Helium management control system

A cryogenic refrigeration system for controlling supply of helium refrigerant, the system comprising:

• at least one compressor, the at least one compressor including a high pressure supply line and a low pressure return line, the at least one compressor supplying helium refrigerant;
• a plurality of cryogenic refrigerators, each comprising a reciprocating displacer, coupled to the at least one compressor to receive helium refrigerant from the supply line and return helium refrigerant to the return lines;
• a supply pressure sensor sensing supply pressure on the supply line;
• a return pressure sensor sensing return pressure on the return line;
• a system controller including:
• a helium refrigerant management system that receives communications from the plurality of cryogenic refrigerators, indicating demand for helium refrigerant and that determines an aggregated demand for the helium refrigerant for the plural cryogenic refrigerators;
• and
• a helium refrigerant supply correction controller that calculates a helium refrigerant supply correction based on a difference between sensed supply pressure and sensed return pressure and that computes amount of helium refrigerant to supply to the cryogenic refrigerators, based on the aggregated demand for the helium refrigerant corrected by the helium refrigerant supply correction;
• and
• a compressor controller that controls speed of the at least one compressor that delivers helium refrigerant to the plural cryogenic refrigerators to deliver the computed amount of helium refrigerant.

A method for controlling supply of a refrigerant, the method comprising:

• at a controller, obtaining an aggregated demand for a helium refrigerant based on communications from plural cryogenic refrigerators, each comprising a reciprocating displacer;
• and
• with the controller, controlling speed of a compressor of a plurality of compressors that deliver gas refrigerant to the plural cryogenic refrigerators, based on the aggregated demand for the refrigerant corrected by a refrigerant correction metric calculated based on supply and return refrigerant pressure;
• and
• turning a subset of the plurality of compressors on or off based on the aggregated demand for the refrigerant corrected by the refrigerant correction metric.

A refrigeration system for controlling supply of a refrigerant, the system comprising:

• a compressor of a plurality of compressors, the compressor of the plurality of compressors including a high pressure supply line and a low pressure return line, the compressor of the plurality of compressors configured to supply a helium refrigerant;
• a plurality of cryogenic refrigerators, each comprising a reciprocating displacer, coupled to the compressor of the plurality of compressors to receive helium refrigerant from the supply line and return helium refrigerant to the return lines;
• and
• an electronic controller configured to obtain an aggregated demand for the helium refrigerant based on communications from the plurality of cryogenic refrigerators, the electronic controller further configured to control speed of the compressor of the plurality of compressors based on the aggregated demand for the refrigerant corrected by a refrigerant correction metric, the correction metric determined based on a supply pressure feedback loop from the high pressure supply line and a return pressure feedback loop from the low pressure return line, the electronic controller being configured to turn a subset of the plurality of compressors that supply the helium refrigerant to the refrigerators on or off based on the aggregated demand for the refrigerant corrected by the refrigerant correction metric.