet of the second stage; an unload valve coupled to an outlet of the intercooler and a suction port of the first stage; a flash tank coupled to an outlet of the gas cooler; a primary expansion device coupled to an outlet of the flash tank; a heat absorbing heat exchanger coupled to an outlet of the primary expansion device, an outlet of the heat absorbing heat exchanger coupled to the suction port of the first stage; and a controller for executing a startup process including at least one of:
controlling the fan speed to reduce refrigerant heat loss in the heat rejecting heat exchanger;controlling the unload valve to direct refrigerant from the intercooler to the suction port of the first stage; andcontrolling the primary expansion device to restrict flow of refrigerant to the heat absorbing heat exchanger.