초록 ▼

An apparatus and method for controlling a multi-compressor refrigeration system. The controller is designed to maintain a target temperature in a specified area. It achieves this goal by selecting compressor configurations which will maintain a target pressure on the common compressor suction line d

An apparatus and method for controlling a multi-compressor refrigeration system. The controller is designed to maintain a target temperature in a specified area. It achieves this goal by selecting compressor configurations which will maintain a target pressure on the common compressor suction line directing refrigerant into the compressors. As part of the process, the controller first establishes a record of the load handling capabilities of all useable configurations of the compressors. Then, periodically, it detects the current temperature and line pressure; selects a preferred configuration of compressors in accordance with a predetermined algorithmic function of the target pressure, the current line pressure, and the record of the load handling capabilities; and activates the preferred configuration if different from the currently active configuration. At at least one preselected time during the operation of an active compressor configuration the controller updates the record of load handling capabilities. This is done, in accordance with a predetermined algorithm, when the expected rate of change of the line pressure (determined by the record of load handling capabilities) does not match the actual rate of change while the active compressor configuration has been in use. The controller can also periodically float the target pressure by increasing the target pressure if the measured temperature is lower than the target temperature, and decreasing the target pressure if the measured temperature is higher than the target temperature.

대표청구항 ▼

In a method of controlling a refrigeration system having at least one refrigerator case wherein goods are stored, a refrigeration system for said cases including a plurality of compressors having a common compressor suction line directing refrigerant into the compressors, means for detecting the pre

In a method of controlling a refrigeration system having at least one refrigerator case wherein goods are stored, a refrigeration system for said cases including a plurality of compressors having a common compressor suction line directing refrigerant into the compressors, means for detecting the pressure in the compressor suction line, the initial steps of: selecting a target pressure for said compressor suction line; and establishing a record of the load handling capabilities of a multiplicity of configurations of said compressors; and the steps of periodically: detecting the current line pressure; selecting a preferred configuration of compressors in accordance with a predetermined algorithmic function of the target pressure, the current line pressure, and said record of the load handling capabilities; and activating said preferred configuration of compressors if different from the currently active configuration; and at at least one preselected time during the operation of an active compressor configuration: determining the expected rate of change of the line pressure while said active compressor configuration is in use, said determination being in accordance with said record of the load handling capabilities; determining the actual rate of change of the line pressure while said active compressor configuration has been in use; and updating said record of the load handling capabilities, in accordance with a predetermined algorithm, when said actual rate of change of the line pressure is not equal to said expected rate.