300mK adsorption refrigeration automatic cooling optimization control method based on CRC-GL7 refrigerator

Abstract

The invention discloses a 300mK adsorption refrigeration automatic cooling optimization control method based on a CRC-GL7 refrigerator. With the method, the fine control on the cooling process based on the CRC-GL7 refrigerator is realized, the judgment conditions of each stage of refrigeration are specified and quantified, a PID algorithm is designed in the control strategy of each stage, and thebehavior of each heating resistor in the system can be dynamically adjusted according to the refrigeration stage of the refrigerator. Actual measurement results show that the CRC-GL7 refrigerator canbe automatically cooled to 300 mK or below according to the control method provided by the invention. The shortest time from closing of a heat flow switch to cooling to the temperature of 300mK or below can be controlled within 2 hours, and the keeping time of the temperature at 300mK or below can be about 15 hours at the longest, so that the use efficiency of an experiment platform based on the CRC-GL7 refrigerator is improved.

Description

technical field [0001] The invention mainly relates to the low-temperature refrigeration engineering technology in the field of superconducting low-temperature detection, especially the adsorption refrigeration technology with the lowest temperature as low as 300mK or below. Background technique [0002] Along with the development of superconducting detection technology, sub-K low-temperature refrigeration technology is also constantly changing with each passing day. As the popularity of quantum technology continues to rise, there is a huge demand for low-temperature refrigeration equipment. Superconducting detection is inseparable from cryogenic cooling platforms, and different types of detectors have different superconducting transition temperatures. In addition, there are huge differences in the minimum temperature and low temperature holding time that refrigerators with different principles can achieve. For many superconducting detectors, the temperature of 3K-4K can m...

AI Technical Summary

Problems solved by technology

[0007] The guiding steps of CRC-GL7 refrigerator cooling control give 4 basic refrigeration processes for CRC-GL7 refrigeration, which has a macroscopic guiding effect on the actual control of this refrigerator for refrigeration, but it also has the following problems and deficiencies: (1 ) The steps described are basically generalized, and the degree of refinement and process quantification is not enough (for example, the conditions for judging that He4 liquefaction has been fully carried out in the guidance steps are not clear), and the actual operation cannot ensure that the temperature can be successful every time. Even if the ground drops below 300mK, it cannot guarantee that the low temperature maintenance time will be maintained for a long time (more than 10 hours).

(2) The description of the cooling process involved in the guidance steps is relatively general, and there is a lack of specific control process and optimal control method, which will cause the cooling operation process to take a long time and cannot guarantee that it will drop below 300mK within a limited time

(3) The described operation steps are relatively discrete and cumbersome, lack of overall control logic, the manual control cooling process is extremely error-prone, time-consuming and laborious, and very complicated

[0008] It is precisely the existence of these practical problems that the 300mK adsorption refrigeration platform based on the CRC-GL7 refrigerator is not efficient, which is a major defect as a complete set of refrigeration equipment

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