Temperature control system for cooling battery and energy storage converter in parallel

Abstract

The utility model provides a temperature control system for cooling a battery and an energy storage converter in parallel, which relates to the technical field of electrochemistry and comprises a compressor, a plate heat exchanger, a first heat exchanger, a second heat exchanger, a first water pump and a second water pump. A cooling liquid channel outlet of the plate heat exchanger is communicated with a liquid supply port of the battery pack cooling liquid channel, and a liquid return port of the battery pack cooling liquid channel is communicated with a cooling liquid channel inlet of the plate heat exchanger through a first water pump; a compressor exhaust port communicates with a refrigerant channel inlet of the plate heat exchanger through the first heat exchanger, and a refrigerant channel outlet of the plate heat exchanger communicates with a compressor air inlet. An outlet of the second heat exchanger communicates with a liquid supply port of the energy storage converter cooling liquid channel, and a liquid return port of the energy storage converter cooling liquid channel communicates with an inlet of the second heat exchanger through a second water pump. The lithium battery pack and the energy storage converter are subjected to temperature control in two modes, the energy consumption of the temperature control system is saved by using a natural cold source, and the total energy consumption and the waste of the energy consumption are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of electrochemical energy storage, in particular to a temperature control system for parallel cooling of batteries and energy storage converters. Background Art

[0002] Renewable energy generation is gradually accounting for an increasing proportion of social electricity. Since photovoltaic, wind power and other renewable energy sources vary greatly with seasons and weather conditions, the introduction of energy storage technology can improve the mismatch between wind power, photovoltaic power generation and electricity load, and has therefore become an important part of energy planning. Energy storage technologies include pumped storage, compressed air, electrochemical energy storage and hydrogen energy storage. Among them, pumped storage and compressed air require suitable locations, while hydrogen energy storage is currently in the research stage. Electrochemical energy storage has entered the industry's field of vision and is gradually becoming an important energy storage technology.

[0003] Among the new energy storage technologies based on electrochemical energy storage, lithium-ion battery energy storage technology is the most widely used new energy storage technology. In energy storage systems, both lithium battery packs and energy storage converters (PCS) need to precisely control the operating temperature to avoid failures caused by exceeding operating conditions. In the existing technology, the lithium battery pack is generally fixed to the battery pack coolant channel, and the heat of the lithium battery pack is removed by the coolant in the battery pack coolant channel; the energy storage converter is fixed to the energy storage converter coolant channel, and the heat of the energy storage converter is removed by the coolant in the energy storage converter coolant channel. The battery pack coolant channel and the energy storage converter coolant channel are both connected to equipment such as compressors and heat exchangers to achieve temperature control.

[0004] However, the energy required for compressor cooling is very high, resulting in high energy demands. Furthermore, while existing temperature control systems can achieve temperature control, they share a common temperature control system, which means both the lithium battery pack and the energy storage inverter are controlled at the same temperature. In reality, the operating temperature requirement of the energy storage inverter is slightly lower than that of the battery pack. This also results in existing temperature control systems wasting energy on the energy storage inverter, failing to fully utilize energy for temperature control. Utility Model Content

[0005] The technical problem to be solved by the present invention is the problem of large energy consumption and waste in the temperature control of lithium battery packs and energy storage converters in the prior art. In order to overcome the above defects of the prior art, the present invention provides a parallel cooling battery and AC converter energy storage temperature control system.

[0006] The utility model provides a temperature control system for cooling batteries and energy storage converters in parallel, comprising a compressor, a plate heat exchanger, a first heat exchanger, a second heat exchanger, a first water pump and a second water pump;

[0007] The coolant channel outlet of the plate heat exchanger is connected to the liquid supply port of the battery pack coolant channel, and the return port of the battery pack coolant channel is connected to the coolant channel inlet of the plate heat exchanger through the first water pump; the exhaust port of the compressor is connected to the refrigerant channel inlet of the plate heat exchanger through the first heat exchanger, and the refrigerant channel outlet of the plate heat exchanger is connected to the air inlet of the compressor;

[0008] The outlet of the second heat exchanger is communicated with the liquid supply port of the cooling liquid channel of the energy storage converter, and the liquid return port of the cooling liquid channel of the energy storage converter is communicated with the inlet of the second heat exchanger through a second water pump.

[0009] Compared with the existing technology, the temperature control system of the present application for parallel cooling of batteries and energy storage inverters has the following advantages: the temperature of the lithium battery pack and the energy storage inverter is controlled in two forms to prevent excessive temperature from affecting operation, and the natural cooling source is used to save energy consumption of the temperature control system, fully utilize energy, reduce total energy consumption and reduce wasted energy consumption, saving energy and operating costs.

[0010] In one possible embodiment, the outlet of the first water pump is connected to the inlet of the coolant channel of the plate heat exchanger through a first ball valve, and the outlet of the second heat exchanger is connected to the liquid supply port of the coolant channel of the energy storage converter through a second ball valve; the outlet of the coolant channel of the plate heat exchanger is connected to the outlet of the second heat exchanger through a third ball valve, and the outlet of the first water pump is connected to the liquid return port of the coolant channel of the energy storage converter through a fourth ball valve; wherein, the first ball valve and the second ball valve are open, and the third ball valve and the fourth ball valve are closed; or the first ball valve and the second ball valve are closed, and the third ball valve and the fourth ball valve are open.

[0011] Compared with the existing technology, by controlling the opening or closing of four ball valves, the operation of different control pipelines is realized, which is convenient for temperature control of lithium battery packs and energy storage converters in high temperature and low temperature environments.

[0012] In a possible embodiment, a four-way valve is further included, which includes port a, port b, port c and port d; the outlet of the first water pump is connected to port a of the four-way valve, the port b of the four-way valve is connected to the liquid supply port of the coolant channel of the energy storage converter, the port c of the four-way valve is connected to the coolant channel inlet of the plate heat exchanger, and the port d of the four-way valve is connected to the outlet of the second heat exchanger; wherein, port a of the four-way valve is connected to port c of the four-way valve, and port b of the four-way valve is connected to port d of the four-way valve; or port a of the four-way valve is connected to port b of the four-way valve, and port c of the four-way valve is connected to port d of the four-way valve.

[0013] Compared with the existing technology, the operation of different control pipelines is achieved by controlling the connectivity of the four-way valve, which is convenient for temperature control of lithium battery packs and energy storage converters in high temperature and low temperature environments.

[0014] In a possible implementation, the outlet of the first heat exchanger is connected to the refrigerant channel inlet of the plate heat exchanger through an electronic expansion valve.

[0015] Compared with the existing technology, the flow opening is adjusted by setting an electronic expansion valve, which facilitates precise temperature control.

[0016] In a possible implementation manner, a first fan is provided on the first heat exchanger.

[0017] Compared with the prior art, the heat exchange effect of the first heat exchanger is improved by providing the first fan.

[0018] In a possible implementation manner, a second fan is provided on the second heat exchanger.

[0019] Compared with the prior art, the heat exchange effect of the second heat exchanger is improved by providing the second fan.

[0020] In a possible implementation, the coolant in the battery pack coolant channel and the energy storage converter coolant channel is water or ethylene glycol.

[0021] Compared with the existing technology, water acts as a solvent and catalyst, and ethylene glycol can increase the density and viscosity of the coolant and improve its heat transfer performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a working diagram of a first embodiment of a temperature control system for parallel cooling of batteries and energy storage converters according to the present invention;

[0023] Figure 2 This is a schematic diagram of a first embodiment of a temperature control system for parallel cooling of batteries and energy storage converters according to the present invention, operating under high ambient temperature;

[0024] Figure 3 This is a schematic diagram of the working state of a temperature control system for parallel cooling of batteries and energy storage converters in a low-temperature environment according to the first embodiment of the present invention;

[0025] Figure 4 This is a working diagram of a second embodiment of a temperature control system for parallel cooling of batteries and energy storage converters according to the present invention;

[0026] Figure 5 This is a schematic diagram of a second embodiment of a temperature control system for parallel cooling of batteries and energy storage converters according to the present invention, operating under high ambient temperature;

[0027] Figure 6This is a schematic diagram of a second embodiment of a temperature control system for parallel cooling of batteries and energy storage converters according to the present invention, operating under low ambient temperature.

[0028] Description of reference numerals:

[0029] 1-compressor; 2-plate heat exchanger; 3-first heat exchanger; 31-first fan; 4-second heat exchanger; 41-second fan; 5-first water pump; 6-second water pump; 7-battery pack coolant channel; 8-energy storage converter coolant channel; 91-first ball valve; 92-second ball valve; 93-third ball valve; 94-fourth ball valve; 95-four-way valve; 10-electronic expansion valve. DETAILED DESCRIPTION

[0030] First, those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the embodiments of the present application and are not intended to limit the scope of protection of the embodiments of the present application. Those skilled in the art may adjust them as needed to suit specific application scenarios.

[0031] In the description of the embodiments of this application, it should be noted that, unless otherwise specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of this application based on the specific circumstances.

[0032] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] Example 1

[0034] See also Figures 1 to 3 As shown, an embodiment of the present application discloses a temperature control system for parallel cooling of batteries and energy storage converters, including a compressor 1, a plate heat exchanger 2, a first heat exchanger 3, a second heat exchanger 4, a first water pump 5 and a second water pump 6.

[0035] The coolant channel outlet of the plate heat exchanger 2 is connected to the liquid supply port of the battery pack coolant channel 7, and the return port of the battery pack coolant channel 7 is connected to the coolant channel inlet of the plate heat exchanger 2 through the first water pump 5; the exhaust port of the compressor 1 is connected to the refrigerant channel inlet of the plate heat exchanger 2 through the first heat exchanger 3, and the refrigerant channel outlet of the plate heat exchanger 2 is connected to the air inlet of the compressor 1;

[0036] The outlet of the second heat exchanger 4 is connected to the liquid supply port of the energy storage converter coolant channel 8 , and the liquid return port of the energy storage converter coolant channel 8 is connected to the inlet of the second heat exchanger 4 through the second water pump 6 .

[0037] The temperature of the lithium battery pack and energy storage converter is controlled in two ways to prevent excessive temperature from affecting operation, and natural cooling sources are used to save energy consumption of the temperature control system, fully utilize energy, reduce total energy consumption and reduce wasted energy consumption, saving energy and operating costs.

[0038] In this embodiment, the outlet of the first heat exchanger 3 is connected to the refrigerant channel inlet of the plate heat exchanger 2 through an electronic expansion valve 10. By providing the electronic expansion valve 10, the flow opening can be adjusted to facilitate precise control of the cooling temperature.

[0039] The first heat exchanger 3 is provided with a first fan 31. The first fan 31 is provided to improve the heat exchange effect of the first heat exchanger 3.

[0040] The second heat exchanger 4 is provided with a second fan 41. By providing the second fan 42, the heat exchange effect of the second heat exchanger 4 is improved.

[0041] In this embodiment, the coolant in the battery pack coolant channel 7 and the energy storage converter coolant channel 8 is water or ethylene glycol. Water acts as a solvent and catalyst, while ethylene glycol can increase the density and viscosity of the coolant, improving its heat transfer performance.

[0042] In this embodiment, the outlet of the first water pump 5 is connected to the coolant channel inlet of the plate heat exchanger 2 through the first ball valve 91, and the outlet of the second heat exchanger 4 is connected to the liquid supply port of the coolant channel 8 of the energy storage converter through the second ball valve 92;

[0043] The outlet of the coolant channel of the plate heat exchanger 2 is connected to the outlet of the second heat exchanger 4 through the third ball valve 93, and the outlet of the first water pump 5 is connected to the return liquid port of the coolant channel 8 of the energy storage converter through the fourth ball valve 94;

[0044] The first ball valve 91 and the second ball valve 92 are open, and the third ball valve 93 and the fourth ball valve 94 are closed; or the first ball valve 91 and the second ball valve 92 are closed, and the third ball valve 93 and the fourth ball valve 94 are open.

[0045] By controlling the opening or closing of the four ball valves, the operation of different control pipelines is realized, which is convenient for temperature control of lithium battery packs and energy storage converters in high temperature and low temperature environments.

[0046] Specific: See Figure 1 and Figure 2 As shown, when the lithium battery pack and energy storage converter are operating in summer or in a place with very high ambient temperature, the first ball valve 91 and the second ball valve 92 are opened, and the third ball valve 93 and the fourth ball valve 94 are closed, starting the refrigeration cycle. The temperature control system is divided into two circuits, cooling the lithium battery pack and the energy storage converter respectively:

[0047] The high-temperature water / ethylene glycol solution in the battery pack coolant channel 7 exchanges heat with the refrigerant in the refrigeration cycle through the plate heat exchanger 2 under the action of the first water pump 5. The low-temperature coolant after heat exchange cools the lithium battery pack on the battery pack coolant channel 7 again, and the cycle continues;

[0048] The refrigerant in the refrigeration cycle exchanges heat with the coolant in the battery pack coolant channel 7 in the plate heat exchanger 2, absorbs heat, and evaporates to become a low-temperature, low-pressure gas. After passing through the compressor 1, it becomes a high-temperature, high-pressure gaseous refrigerant, enters the first heat exchanger 3, and is condensed into a high-temperature, high-pressure liquid by the first fan 31. The liquid refrigerant passes through the electronic expansion valve 10 and becomes a low-temperature, low-pressure liquid, which re-enters the plate heat exchanger 2, continuing the cycle.

[0049] Since the operating temperature range of the energy storage inverter is higher, a natural cold source is used to cool the energy storage inverter. The high-temperature return water passes through the second heat exchanger 4 under the action of the second water pump 6, and the temperature is reduced after heat exchange with the external air brought by the second fan 41. It is cooled again and enters the energy storage inverter coolant channel 8. The energy storage inverter coolant channel 8 cools the energy storage inverter thereon and circulates continuously.

[0050] See also Figure 1 and Figure 3 As shown, when the lithium battery pack and energy storage converter are operating in winter or in very low ambient temperatures, and the outside air temperature can meet the operating temperature requirements of both the battery pack and the energy storage converter, the first and second ball valves 91 and 92 are closed, while the third and fourth ball valves 93 and 94 are opened, starting the refrigeration cycle. The temperature control system is combined into a single loop, with the battery pack coolant channel 7 and the energy storage converter coolant channel 8 connected in series and sharing a common natural cooling system:

[0051] The high-temperature water / ethylene glycol solution flowing out of the energy storage inverter coolant channel 8 enters the second heat exchanger 4 under the action of the second water pump 6, and is cooled by heat exchange with the outside air guided by the second fan 41. Since the lithium battery pack is more sensitive to the operating temperature than the energy storage inverter, the low-temperature solution first enters the battery pack coolant channel 7 to cool the lithium battery pack on the battery pack coolant channel 7. After heat exchange, it becomes a lower temperature solution to cool the energy storage inverter. After heat exchange, it becomes a high-temperature solution and re-enters the second heat exchanger 4, and the cycle continues.

[0052] The two modes of this embodiment are switched by turning on and off four ball valves.

[0053] Example 2

[0054] See also Figures 4-6As shown, this embodiment is basically the same as the first embodiment, except that the first embodiment uses four ball valves for switching, while this embodiment uses a four-way valve 95. The four-way valve 95 includes a port a, a port b, a port c, and a port d;

[0055] The outlet of the first water pump 5 is connected to the port a of the four-way valve 95, the port b of the four-way valve 95 is connected to the liquid supply port of the energy storage converter coolant channel 8, the port c of the four-way valve 95 is connected to the coolant channel inlet of the plate heat exchanger 2, and the port d of the four-way valve 95 is connected to the outlet of the second heat exchanger 4;

[0056] Among them, port a of the four-way valve 95 is connected to port c of the four-way valve 95, and port b of the four-way valve 95 is connected to port d of the four-way valve 95; or port a of the four-way valve 95 is connected to port b of the four-way valve 95, and port c of the four-way valve 95 is connected to port d of the four-way valve 95.

[0057] By controlling the connectivity of the four-way valve, the operation of different control pipelines can be achieved, which is convenient for temperature control of lithium battery packs and energy storage converters in high and low temperature environments.

[0058] Specific: See Figure 4 and Figure 5 As shown, when the lithium battery pack and energy storage converter are operating in summer or in a very high ambient temperature, port a of four-way valve 95 is connected to port c of four-way valve 95, and port b of four-way valve 95 is connected to port d of four-way valve 95, starting the refrigeration cycle. The temperature control system is divided into two circuits, cooling the lithium battery pack and energy storage converter respectively:

[0059] The high-temperature water / ethylene glycol solution in the battery pack coolant channel 7 passes through the first water pump 5 and enters port C from port A through the four-way valve. It then exchanges heat with the refrigerant in the refrigeration cycle in the plate heat exchanger 2. The low-temperature solution after heat exchange cools the lithium battery pack in the battery pack coolant channel 7 again, and the cycle continues.

[0060] The refrigerant in the refrigeration cycle exchanges heat with the coolant in the battery pack coolant channel 7 in the plate heat exchanger 2, absorbs heat, and evaporates to become a low-temperature, low-pressure gas. After passing through the compressor 1, it becomes a high-temperature, high-pressure gaseous refrigerant, enters the first heat exchanger 3, and is condensed into a high-temperature, high-pressure liquid by the first fan 31. The liquid refrigerant passes through the electronic expansion valve 10 and becomes a low-temperature, low-pressure liquid, which re-enters the plate heat exchanger 2, continuing the cycle.

[0061] Since the operating temperature range of the energy storage converter is higher, a natural cooling source is used to cool the converter, and high-temperature water is returned to the energy storage converter in a continuous cycle.

[0062] Since the operating temperature range of the energy storage inverter is higher, a natural cold source is used to cool the energy storage inverter. The high-temperature return water passes through the second heat exchanger 4, and the temperature is reduced after heat exchange with the external air brought by the second fan 41. It enters the b port from the flow channel d through the four-way valve 95, and is re-cooled and enters the energy storage inverter coolant channel 8 under the action of the second water pump 6. The energy storage inverter coolant channel 8 cools the energy storage inverter thereon and circulates continuously.

[0063] See also Figure 4 and Figure 6 As shown, when the lithium battery pack and energy storage converter are operating in winter or in very low ambient temperatures, and the outside air temperature can meet the operating temperature requirements of both the battery pack and the energy storage converter, port a of four-way valve 95 is connected to port b of four-way valve 95, and port c of four-way valve 95 is connected to port d of four-way valve 95, starting the refrigeration cycle. The temperature control system is combined into a single loop, with the battery pack coolant channel 7 and the energy storage converter coolant channel 8 connected in series to share a common natural cooling system:

[0064] The high-temperature water / ethylene glycol solution flowing out of the energy storage converter coolant channel 8 enters the second heat exchanger 4, exchanges heat with the outside air guided by the second fan 41 for cooling, and enters port c from port d through the four-way valve 95. Since the lithium battery pack is more sensitive to the operating temperature than the energy storage converter, the low-temperature solution first enters the battery pack coolant channel 7 to cool the lithium battery pack on the battery pack coolant channel 7. After heat exchange, it becomes a lower temperature solution, enters the four-way valve 95 through the first water pump 5, and the four-way valve 95 enters port b from port a. Under the action of the second water pump 6, the energy storage converter on the energy storage converter coolant channel 8 is cooled. After heat exchange, it becomes a high-temperature solution and re-enters the second heat exchanger 4 for continuous circulation.

[0065] The two modes of this embodiment are switched by rotating the valve core of the four-way valve to change the fluid flow direction.

[0066] In the description of the present application, the description with reference to the terms "one embodiment", "some embodiments", "in the present embodiment", "specific example", or "some examples" means that the specific features, mechanisms, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, mechanisms, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0067] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A temperature control system for parallel cooling of batteries and energy storage converters, characterized in that: It comprises a compressor (1), a plate heat exchanger (2), a first heat exchanger (3), a second heat exchanger (4), a first water pump (5) and a second water pump (6); The coolant channel outlet of the plate heat exchanger (2) is in communication with the liquid supply port of the battery pack coolant channel (7), and the liquid return port of the battery pack coolant channel (7) is in communication with the coolant channel inlet of the plate heat exchanger (2) via the first water pump (5); the exhaust port of the compressor (1) is in communication with the refrigerant channel inlet of the plate heat exchanger (2) via the first heat exchanger (3), and the refrigerant channel outlet of the plate heat exchanger (2) is in communication with the air inlet of the compressor (1); The outlet of the second heat exchanger (4) is connected to the liquid supply port of the energy storage converter coolant channel (8), and the liquid return port of the energy storage converter coolant channel (8) is connected to the inlet of the second heat exchanger (4) through the second water pump (6).

2. The temperature control system for parallel cooling of batteries and energy storage converters according to claim 1, characterized in that: The outlet of the first water pump (5) is communicated with the inlet of the coolant channel of the plate heat exchanger (2) through a first ball valve (91), and the outlet of the second heat exchanger (4) is communicated with the liquid supply port of the coolant channel (8) of the energy storage converter through a second ball valve (92); The outlet of the coolant channel of the plate heat exchanger (2) is connected to the outlet of the second heat exchanger (4) through a third ball valve (93), and the outlet of the first water pump (5) is connected to the return liquid port of the coolant channel (8) of the energy storage converter through a fourth ball valve (94); The first ball valve (91) and the second ball valve (92) are opened, and the third ball valve (93) and the fourth ball valve (94) are closed; or the first ball valve (91) and the second ball valve (92) are closed, and the third ball valve (93) and the fourth ball valve (94) are opened.

3. The temperature control system for parallel cooling of batteries and energy storage converters according to claim 1, characterized in that: It also includes a four-way valve (95), wherein the four-way valve (95) includes a port a, a port b, a port c and a port d; The outlet of the first water pump (5) is communicated with the port a of the four-way valve (95), the port b of the four-way valve (95) is communicated with the liquid supply port of the coolant channel (8) of the energy storage converter, the port c of the four-way valve (95) is communicated with the coolant channel inlet of the plate heat exchanger (2), and the port d of the four-way valve (95) is communicated with the outlet of the second heat exchanger (4); The port a of the four-way valve (95) is connected to the port c of the four-way valve (95), and the port b of the four-way valve (95) is connected to the port d of the four-way valve (95); or the port a of the four-way valve (95) is connected to the port b of the four-way valve (95), and the port c of the four-way valve (95) is connected to the port d of the four-way valve (95).

4. The temperature control system for parallel cooling of batteries and energy storage converters according to claim 1, characterized in that: The outlet of the first heat exchanger (3) is connected to the refrigerant channel inlet of the plate heat exchanger (2) through an electronic expansion valve (10).

5. The temperature control system for parallel cooling of batteries and energy storage converters according to claim 1, characterized in that: The first heat exchanger (3) is provided with a first fan (31).

6. The temperature control system for parallel cooling of batteries and energy storage converters according to claim 1, characterized in that: The second heat exchanger (4) is provided with a second fan (41).

7. The temperature control system for parallel cooling of batteries and energy storage converters according to claim 1, characterized in that: The coolant in the battery pack coolant channel (7) and the energy storage converter coolant channel (8) is water or ethylene glycol.

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