CN-122015382-A - Cold accumulation cascade instant freezer system and control method thereof

CN122015382ACN 122015382 ACN122015382 ACN 122015382ACN-122015382-A

Abstract

The invention discloses a cold accumulation cascade instant freezer system and a control method thereof, wherein the cold accumulation system comprises a cold accumulation unit, a cold accumulation condenser, a first expansion valve and a cold accumulation device which are sequentially connected through pipelines to form a cold accumulation loop, the instant freezer system is sequentially connected with the instant freezer unit, the cold accumulation device, a second expansion valve and an instant freezer evaporator which are sequentially connected through pipelines to form an instant freezer loop, the instant freezer evaporator is arranged in a heat preservation warehouse body, the cold accumulation device comprises an ice pool with a built-in phase change medium, the ice pool is used as the cold accumulation evaporator in the cold accumulation system to solidify and accumulate the phase change medium, and the ice pool is used as the instant freezer condenser in the instant freezer system to melt and release the phase change medium. The invention utilizes night valley electricity to store cold, peak electricity releasing cold in daytime to assist quick freezing, greatly reduces electricity cost and saves energy consumption, and compared with the scheme that the existing cold storage temperature is lower than the quick freezing temperature, the cold storage device has higher cold storage temperature, the energy consumption of the cold storage device is lower, the cold storage temperature is decoupled from the quick freezing temperature, and the cold storage device is not limited by the latter and is more flexible to apply.

Inventors

WANG PU
CHENG MING
LV PENGYU
YU XIAOFENG
ZHANG MINGFA
QI FENG
MA LINA
LI HAOLONG

Assignees

北京大学南昌创新研究院
北创碳启科技(江西)有限公司

Dates

Publication Date: 20260512
Application Date: 20260401

Claims (10)

1. A cold accumulation cascade instant freezer system, comprising: the cold accumulation system is sequentially connected with the cold accumulation unit, the cold accumulation condenser, the first expansion valve and the cold accumulation device through pipelines to form a cold accumulation loop; The quick-freezing system is sequentially connected with a quick-freezing unit, a cold accumulation device, a second expansion valve and a quick-freezing evaporator through pipelines to form a quick-freezing loop, and the quick-freezing evaporator is arranged in the heat-preserving warehouse; the cold accumulation device comprises an ice pool with a built-in phase change medium, the ice pool is used as a cold accumulation evaporator in a cold accumulation system to solidify and accumulate cold of the phase change medium, and the ice pool is used as a quick-freezing condenser in a quick-freezing system to melt and release cold of the phase change medium.
2. The cold accumulation cascade instant freezer system of claim 1, further comprising: The state monitoring module monitors the temperature of an ice pool in the cold accumulation device, the temperature in the heat preservation warehouse body, the temperature and the pressure of the refrigerant in the cold accumulation loop and the temperature and the pressure of the refrigerant in the quick freezing loop; And the mode control module is used for switching control modes according to the data monitored by the state monitoring module and the peak-valley time period, wherein the control modes comprise a cold accumulation mode, a quick freezing mode and a combined operation mode.
3. The cold accumulation cascade instant freezer system according to claim 1 or 2, wherein a pre-cooler is arranged on a pipeline between the instant freezer unit and the cold accumulation device in the instant freezer circuit.
4. The cold accumulation cascade instant freezer system according to claim 1 or 2, wherein in the cold accumulation loop, a first gas-liquid separator is arranged on a pipeline between the cold accumulation device and the cold accumulation unit; In the quick-freezing loop, a second gas-liquid separator is arranged on a pipeline between the quick-freezing evaporator and the quick-freezing machine set.
5. The cold accumulation cascade instant freezer system according to claim 1 or 2, wherein a first temperature sensor and a first pressure sensor are arranged in the cold accumulation loop near the refrigerant inlet of the cold accumulation device, and a second temperature sensor and a second pressure sensor are arranged near the refrigerant outlet of the cold accumulation device; A third temperature sensor and a third pressure sensor are arranged at the position, close to the refrigerant inlet of the cold accumulation device, in the quick freezing loop, and a fourth temperature sensor and a fourth pressure sensor are arranged at the position, close to the refrigerant outlet of the cold accumulation device.
6. The cold accumulation cascade instant freezer system of claim 5, wherein a fifth temperature sensor and a sixth temperature sensor are respectively arranged in the ice pool near the inlet and the outlet of the refrigerant, and a seventh temperature sensor is arranged in the thermal insulation warehouse.
7. A control method of a cold accumulation cascade instant freezer system, which is applicable to the cold accumulation cascade instant freezer system as claimed in any one of claims 1 to 6, and is characterized by comprising: starting a cold accumulation mode in a valley electricity period, and enabling the ice pool to serve as a cold accumulation evaporator in a cold accumulation system to solidify and accumulate cold for the phase change medium; Starting a quick-freezing mode under the condition of quick-freezing requirement, wherein the ice pool is used as a quick-freezing condenser in a quick-freezing system to melt and cool the phase-change medium, so as to provide low-temperature condensation conditions for a quick-freezing loop and quick-freeze the goods in the thermal insulation warehouse; In the quick-freezing mode, the combined operation mode is started when the combined operation condition is met, and cold accumulation and quick freezing are simultaneously carried out.
8. The method for controlling a regenerative-cascade instant freezer system of claim 7, wherein the regenerative mode comprises: Controlling the operation parameters of the cold accumulation mode to enable the refrigerant entering the cold accumulation device to be in a supercooled liquid state and the refrigerant exiting the cold accumulation device to be in a superheated gaseous state; The temperature of the ice pool is monitored in real time, and the state of a refrigerant entering and exiting the cold accumulation device in the cold accumulation loop is monitored; and when the heat exchange temperature difference between the ice pool and the refrigerant is monitored to be smaller than the first temperature difference threshold value and the evaporation temperature of the cold accumulation loop is monitored to be lower than the second temperature threshold value, judging that cold accumulation is completed.
9. The method for controlling a cold accumulation cascade instant freezer system according to claim 7 or 8, wherein the instant freezing mode comprises: Controlling the operation parameters of the quick-freezing mode to enable the refrigerant entering the cold accumulation device to be in a superheated gaseous state and the refrigerant exiting the cold accumulation device to be in a supercooled liquid state; providing a low-temperature condensation source for the quick-freezing loop by maintaining the ice pool in an ice-water mixture state; The temperature of the ice pool and the heat preservation warehouse body is monitored in real time, the state of the refrigerant entering and exiting the ice pool in the quick-freezing loop is monitored, and when the combined operation condition is met, the combined operation mode is entered.
10. The method for controlling a cold storage cascade instant freezer system of claim 9, wherein the combined operating conditions comprise: the temperature in the ice pool exceeding a first temperature threshold, or The temperature fluctuation range in the heat preservation warehouse body exceeds the preset fluctuation threshold value, or The temperature of the refrigerant entering the cold accumulation device or leaving the cold accumulation device in the quick-freezing loop exceeds a preset percentage threshold value relative to the fluctuation of the steady operation time value.

Description

Cold accumulation cascade instant freezer system and control method thereof Technical Field The invention relates to the technical field of instant freezers, in particular to a cold accumulation cascade instant freezer system and a control method thereof. Background At present, the traditional Freon single-stage or double-stage compression refrigeration systems (such as a Han Zhong Shanji double-stage unit LT-S-83/41, LT-S-65/32 and the like) are commonly adopted in the food quick-freezing industry. Although these systems can meet basic refrigeration demands, there are problems of high running energy consumption, high electricity cost, and aggravated grid load during peak electricity consumption periods. The method can not realize peak shifting and valley filling by utilizing electricity price difference, so that the overall operation economy is poor. Meanwhile, in the prior art, the scheme of combining the cold accumulation technology with refrigeration equipment also exists, but the schemes also have great limitations, such as placing a cold accumulation medium subjected to cold accumulation and goods in the same cold storage to quickly freeze the goods, or directly using cold accumulation cold quantity in an auxiliary cold storage for cooling. These techniques require that the cold storage temperature must be below the target quick-freeze temperature, so that the cold storage temperature is limited to the quick-freeze temperature of the quick-freeze system, while also greatly increasing the cold storage energy consumption at low cold storage temperatures. The cold accumulation type instant freezer disclosed in Chinese patent literature has the publication number of CN206803578U and the publication date of 2017-12-26. The cold accumulation type instant freezer comprises a box body with a horizontal upper cover, wherein a refrigerating system, a cold accumulation mechanism and an air cooling circulation mechanism are arranged in the box body, the refrigerating system and the air cooling circulation mechanism are connected with a control system, the cold accumulation mechanism comprises a net basket, a cold accumulation container is arranged in the net basket, a cold accumulation agent is arranged in the cold accumulation container, the air cooling circulation mechanism comprises two wind wheels which are diagonally arranged in the box body, the wind wheels are respectively connected with an alternating current motor through a coupling, and the alternating current motor is arranged on the outer side of a heat insulation layer of the box body. In the technology, after the cold storage medium is precooled, the cold storage medium and the goods are stacked in the same space, cold air flows through the cold storage medium and the goods to refrigerate, but the quick-freezing mode requires the cold storage temperature to be far lower than the quick-freezing temperature of the goods, and the quick-freezing temperature cannot be controlled stably and accurately. Disclosure of Invention The invention provides a cold accumulation cascade instant freezer system and a control method thereof, which aim to solve the problems that cold accumulation temperature is limited by the quick freezing temperature of a quick freezing system and must be lower than the quick freezing temperature when quick freezing is carried out in the prior art, so that cold accumulation energy consumption can be greatly increased under the condition of low cold accumulation temperature. In order to achieve the above purpose, the present invention adopts the following technical scheme: A cold accumulation cascade instant freezer system comprising: the cold accumulation system is sequentially connected with the cold accumulation unit, the cold accumulation condenser, the first expansion valve and the cold accumulation device through pipelines to form a cold accumulation loop; The quick-freezing system is sequentially connected with a quick-freezing unit, a cold accumulation device, a second expansion valve and a quick-freezing evaporator through pipelines to form a quick-freezing loop, and the quick-freezing evaporator is arranged in the heat-preserving warehouse; the cold accumulation device comprises an ice pool with a built-in phase change medium, the ice pool is used as a cold accumulation evaporator in a cold accumulation system to solidify and accumulate cold of the phase change medium, and the ice pool is used as a quick-freezing condenser in a quick-freezing system to melt and release cold of the phase change medium. The cold accumulation cascade instant freezer system mainly comprises a cold accumulation system and a quick freezing system which are overlapped, wherein the cold accumulation system and the quick freezing system are coupled through a shared cold accumulation device, and the core aims to utilize night valley electricity to accumulate cold and release cold energy in a quick freezing working period in daytime to reduce condensati