CN-121993940-A - Control method of liquid cooling unit of energy storage equipment and liquid cooling unit system

Abstract

The invention discloses a control method of a liquid cooling unit of energy storage equipment and a liquid cooling unit system. The energy storage device liquid cooling unit comprises a compressor, a condenser, an evaporator, an electronic expansion valve and a plurality of fans related to the condenser, wherein the control method comprises the steps of obtaining the ambient temperature, the high-pressure side pressure and the high-pressure side saturation temperature when the liquid cooling unit is in operation, starting at least one fan when the high-pressure side pressure is larger than a preset starting pressure threshold value, stopping all fans when the high-pressure side pressure is smaller than a preset stopping pressure threshold value, increasing or reducing the number of operating fans according to the current high-pressure side saturation temperature when the at least one fan is in operation, keeping the number of operating fans to be at least one fan to be in operation, and limiting the upper limit of the number of operating fans according to the current ambient temperature. The invention provides a control method and a control system for an energy storage liquid cooling unit, which are more accurate and can adapt to a wide environment temperature range, and can improve the reliability, stability and operation economy of heat management of an energy storage system.

Inventors

• WANG JIANFENG
• XU QIAN
• QIAN FANGLEI
• ZHOU SHIJIE
• LI MENGJIA

Assignees

• 宁波先锋智能科技有限公司

Dates

Publication Date

20260508

Application Date

20260210

Claims (10)

1. 1. The control method of the energy storage device liquid cooling unit comprises a compressor, a condenser, an evaporator, an electronic expansion valve and a plurality of fans associated with the condenser, and is characterized by comprising the following steps: Acquiring the ambient temperature, the high-pressure side pressure and the high-pressure side saturation temperature of the liquid cooling unit during operation; starting at least one fan when the high-pressure side pressure is greater than a preset starting pressure threshold value, and stopping all fans when the high-pressure side pressure is less than a preset stopping pressure threshold value; when at least one fan is operated, the number of the operated fans is increased or decreased according to the current high-pressure side saturation temperature and kept as one fan at least, and the upper limit of the number of the operated fans is limited according to the current environment temperature.
2. 2. The control method according to claim 1, wherein the number of fans is six or more, and wherein limiting the upper limit of the number of operating fans according to the current ambient temperature includes: Tenv-cur < Tenv1, the number of running fans is 1; Tenv1 < Tenv-cur < Tenv2, and the upper limit of the number of running fans is 2; tenv2 < Tenv-cur < Tenv3, the upper limit of the number of running fans is 3; tenv3 is less than or equal to Tenv-cur < Tenv4, and the upper limit of the number of running fans is 4; When Tenv4 is less than or equal to Tenv-cur, the upper limit of the number of running fans is 6; Wherein Tenv-cur is the current ambient temperature, tenv to Tenv4 are preset first to fourth ambient temperature thresholds.
3. 3. The control method according to claim 2, wherein the preset first ambient temperature threshold Tenv is-15 ℃ to-5 ℃, the preset second ambient temperature threshold Tenv2 is 0 ℃ to 10 ℃, the preset third ambient temperature threshold Tenv3 is 10 ℃ to 20 ℃, and the preset fourth ambient temperature threshold Tenv4 is 15 ℃ to 25 ℃.
4. 4. The control method according to claim 1 or2, characterized in that increasing or decreasing the number of operating fans according to the magnitude of the current high-pressure side saturation temperature includes: when T1 is less than or equal to Ts < T2, the number of running fans is reduced one by one; When T2 is less than or equal to Ts < T3, keeping the number of currently operated fans unchanged; When T3 is less than or equal to Ts < T4, the number of running fans is increased one by one; wherein Ts is the current high-side saturation temperature, and T1 to T4 are preset first to fourth temperature thresholds.
5. 5. The control method according to claim 4, wherein the preset first temperature threshold T1 is set to a value ranging from 20 ℃ to 30 ℃, the preset second temperature threshold T2 is set to a value ranging from 30 ℃ to 40 ℃, the preset third temperature threshold T3 is set to a value ranging from 35 ℃ to 45 ℃, and the preset fourth temperature threshold T4 is set to a value ranging from 40 ℃ to 50 ℃.
6. 6. The control method according to claim 4, wherein increasing or decreasing the number of operating fans according to the magnitude of the current high-pressure side saturation temperature includes: When Ts is less than T1, keeping the number of running fans to be 1; And when T3 is less than or equal to Ts < T4, the upper limit of the number of running fans is less than the maximum number of fans.
7. 7. The control method of claim 4, wherein the energy storage device fluid cooling unit comprises six fans arranged in two rows and three columns, wherein: when one fan is operated, one of the two fans in the second row is operated; when the two fans are operated, one fan is taken from the first row and the third row to operate; when the three fans are operated, one fan is taken from the first, second and third rows to operate; when the four fans are operated, two fans in the second row and one fan in each of the first row and the third row are operated; when five fans are operated, one fan in the second row and two fans in the first row and the third row are operated.
8. 8. The control method according to claim 7, wherein one of the two fans in the second row is turned on and off by the first switch, the other fan is turned on and off synchronously with the one fan in each of the first and third rows by the second switch, and the other fan in each of the first and third rows is turned on and off synchronously by the third switch.
9. 9. The control method according to claim 1, characterized in that the control method further comprises initial opening control of the electronic expansion valve according to the current ambient temperature, specifically comprising: if Tenv-cur is less than or equal to 0 ℃, setting the initial opening as a first opening value; If the temperature is 0 ℃ and is less than Tenv-cur and less than or equal to 35 ℃, setting the initial opening to be a second opening value; if the 35 ℃ is less than Tenv-cur and less than or equal to 45 ℃, setting the initial opening to be a third opening value; If Tenv-cur >45 ℃, setting the initial opening to be a fourth opening value; Wherein Tenv-cur is the current ambient temperature, the first opening value > the second opening value=the fourth opening value > the third opening value.
10. 10. A liquid cooling unit system, the liquid cooling unit system comprising: a refrigerant circulation loop including a compressor, a condenser, an electronic expansion valve, an evaporator, a temperature sensor and a pressure sensor; The fans are used for radiating the heat of the condenser; the controller is electrically connected with the pressure sensor, the temperature sensor, the electronic expansion valve and the fans; Wherein the controller is configured to perform the control method according to any one of claims 1 to 9.

Description

Control method of liquid cooling unit of energy storage equipment and liquid cooling unit system Technical Field The invention relates to the technical field of refrigeration, in particular to a control method of a liquid cooling unit of energy storage equipment and a liquid cooling unit system. Background With the rapid development of electrochemical energy storage technology, the liquid cooling unit has become a mainstream heat pipe understanding solution of a large-scale battery energy storage system due to the advantages of high heat dissipation efficiency, good temperature uniformity and the like. The liquid cooling unit continuously exports heat generated by the battery through refrigeration cycle, and ensures that the battery works in a safe and efficient temperature range. The heat dissipation efficiency of the condenser directly influences the operation energy efficiency and reliability of the whole unit, and the forced air cooling is usually carried out by matching a plurality of fans. In the existing control strategy of the energy storage liquid cooling unit, the start and stop and speed regulation of a fan are controlled based on a simple temperature or pressure threshold. One common method is to detect the temperature at the condenser outlet or compressor discharge, either to start the fan or to increase the fan speed when the temperature is above a certain set threshold, and to decrease the speed or to shut down the fan when the temperature is below another threshold. However, the existing control method has the defects that on one hand, the control has hysteresis and inaccuracy, the temperature of the exhaust port of the compressor is influenced by various transient factors, such as abrupt change of the running state of the compressor, disturbance of the ambient wind speed and the like, and the signal fluctuation is large. The control basis is directly used, so that the frequent start and stop or rotation speed oscillation of the fan is easily caused, the stability of the system is affected, and the energy efficiency is reduced. Meanwhile, although the pressure signal is relatively stable, the pressure signal is simply controlled by pressure, and cannot be directly related to a thermodynamic state which can reflect the heat exchange phase change nature, so that the control precision is limited. On the other hand, the operating environment temperature range of the energy storage power station is wide. Under the low-temperature environment, if the fan still operates at full speed according to logic designed based on the high-temperature working condition, the condensation pressure is too low, the normal operation of components such as an electronic expansion valve is affected, the system is unstable to operate, the electric energy of the fan is consumed unnecessarily, and the overall energy efficiency ratio of the system is reduced. Based on this, it is necessary to propose a technical solution to overcome the drawbacks of the prior art. Disclosure of Invention In order to overcome the defects of the prior art, the invention provides the control method and the system of the energy storage liquid cooling unit, which are more accurate and can adapt to a wide environment temperature range, and the reliability, the stability and the running economy of the heat management of the energy storage system can be improved. The invention is realized by the following technical scheme that the control method of the energy storage equipment liquid cooling unit comprises a compressor, a condenser, an evaporator, an electronic expansion valve and a plurality of fans associated with the condenser, and the control method comprises the following steps: Acquiring the ambient temperature, the high-pressure side pressure and the high-pressure side saturation temperature of the liquid cooling unit during operation; starting at least one fan when the high-pressure side pressure is greater than a preset starting pressure threshold value, and stopping all fans when the high-pressure side pressure is less than a preset stopping pressure threshold value; when at least one fan is operated, the number of the operated fans is increased or decreased according to the current high-pressure side saturation temperature and kept as one fan at least, and the upper limit of the number of the operated fans is limited according to the current environment temperature. As a further improved technical solution, the number of fans is six or more, where limiting the upper limit of the number of operating fans according to the current ambient temperature includes: Tenv-cur < Tenv1, the number of running fans is 1; Tenv1 < Tenv-cur < Tenv2, and the upper limit of the number of running fans is 2; tenv2 < Tenv-cur < Tenv3, the upper limit of the number of running fans is 3; tenv3 is less than or equal to Tenv-cur < Tenv4, and the upper limit of the number of running fans is 4; When Tenv4 is less than or equal to Tenv-cur, the upper limit of the