A method for controlling air cooling zones of electric energy storage

Abstract

The present invention discloses an air cooling zoning control method for electric energy storage, comprising: building an air cooling air duct, wherein the air cooling air duct comprises an air cooling system arranged above a battery pack, a fan corresponding to each battery pack located in the air inlet direction of the air cooling system, and a fan corresponding to each battery pack located in the air outlet direction, wherein the fan speed is set in 1 to n gears from low speed to high speed; obtaining the highest temperature k in the battery pack max and the minimum temperature k min ; k max and k min Compared with the suitable operating temperature of lithium batteries, when the minimum temperature k min When the temperature is lower than the first preset temperature, the air conditioner is started and set to the second preset temperature for heating. max When the temperature is higher than the third preset temperature, the air conditioner is started and set to the second preset temperature for cooling; the range kc of the battery pack temperature is obtained, and the fan gear corresponding to each battery pack is controlled according to the range kc; the advantage of the present invention is that the battery cell temperature of the battery pack for power storage is accurately controlled.

Description

Technical Field

[0001] The present invention relates to the technical field of electric energy storage control, and in particular to an air-cooling zoning control method for electric energy storage. Background Art

[0002] Power-level energy storage is an indispensable core element in the new power system. Thanks to the development of power batteries, electrochemical energy storage with lithium iron phosphate as the mainstream has become the main body of the current new energy storage. Lithium iron phosphate electrochemical energy storage adopts the PACK package integration method and is assembled in a container. Because it is in a limited space, a large amount of heat will be generated during operation. The temperature control system is a key to power energy storage. At present, air cooling with air conditioning is mostly used. The advantages are simple structure, mature technology and low cost. However, the circulation form is single. Generally, the air inlet of the air conditioner is placed on the top of the battery stack, and the air circulation in the battery cell is completed by the PACK package fan. This method often has the problem of large temperature difference and poor heat dissipation / heating effect of the battery cell far away from the air outlet.

[0003] Chinese patent publication number CN104638317A discloses a heat dissipation control method for a vehicle-mounted power battery cooling fan, the method comprising: obtaining the current vehicle speed, vehicle operating conditions and battery maximum temperature; determining whether the current battery maximum temperature is greater than or equal to the preset fan opening temperature; if the current battery maximum temperature is greater than or equal to the fan opening temperature, then determining the current maximum allowable gear of the cooling fan based on the current vehicle operating conditions and the preset noise requirements at the current vehicle speed, and selecting a gear that meets the current heat dissipation requirements and does not exceed the current maximum allowable gear to control the operation of the cooling fan. According to the heat dissipation control method for the vehicle-mounted power battery cooling fan, the contribution of the power battery cooling fan to the vehicle noise is reasonably reduced to the greatest extent, while meeting the power battery temperature balancing requirements, so that the temperature of each part of the power battery is kept consistent. However, it is mainly adjusted for the passenger compartment temperature, and it performs heat dissipation control by fan gear control, which also has the problem of large temperature difference, poor heat dissipation / heating effect of the battery cell far away from the fan, and cannot accurately control the battery cell temperature of the battery pack for power storage. Summary of the invention

[0004] The technical problem to be solved by the present invention is how to accurately control the temperature of the battery cells of a battery pack for electric energy storage.

[0005] The present invention solves the above technical problems by the following technical means: an air cooling partition control method for electric energy storage, comprising the following steps:

[0006] Step a: Building an air cooling duct, the air cooling duct comprising an air cooling system disposed above the battery pack, a fan corresponding to each battery pack located in the air inlet direction of the air cooling system, and a fan corresponding to each battery pack located in the air outlet direction, the fan speed being set in 1 to n gears from low speed to high speed;

[0007] Step b: Get the maximum temperature k in the battery pack max and the minimum temperature k min ;

[0008] Step c: Set k max and k min Compared with the suitable operating temperature of lithium batteries, when the minimum temperature k min When the temperature is lower than the first preset temperature, the air conditioner is started and set to the second preset temperature for heating. max When the temperature is higher than the third preset temperature, the air conditioner is started and set to the second preset temperature for cooling;

[0009] Step d: Obtain the temperature range kc of the battery pack, and control the fan gear position corresponding to each battery pack according to the temperature range kc.

[0010] Furthermore, the step b further comprises:

[0011] The maximum operating temperature should be lower than the first fire alarm value k bjg , the highest temperature currently obtained k max Greater than the first fire alarm value k bjg When the value is removed, the second highest temperature is assigned as the highest temperature k max , and so on; the lowest operating temperature should be higher than the second fire alarm value k bjd , when the minimum temperature k min Lower than the second fire alarm value k bjd When the value is removed, the second lowest operating temperature is assigned as the lowest temperature k min , and so on; among them, the second fire alarm value k bjd Less than the first fire alarm value k bjg .

[0012] Furthermore, the suitable operating temperature of the lithium battery is 20-35°C.

[0013] Furthermore, the first preset temperature ranges from 8 to 12°C, and the second preset temperature ranges from 24 to 28°C.

[0014] Furthermore, the first preset temperature is 10°C and the second preset temperature is 26°C.

[0015] Furthermore, the third preset temperature ranges from 38 to 42°C.

[0016] Furthermore, the third preset temperature is 40°C.

[0017] Furthermore, the calculation method for obtaining the extreme difference kc of the temperature of the battery cell in the battery pack is kc=k max -k min .

[0018] Furthermore, the fan gear control corresponding to each battery pack according to the range difference kc includes:

[0019] Each temperature level is kc / n. If kc / n is greater than 2°C, then the formula Si=[(k i -k min +0.1)*n / kc]-1Get the fan gear position S of the ith battery pack i , where k i is the operating temperature of the battery pack.

[0020] Furthermore, the fan gear control corresponding to each battery pack according to the range difference kc also includes:

[0021] If kc / n is less than 2°C, calculate kc / (n-1), kc / (n-2) until kc / (nx) is greater than 2°C. i -k min +0.1)*(nx) / kc]-1Get the fan gear position S of the ith battery pack i , where x is a gear position less than n.

[0022] The advantages of the present invention are as follows: the present invention proposes an air cooling partition control method for power energy storage, firstly, k max and k min The air conditioning temperature and mode are set by comparing with the suitable operating temperature of the lithium battery. First, the temperature is roughly controlled quickly. Then, the fan gear corresponding to each battery pack is controlled according to the extreme difference kc of the battery pack temperature. The air circulation mode is changed by adjusting the speed of the battery pack inlet fan to improve the overall temperature control accuracy, thereby accurately controlling the battery cell temperature of the power storage battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of an air cooling duct in an air cooling partition control method for electric energy storage disclosed in an embodiment of the present invention;

[0024] Figure 2 The present invention is a flowchart of an air-cooling zone control method for electric energy storage disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] like Figure 1 and Figure 2 As shown, a method for controlling air cooling zones of electric energy storage includes the following steps:

[0027] Step 1: Continue reading Figure 1 , build an air cooling duct, the air cooling duct includes an air cooling system arranged above the battery pack 2, a fan 1 corresponding to each battery pack 2 located in the air inlet direction of the air cooling system, and a fan 1 corresponding to each battery pack 2 located in the air outlet direction, and the speed of the fan 1 is set from 1 to n gears from low speed to high speed, that is, the speed of the fan 1 in gear 1 is the lowest, and the speed of the fan 1 in gear n is the highest; Figure 1 The middle battery pack 2 is formed by stacking a plurality of battery cells 201 . Figure 1 Only one fan is shown at the air inlet and one fan at the air outlet. In actual application, multiple fans can be set at the air inlet and multiple fans can also be set at the air outlet.

[0028] Step 2: Read the operating temperature signal k of each energy storage PACK (battery pack 2) i , take the lowest temperature k in the PACK min and the maximum temperature k max However, the maximum operating temperature should be lower than the first fire alarm value k bjg , when the maximum temperature k max Greater than the first fire alarm value k bjg When the value is removed, the second highest operating temperature is assigned to k max , and so on. However, the minimum operating temperature should be higher than the second fire alarm value k bjd , when the minimum temperature k min Lower than the second fire alarm value k bjd When the value is removed, the second lowest operating temperature is assigned to k min , and so on. That is:

[0029] k max =max(k i ) and (k max <k bjg );

[0030] k min =min(k i ) and (k min >kbjd ).

[0031] Step 3: Set the maximum temperature k max and the minimum temperature k min Compared with the suitable operating temperature of lithium batteries of 20-35℃. min When the temperature is below 10℃, start the air conditioner and set it to heating at 26℃. max When the temperature is above 40℃, start the air conditioner and set it to cool to 26℃.

[0032] Step 4: Control the fan 1 position according to the extreme difference kc of the energy storage PACK operating temperature. The extreme difference kc is the difference between the highest and lowest operating temperatures, that is, kc = k max -k min .

[0033] Step 5: Control the fan 1 gear according to the operating temperature extreme difference kc. Each gear temperature is kc / n. If kc / n is greater than 2°C, the fan 1 gear S of the i-th PACK is i According to its operating temperature k i With the minimum operating temperature k min The difference is divided by the gear temperature and then rounded to determine:

[0034] Si=[(k i -k min +0.1)*n / kc]-1.

[0035] Step 6: When the temperature is suitable and the air duct is reasonable, based on the energy saving requirement, if kc / n is less than 2°C, the maximum speed is reduced to reduce the power consumption of fan 1. That is, kc / (n-1) and kc / (n-2) are calculated until kc / (nx) is greater than 2°C, and x should not be greater than n. At this time, the fan 1 gear S of the i-th PACK i for:

[0036] Si=[(k i -k min +0.1)*(nx) / kc]-1.

[0037] Through the above technical solution, the present invention proposes an air cooling partition control method for power energy storage, firstly, k max and k min The air conditioning temperature and mode are set by comparing with the suitable operating temperature of the lithium battery. First, the rough temperature control is quickly achieved, and then the fan 1 gear corresponding to each battery pack 2 is controlled according to the extreme difference kc of the temperature of the battery pack 2. The air circulation mode is changed by adjusting the speed of the air inlet fan 1 of the battery pack 2 to improve the overall temperature control accuracy, thereby accurately controlling the temperature of the battery cell 201 of the battery pack 2 for power storage.

[0038] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling air cooling zones of electric energy storage, characterized in that: The following steps are involved: Step a: Building an air cooling duct, the air cooling duct comprising an air cooling system disposed above the battery pack, a fan corresponding to each battery pack located in the air inlet direction of the air cooling system, and a fan corresponding to each battery pack located in the air outlet direction, the fan speed being set in 1~n gears from low speed to high speed; Step b: Get the maximum temperature k in the battery pack max and the minimum temperature k min ; The maximum operating temperature should be lower than the first fire alarm value k bjg , the highest temperature currently obtained k max Greater than the first fire alarm value k bjg When the value is removed, the second highest temperature is assigned as the highest temperature k max , and so on; the lowest operating temperature should be higher than the second fire alarm value k bjd , when the minimum temperature k min Lower than the second fire alarm value k bjd When the value is removed, the second lowest operating temperature is assigned as the lowest temperature k min , and so on; among them, the second fire alarm value k bjd Less than the first fire alarm value k bjg ; Step c: Set k max and k min Compared with the suitable operating temperature of lithium batteries, when the minimum temperature k min When the temperature is lower than the first preset temperature, the air conditioner is started and set to the second preset temperature for heating. max When the temperature is higher than the third preset temperature, the air conditioner is started and set to the second preset temperature for cooling; Step d: Obtain the temperature range kc of the battery cells in the battery pack, and control the fan gear corresponding to each battery pack according to the temperature range kc. The calculation method for obtaining the temperature range kc of the battery cells in the battery pack is kc=k max -k min .

2. The air cooling partition control method for electric energy storage according to claim 1 is characterized in that: The suitable operating temperature of the lithium battery is 20-35°C.

3. The air cooling partition control method for electric energy storage according to claim 1 is characterized in that: The first preset temperature ranges from 8 to 12°C, and the second preset temperature ranges from 24 to 28°C.

4. The air cooling partition control method for electric energy storage according to claim 3 is characterized in that: The first preset temperature is 10°C, and the second preset temperature is 26°C.

5. The air cooling partition control method for electric energy storage according to claim 1 is characterized in that: The third preset temperature ranges from 38 to 42°C.

6. The air cooling partition control method for electric energy storage according to claim 5 is characterized in that: The third preset temperature is 40°C.

7. The air cooling partition control method for electric energy storage according to claim 1 is characterized in that: The fan gear position control corresponding to each battery pack according to the range difference kc includes: Each temperature is kc / n. If kc / n is greater than 2°C, then the formula Si=[(k i -k min +0.1)*n / kc]-1Get the fan gear position S of the ith battery pack i , where k i is the operating temperature of the battery pack.

8. The air cooling partition control method for electric energy storage according to claim 7 is characterized in that: The fan gear control corresponding to each battery pack according to the range difference kc also includes: If kc / n is less than 2°C, calculate kc / (n-1), kc / (n-2) until kc / (nx) is greater than 2°C. i -k min +0.1)*(nx) / kc]-1Get the fan gear position S of the ith battery pack i , where x is a gear position less than n.

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