Dual-system temperature control unit

Abstract

The utility model discloses a dual-system temperature control unit which comprises a tail end pipeline for exchanging heat with equipment to be subjected to temperature control, a fixed-frequency temperature control system and a variable-frequency temperature control system, the fixed-frequency temperature control system and the variable-frequency temperature control system are respectively subjected to heat exchange with the tail end pipeline, and the fixed-frequency temperature control system and / or the variable-frequency temperature control system are / is controlled to be opened or closed according to a temperature interval in which the temperature of an outdoor link is located; the fixed-frequency temperature control system adopts a fixed-frequency compressor, and the variable-frequency temperature control system adopts a variable-frequency compressor. According to the utility model, load control flexibility and environment temperature response reliability can be realized.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of refrigerating unit, especially a double system temperature control unit. BACKGROUND

[0002] The temperature control unit can adjust and control the working temperature and environmental temperature of indoor environment or equipment, thereby providing convenient conditions for people's home life or normal operation of equipment.

[0003] Taking an energy storage battery cabinet as an example, the working temperature of the battery in the energy storage battery cabinet has a direct impact on its performance and service life. Generally, the battery has a certain optimal working temperature range. Once the temperature exceeds the range, the charge and discharge efficiency of the battery will decrease significantly, and the risk of thermal runaway will increase. Therefore, the energy storage battery cabinet needs a high-efficiency and stable cooling system to accurately control the temperature of the battery, and the liquid cooling technology is widely used in this scenario.

[0004] The liquid cooling unit takes away heat through liquid circulation, has higher cooling efficiency and better temperature control accuracy compared to traditional air cooling systems, and is particularly suitable for high-power density and compact battery cabinet systems. The application of the liquid cooling unit in the energy storage battery cabinet mainly faces the following technical challenges:

[0005] The energy storage battery cabinet is usually deployed in outdoor or semi-outdoor environments and faces a wide range of environmental temperature changes from -30°C to 55°C. The operating stability of the liquid cooling system under extreme low and high temperature conditions becomes a key issue. In low temperature environments, the viscosity of the cooling liquid increases and the flowability decreases, which can easily lead to unstable cooling efficiency; in high temperature environments, the working load of the compressor and condenser increases, which can cause the refrigeration effect to decrease.

[0006] The heat generation inside the energy storage battery cabinet has periodic fluctuation characteristics, especially during frequent charging and discharging processes, the heat generated by the battery fluctuates significantly over time. This puts higher requirements on the water temperature control system of the liquid cooling unit, which must be able to quickly respond to temperature changes and maintain the stability of the water temperature. If not properly controlled, the periodic fluctuations in water temperature can further affect the temperature stability of the battery, thereby affecting the battery performance.

[0007] To cope with the high heat load of the energy storage battery cabinet, the liquid cooling unit is often equipped with a large-capacity compressor. However, under certain operating conditions (such as high ambient temperature), the energy efficiency of the compressor is not good, especially under partial load conditions, the energy efficiency further decreases. This situation can lead to an increase in the overall power consumption of the cooling system, reducing the operating economy of the energy storage system.

[0008] The heat load of the energy storage battery cabinet is dynamically changed, and the cooling demand is also constantly fluctuated with the change of the battery pack charging and discharging load. Although the fixed-frequency compressor has simple structure and low cost, it is difficult to adapt to the dynamic adjustment demand of the load due to the fixed power output. The variable-frequency compressor can flexibly adjust the operating power of the compressor according to the load condition, and has better adaptability, but the electrical system is complex and the cost is high.

[0009] In summary, although the application of the liquid cooling unit has obvious cooling efficiency and temperature control advantages, the existing technology still has certain limitations when facing the challenges of wide environmental temperature range and large dynamic load change.

[0010] Therefore, how to provide a double-system temperature control unit with flexible load control and good environmental temperature response reliability is a technical problem to be solved. Practical new type content

[0011] The utility model discloses in order to solve the technical problem that the temperature control system in the prior art cannot simultaneously consider flexible load control and good environmental temperature response reliability, and provides a double-system temperature control unit.

[0012] The double-system temperature control unit provided by the utility model comprises: an end pipeline for heat exchange with a temperature control equipment, a fixed-frequency temperature control system and a variable-frequency temperature control system for heat exchange with the end pipeline respectively, and the fixed-frequency temperature control system and / or the variable-frequency temperature control system are controlled to be opened or closed according to the temperature range of the outdoor link temperature.

[0013] The fixed-frequency temperature control system adopts a fixed-frequency compressor, and the variable-frequency temperature control system adopts a variable-frequency compressor.

[0014] Further, the water outlet of the first outlet pipeline of the first end heat exchanger of the fixed-frequency temperature control system is connected with the water inlet of the end pipeline, and the water inlet of the first inlet pipeline is connected with the water outlet of the end pipeline. The water outlet of the second outlet pipeline of the second end heat exchanger of the variable-frequency temperature control system is connected with the water inlet of the end pipeline, and the water inlet of the second inlet pipeline is connected with the water outlet of the end pipeline.

[0015] Further, an insulation water tank is arranged on the first outlet pipeline.

[0016] Further, a heater is arranged on the second outlet pipeline.

[0017] Further, when the temperature control equipment has a plurality of temperature control equipment, the temperature control equipment or the temperature control module for heat exchange with the temperature control equipment is connected in series in the loop formed by the end pipeline and the first end heat exchanger or the loop formed by the end pipeline and the second end heat exchanger, and sequentially exchanges heat with the heat exchange medium flowing through the end pipeline in the order of the temperature difference from small to large with the water inlet temperature of the end pipeline.

[0018] Further, the temperature-controlled equipment includes an energy storage battery cabinet and an electrical appliance box, and a temperature control module of the electrical appliance box is connected in series on a first inlet pipeline of the first terminal heat exchanger.

[0019] Further, outlet water ports of the first and second outlet pipelines are connected to inlet water ports of the terminal pipeline through a three-way proportional adjusting valve.

[0020] Further, the fixed-frequency temperature control system and the variable-frequency temperature control system share a double-system outdoor heat exchanger.

[0021] Further, a variable-frequency water pump is arranged at an outlet water port of the terminal pipeline.

[0022] Further, when the outdoor environment temperature is greater than the maximum value of the normal temperature range, the controller controls the variable-frequency temperature control system to be turned on, otherwise, the fixed-frequency temperature control system is preferentially turned on.

[0023] The double-system temperature control unit of the utility model has the advantages of the fixed-frequency temperature control system and the variable-frequency temperature control system, and the fixed-frequency temperature control system and the variable-frequency temperature control system are controlled to be turned on and turned off according to the environment temperature, so that the load control flexibility is realized, and meanwhile, the operation reliability under various environment temperatures is improved. When the double-system temperature control unit of the utility model is used to perform liquid cooling temperature control on the energy storage battery cabinet, the flexibility of the refrigerating unit to respond to the load during the operation of the energy storage system can be effectively improved, the fixed-frequency energy storage liquid cooling system is endowed with certain load adjustment capacity, the environmental adaptability and operation reliability of the energy storage liquid cooling unit are improved, and the cost is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0024] The utility model will be explained in detail in combination with embodiments and drawings, in which:

[0025] Figure 1 is the system schematic diagram of an embodiment of the utility model.

[0026] Figure 2 is the control flow chart of an embodiment of the utility model.

[0027] BRIEF DESCRIPTION OF DRAWINGS

[0028] 1, variable-frequency compressor;2, fixed-frequency compressor;3, double-system condenser;4, second electronic expansion valve;5, first electronic expansion valve;6, first plate heat exchanger;7, second plate heat exchanger;8, energy storage battery cabinet;9, electrical appliance box water cooling module;10, heat preservation water tank;11, three-way proportional adjusting valve;12, electric heater;13, variable-frequency water pump. DETAILED DESCRIPTION

[0029] In order to make the technical problems, technical solutions and beneficial effects of the utility model clearer and more apparent, the utility model will be further described in detail below in combination with the drawings and examples.

[0030] Therefore, one feature indicated in the specification will be used to explain one feature of one embodiment of the utility model, and it is not implied that each embodiment of the utility model must have the explained feature.

[0031] In order to solve the problem that the existing temperature control system cannot meet flexible load response, the double-system temperature control unit of the present application comprises a fixed-frequency temperature control system and a variable-frequency temperature control system, a terminal short circuit and a controller.

[0032] The fixed-frequency temperature control system is a refrigeration system or a heat pump system using a fixed-frequency compressor.

[0033] The variable-frequency temperature control system is a refrigeration system or a heat pump system using a variable-frequency compressor.

[0034] The terminal pipeline is connected to the fixed-frequency temperature control system and the variable-frequency temperature control system respectively, and after the medium of the fixed-frequency temperature control system and / or the variable-frequency temperature control system exchanges heat with the terminal pipeline, the medium exchanges heat with the temperature-controlled equipment.

[0035] The controller controls the fixed-frequency temperature control system and / or the variable-frequency temperature control system to open or close according to the temperature range of the outdoor link temperature.

[0036] The double-system temperature control unit of the utility model adopts two kinds of temperature control systems, i.e., fixed-frequency and variable-frequency, compared with a single fixed-frequency temperature control system, the flexibility of load response can be improved. Compared with a single variable-frequency temperature control system, the reliability of the unit under extreme working conditions is improved, and the operation cost of the double-system temperature control unit can also be reduced through the adjustment of the controller.

[0037] In one embodiment, the water outlet of the first outlet pipeline of the first terminal heat exchanger of the fixed-frequency temperature control system is connected to the water inlet of the terminal pipeline, and the water inlet of the first inlet pipeline is connected to the water outlet of the terminal pipeline.

[0038] This embodiment is only a specific pipe connection example, and the structure is relatively simple. In other embodiments, two sets of end pipes can be used to exchange heat with the first end heat exchanger and the second end heat exchanger, and both sets of end pipes exchange heat with the temperature-controlled equipment. Of course, in addition to the specific pipe connection examples listed in the utility model, those skilled in the art can also use other pipe connection structures.

[0039] In one embodiment, an insulation water tank is provided on the first outlet pipe. When the fixed-frequency temperature control system is a single refrigeration system, the insulation water tank is simply a cold storage tank. When the fixed-frequency temperature control system is a heat pump system, the insulation water tank can be a cold storage tank or a heat storage tank according to the application season.

[0040] The insulation water tank is provided in the fixed-frequency temperature control system, so that the fixed-frequency temperature control system also has a certain cold storage and heat storage capacity. Through the control of some valves, the stability of the liquid supply temperature can be controlled, so that the fixed-frequency liquid cooling system also has a certain load regulation capacity.

[0041] In one embodiment, a heater is provided on the second outlet pipe.

[0042] By adding a heater in the variable-frequency temperature control system, the unit can have a heat preservation operation function, and the water tank supply circuit of another fixed-frequency system is provided, so that the unit supply liquid temperature can be more stable and smooth.

[0043] In one embodiment, when the temperature-controlled equipment has multiple, the temperature-controlled equipment or the temperature control module in heat exchange with it is connected in series in the loop formed by the end pipe and the first end heat exchanger, or in the loop formed by the end pipe and the second end heat exchanger, and sequentially exchanges heat with the heat exchange medium flowing through the end pipe in order of the temperature difference from the inlet water temperature.

[0044] In order to improve the heat exchange efficiency, the utility model can exchange heat with multiple temperature-controlled equipment, and the temperature-controlled equipment with the smallest temperature difference from the inlet water temperature is preferentially exchanged, so as to reduce the temperature difference between the controlled equipment and the heat exchange medium, and improve the heat exchange efficiency.

[0045] In one embodiment, the temperature-controlled equipment includes an energy storage battery cabinet and an electrical box, and the temperature control module of the electrical box is connected in series on the first inlet pipe of the first end heat exchanger.

[0046] Energy storage battery cabinet is increasingly widely used in large-scale energy storage system, especially in grid peak shaving, renewable energy power generation and data center, etc. Efficient cooling of battery cabinet is the key to ensure the safe and stable operation of the system. Liquid cooling unit as the cooling equipment of energy storage battery cabinet undertakes the task of providing efficient heat dissipation for battery system to prevent battery pack from performance degradation, shortened life and even safety accidents caused by overheating during charging and discharging. When the energy storage battery cabinet needs to be cooled, the medium flowing through the terminal pipeline can further cool the electrical box after the terminal pipeline cools the energy storage battery cabinet, so as to improve the utilization rate of cooling capacity.

[0047] In one embodiment, the water outlets of the first and second outlet pipelines are connected to the water inlet of the terminal pipeline through a three-way proportional regulating valve.

[0048] When both the fixed frequency temperature control system and the variable frequency temperature control system are turned on, the three-way proportional regulating method can flexibly respond to the load demand and effectively meet the temperature needs of the temperature-controlled equipment.

[0049] In one embodiment, the fixed frequency temperature control system and the variable frequency temperature control system share a double-system outdoor heat exchanger.

[0050] Since there are usually size requirements for the double-system temperature control unit when controlling the temperature of the temperature-controlled equipment, using a double-system outdoor heat exchanger can effectively reduce the size of the outdoor unit of the double-system temperature control unit, meeting the size requirements of more application scenarios.

[0051] In one embodiment, the utility model is provided with a variable frequency water pump at the water outlet of the terminal pipeline. The installation position of the variable frequency water pump can also be other positions, such as the water inlet of the terminal pipeline. The utility model sets the variable frequency water pump downstream of the terminal pipeline, which can reduce the impact on the temperature-controlled equipment.

[0052] In one embodiment, when the outdoor environment temperature is greater than the maximum value of the normal temperature range, the controller controls the variable frequency temperature control system to be turned on, otherwise the fixed frequency temperature control system is preferentially turned on.

[0053] In this embodiment, when the outdoor environment temperature reaches the extreme temperature of overheating, only the variable frequency temperature control system is turned on to cope with extreme environments. Otherwise, the fixed frequency temperature control system is preferentially turned on, and when the temperature control of the fixed frequency temperature control system does not meet the demand, the heater and the variable frequency temperature control system are turned on to make up for it, so as to flexibly cope with different environment temperatures.

[0054] Figure 1 A specific embodiment of the utility model is given, in which the fixed frequency temperature control system includes a fixed frequency compressor 2, a double-system condenser 3, a first electronic expansion valve 5, a first plate heat exchanger 6, etc.

[0055] The variable frequency temperature control system comprises a variable frequency compressor 1, a double-system condenser 3, a second electronic expansion valve 4, and a second plate heat exchanger 7.

[0056] The double-system condenser 3 of the fixed frequency temperature control system and the variable frequency temperature control system is the same condenser, that is, the fixed frequency temperature control system and the variable frequency temperature control system share the same condenser.

[0057] Of course, in other embodiments, different condensers can be used respectively, but the space size of the entire temperature control system will be increased. In this embodiment, a double-system condenser is adopted because the application is in an energy storage battery cabinet, and the size of the liquid cooling unit has more stringent requirements.

[0058] The first plate heat exchanger 6 is the first end heat exchanger, and the second plate heat exchanger 7 is the second end heat exchanger.

[0059] An electric box water cooling module 9 is arranged on the first inlet pipeline of the first plate heat exchanger 6 for heat dissipation of the electric box.

[0060] A heat preservation water tank 10 is arranged on the first outlet pipeline of the first plate heat exchanger 6. Since the double-system temperature control unit is used for heat dissipation of the energy storage battery cabinet 8, in this embodiment, the heat preservation water tank 10 is mainly used for cold storage, which can also be called a cold storage water tank.

[0061] Further, the cold storage water tank can also be provided with a water tank heater to control the water temperature of the cold storage water tank.

[0062] At least one electric heater 12 is arranged on the second outlet pipeline of the second plate heat exchanger 7. The electric heater is used to heat the water when the water temperature is too low to cope with extreme environmental temperature.

[0063] The first outlet pipeline, the second outlet pipeline, and the end pipeline are connected through a three-way proportional regulating valve 11 to control the flow of the fixed frequency temperature control system and the variable frequency temperature control system into the end pipeline.

[0064] A variable frequency water pump 13 is arranged downstream of the energy storage battery cabinet 8.

[0065] The liquid supply circuit of the fixed frequency temperature control system is provided with the heat preservation water tank 10, and is also provided with pipeline electric heating and water tank electric heating, which can heat the water. Under normal circumstances, the cold water in the end pipeline is heated after heat exchange with the energy storage battery cabinet 8, but can still flow through the electric box water cooling module 9 for further heat dissipation, and then return to the first plate heat exchanger 6. After heat exchange in the first plate heat exchanger 6, the cold water flows into the heat preservation water tank 10, and the liquid supply flow is adjusted by the three-way proportional regulating valve 11, so that the fixed frequency temperature control system can provide relatively stable cooling capacity.

[0066] The liquid supply circuit of the variable frequency temperature control system is provided with an electric heater on the pipeline, which provides more flexible load adjustment capacity when the energy storage battery cabinet 8 has a small load.

[0067] The double-system temperature control unit has the advantages that, on the one hand, one of the double-system temperature control unit adopts a fixed-frequency compressor 2, which has a lower price and a more stable and long service life compared with a variable-frequency compressor 1, can guarantee the basic cooling capacity requirement of the energy storage liquid cooling unit, and reduces the unit operation failure rate; the fixed-frequency liquid cooling circuit is provided with a small heat preservation water tank 10, has a certain cold storage and heat storage capacity, and can control the stability of the liquid supply temperature by adjusting a three-way proportional regulating valve 11, so that the fixed-frequency liquid cooling system also has a certain load adjustment capacity.

[0068] On the other hand, the variable-frequency liquid cooling circuit gives the unit more flexible load response capacity, the liquid supply circuit is provided with an electric heater 12, so that the unit has a heat preservation operation function, and the liquid supply circuit of the other system water tank is provided, so that the liquid supply temperature of the unit can be more stable and smooth.

[0069] Figure 2 The control method of the double-system temperature control unit is shown.

[0070] The user can set the operation mode of the double-system temperature control unit in advance, and can select whether to manually operate or automatically operate.

[0071] If the user selects manual operation, the user can manually control the operating parameters of the double-system temperature control unit.

[0072] If the user selects automatic operation, the double-system temperature control unit automatically enters standby control, and after the double-system temperature control unit is started, the double-system temperature control unit has basic double-system and single-system functions, and has different control modes corresponding to different environmental temperature intervals.

[0073] In this embodiment, the environmental temperature interval is divided into three cases, which are: the environmental temperature is 0-45℃, the environmental temperature is -30℃-0℃, and the environmental temperature is 45℃-55℃.

[0074] When the environmental temperature is 0-45℃, the environmental temperature is the working temperature interval of the normal operation of the energy storage battery cabinet 8, the double-system temperature control unit is controlled to start and stop according to the double-system function, the fixed-frequency temperature control system is preferentially started, the three-way proportional regulating valve 11 is adjusted to meet the cooling capacity requirement, when the three-way proportional regulating valve 11 has reached the maximum opening or the minimum opening, and the liquid supply temperature cannot meet the cooling capacity requirement for a certain period of time, the three-way proportional regulating valve 11 is reset, the variable-frequency temperature control system is started, and the frequency of the variable-frequency compressor 1 is adjusted according to the target load.

[0075] When the ambient temperature is between -30 DEG C and 0 DEG C, the heat exchange load of the energy storage battery cabinet 8 is small, and heat preservation is needed, so the pure energy liquid cooling unit is automatically started in the heat preservation mode according to the water temperature, and the pipe electric heating and the water tank electric heating are used to supply warm water to the energy storage battery cabinet 8 to realize heat preservation, when the battery is started, the heat will accumulate quickly, and the heat load will increase rapidly, at this time, the pipe electric heating is closed, and the constant frequency temperature control system is started, which can quickly respond to the heat load demand, adjust the three-way proportional regulating valve 11, control the starting time of the water tank electric heating, and realize constant temperature liquid supply.

[0076] When the ambient temperature is between 45 DEG C and 55 DEG C, the heat exchange condition of the air side in the energy storage battery cabinet 8 is very poor, and the condition of restricting the heat exchange capacity of the unit is the condenser side (air side) heat exchange capacity, at this time, the variable frequency compressor 1 of the variable frequency temperature control system is preferentially opened, the condenser side fan runs at the maximum speed, the frequency of the variable frequency compressor 1 is adjusted according to the water temperature, and compared with the high-capacity single-system unit, the double-system unit can realize high-temperature and high-energy efficiency operation. In addition, since the electric appliance box water-cooled heat exchange module is additionally arranged, the unit can cool the electric appliance box at a higher temperature to maintain the stable operation of the system, and can ensure the refrigeration operation at 60 DEG C.

[0077] The above only describes the preferred embodiments of the utility model, and does not limit the utility model, and any modification, equivalent replacement and improvement made within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A dual system temperature control unit, characterized by, The application relates to a temperature control system for outdoor or semi-outdoor temperature-controlled equipment. The system comprises terminal pipelines for heat exchange with the temperature-controlled equipment, a fixed-frequency temperature control system and a variable-frequency temperature control system for heat exchange with the terminal pipelines, and a controller for controlling the fixed-frequency temperature control system and / or the variable-frequency temperature control system to be turned on or turned off according to the temperature interval of the outdoor environment temperature. The fixed-frequency temperature control system comprises a fixed-frequency compressor and a first terminal heat exchanger. The first outlet pipeline of the first terminal heat exchanger is connected with the water inlet of the terminal pipeline, and the first inlet pipeline is connected with the water outlet of the terminal pipeline. The variable-frequency temperature control system comprises a variable-frequency compressor and a second terminal heat exchanger.

2. The dual system temperature control unit of claim 1, wherein The second outlet pipeline of the second terminal heat exchanger is connected with the water inlet of the terminal pipeline, and the second inlet pipeline is connected with the water outlet of the terminal pipeline.

3. The dual system temperature control unit of claim 1, wherein, The first and second outlet pipelines are connected with the terminal pipeline through a three-way proportional regulating valve.

4. The dual system temperature control unit of claim 1, wherein A plurality of temperature-controlled equipment are connected in series on the terminal pipeline and are sequentially subjected to heat exchange according to the temperature difference from the water inlet temperature.

5. The dual system temperature control unit of claim 1, wherein A heat preservation water tank is arranged on the first outlet pipeline.

6. The dual system temperature control unit according to any one of claims 1 to 4, wherein A heater is arranged on the second outlet pipeline.

7. The dual system temperature control unit according to any one of claims 1 to 4, wherein The temperature-controlled equipment comprises an energy storage battery cabinet and an electric appliance box.

8. The dual system temperature control unit according to any one of claims 1 to 4, wherein The temperature control module of the electric appliance box is connected in series on the first inlet pipeline of the first terminal heat exchanger. The water outlet of the first and second outlet pipelines is connected with the water inlet of the terminal pipeline through a three-way proportional regulating valve. The fixed-frequency temperature control system and the variable-frequency temperature control system share a double-system outdoor heat exchanger. A variable-frequency water pump is arranged at the water outlet of the terminal pipeline. When the outdoor environment temperature is greater than the maximum value of the normal temperature interval, the controller controls the variable-frequency temperature control system to be turned on, otherwise, the fixed-frequency temperature control system is preferentially turned on.

Images