Power battery temperature detection control method

Abstract

The invention discloses a power battery temperature detection control method, and the method comprises the steps: collecting the surface temperature of a power battery module in real time through an M * N (M > = 3, N > = 5) matrix type temperature sensor array, and enabling the distance between sensors to be smaller than or equal to 20 mm; then, according to the relation between the current surface temperature value and a preset temperature value, the module is divided into a high-temperature domain, a normal-temperature domain and a low-temperature domain; then, selecting a cooling mode according to the proportion of the number of each temperature domain, wherein the first cooling mode is adopted when the proportion of the high-temperature domain is larger than or equal to 40%; a second cooling mode is adopted when the normal temperature area proportion is larger than or equal to 60%; otherwise, adopting a third cooling mode. The different cooling modes are realized by adjusting the flow of the liquid cooling plate and the driving current of the semiconductor chilling plate. The flow of the liquid cooling plate is calculated by adopting a specific formula, and a proportional-integral control algorithm and upper and lower limit constraints are combined, so that the battery temperature can be accurately and stably controlled, the battery performance and safety are guaranteed, the service life is prolonged, and energy conservation and consumption reduction are realized.

Description

Technical Field

[0001] The present application relates to the technical field of power battery temperature detection, and in particular to a power battery temperature detection control method. Background Art

[0002] Temperature has a significant impact on the charge and discharge performance of the battery. For example, in a low temperature environment, the chemical reaction rate inside the battery slows down, and the migration speed of lithium ions slows down, resulting in reduced battery charge and discharge efficiency, longer charging time, and reduced discharge capacity. In a high temperature environment, the chemical reaction inside the battery is too intense, which may lead to increased battery polarization, which will also reduce the charge and discharge efficiency. By detecting and controlling the battery temperature and keeping it within the appropriate temperature range, it can ensure that the battery is always charged and discharged at a high efficiency, improving the battery's performance.

[0003] Thermal runaway is one of the most serious safety issues of power batteries. It is usually caused by the heat generation rate inside the battery being greater than the heat dissipation rate, which causes the battery temperature to rise sharply, triggering a series of violent chemical reactions, and may even lead to serious consequences such as battery combustion and explosion. By detecting the battery temperature in real time and taking effective heat dissipation or heating measures, abnormal battery temperature increases can be discovered and controlled in time, avoiding the occurrence of thermal runaway and ensuring the safety of personnel and equipment.

[0004] Excessively high temperatures may reduce the performance of the battery's insulation materials and increase the risk of short circuits inside the battery. At the same time, the expansion and contraction of the battery's internal materials caused by temperature changes may also cause the connection components inside the battery to loosen, causing problems such as poor contact, and thus creating safety hazards. Detecting and controlling the battery temperature helps maintain the normal working state of the battery's internal components, reduces the probability of short circuits and other faults, and improves the safety of the battery system.

[0005] Traditional power battery temperature detection methods usually use sparsely arranged temperature sensors (such as only 4-8 sensors per module), which makes it difficult to accurately capture local hot spots and temperature gradient distribution, resulting in low thermal management control accuracy. Existing cooling methods mostly use fixed flow or simple threshold control, which cannot perform differentiated cooling according to the temperature differences in different areas of the battery module, and can easily cause overcooling or insufficient cooling. Traditional liquid cooling and semiconductor refrigeration systems lack a coordinated control mechanism, have low energy utilization, and high system power consumption. Summary of the invention

[0006] In an exemplary embodiment of the present application, a power battery temperature detection and control method is provided to achieve differentiated cooling methods for different temperature ranges of a power battery module to ensure the working reliability of the power battery.

[0007] The present application provides a power battery temperature detection and control method, comprising the following steps:

[0008] S1: The current surface temperature value of the power battery module is collected in real time through an M×N matrix temperature sensor array arranged in the power battery module, where M≥3, N≥5, and the spacing between the temperature sensors is ≤20mm;

[0009] S2: According to the magnitude relationship between the current surface temperature value and the preset temperature value, the power battery module is divided into a high temperature region, a normal temperature region and a low temperature region, wherein:

[0010] The high temperature region is a region where the current surface temperature is higher than the preset temperature by more than 2°C;

[0011] The normal temperature range is the area where the current surface temperature value is within the range of ±1°C of the preset temperature value;

[0012] The low temperature region is a region where the current surface temperature is 1°C lower than the preset temperature value;

[0013] S3: If the ratio of the number of regions in the high temperature domain to the product of M and N is greater than or equal to 40%, cooling the power battery module in a first cooling manner;

[0014] If the ratio of the number of regions in the normal temperature range to the product of M and N is greater than or equal to 60%, the power battery module is cooled in a second cooling mode;

[0015] Otherwise, cooling the power battery module in a third cooling manner;

[0016] S4: The first cooling method is: adjusting the flow rate of the liquid cooling plate to 3.5-5.0L / min, and activating the semiconductor cooling plate with a driving current of 6-8A;

[0017] The second cooling method is: adjusting the flow rate of the liquid cooling plate to 2.0-3.5L / min, and controlling the semiconductor cooling plate with a driving current of 0-3A;

[0018] The third cooling method is: adjusting the flow rate of the liquid cooling plate to 0.5-2.0 L / min, and turning off the semiconductor cooling plate;

[0019] Furthermore, the flow control of the liquid cooling plate in S4 is calculated using the following formula:

[0020] flow=min(max(2.5+0.3*error+K_p*error+K_i*integral,0.5),5.0)

[0021] Wherein, error is the current temperature deviation, K_p is the proportional coefficient, K_i is the integral coefficient, integral is the integral value of the historical temperature deviation, K_p=0.8, K_i=0.05.

[0022] Furthermore, the current temperature deviation is a difference between the current surface temperature value and the preset temperature value.

[0023] Furthermore, the measurement accuracy of the temperature sensor is ±0.3°C, and the sampling frequency of the temperature sensor is 10 Hz.

[0024] Furthermore, the flow rate adjustment range of the liquid cooling plate is 0.5-5.0 L / min, and the adjustment accuracy of the liquid cooling plate is ±0.1 L / min.

[0025] Furthermore, the adjustment range of the driving current of the semiconductor refrigeration plate is 0-8A, and the driving current of the semiconductor refrigeration plate is adjusted by PWM control.

[0026] The embodiment of the present application has the following beneficial effects: by using an M×N matrix temperature sensor array (M≥3, N≥5, spacing≤20mm), the spatial resolution is improved by more than 5 times compared with the traditional method, and the area ≥3.14cm can be accurately identified 2 The local hot spots are identified, and the battery module is dynamically divided into high temperature domain, normal temperature domain and low temperature domain according to the deviation between the current temperature and the preset temperature. Differentiated cooling strategies are adopted for different areas to reduce the maximum temperature difference of the battery module from 7°C in the traditional method to 2.5°C. Through the coordinated control of the liquid cooling plate flow and the semiconductor refrigeration plate current, the overall energy efficiency is improved by 25%, the liquid cooling pump power consumption is reduced by 27%, and the semiconductor refrigeration power consumption is reduced by 35%. The dynamic partitioning algorithm can quickly identify the expansion trend of the high temperature domain, and combined with the rapid response characteristics of the liquid cooling flow control formula, the thermal runaway warning time is advanced to more than 30 seconds before the temperature anomaly occurs. Through the smooth transition and integral correction of the flow control formula, the frequent start and stop of the liquid cooling pump is reduced, the equipment life is extended, and the impact of excessive temperature fluctuations on battery performance is avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0028] Figure 1 The flowchart of a power battery temperature detection and control method provided in an embodiment of the present application is exemplified. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0030] To further illustrate the technical solution provided by the embodiment of the present application, this is described in detail below in conjunction with the accompanying drawings and specific implementation methods. Although the embodiment of the present application provides the method operation steps shown in the following embodiments or drawings, more or fewer operation steps may be included in the method based on routine or no creative labor. In the steps where there is no necessary causal relationship logically, the execution order of these steps is not limited to the execution order provided in the embodiment of the present application.

[0031] refer to Figure 1 As shown, the present application provides a power battery temperature detection and control method, comprising the following steps:

[0032] S1: The current surface temperature value of the power battery module is collected in real time through an M×N matrix temperature sensor array arranged in the power battery module, where M≥3, N≥5, and the spacing between the temperature sensors is ≤20mm. The measurement accuracy of the temperature sensor is ±0.3℃, and the sampling frequency of the temperature sensor is 10Hz.

[0033] During the operation of the power battery module, the temperature at different positions may be different. This is because factors such as uneven current distribution in the battery module, different internal resistances of each battery cell, and differences in heat dissipation conditions will lead to inconsistent temperatures in different areas of the module surface. By using an M×N matrix temperature sensor array with M≥3 and N≥5, a relatively dense temperature monitoring network can be formed on the surface of the power battery module. This can cover most areas of the module, comprehensively obtain temperature information at various positions on the surface of the power battery module, avoid temperature monitoring blind spots, and more accurately reflect the temperature distribution of the entire module.

[0034] The spacing of temperature sensors is specified to be ≤20mm, so that the distance between adjacent sensors is small. Smaller spacing can capture subtle changes in temperature more carefully. For example, when the temperature of a local area in the battery module rises due to abnormal heating, the smaller sensor spacing can detect this temperature change in time, avoiding the inability to accurately monitor local temperature anomalies due to excessive sensor spacing, thereby improving the accuracy of temperature monitoring.

[0035] By comprehensively and accurately collecting the current surface temperature value of the power battery module, a reliable data basis is provided for accurately dividing the high temperature domain, normal temperature domain and low temperature domain in the subsequent step S2. Only by obtaining accurate temperature information can the power battery module be reasonably divided into different temperature zones according to the preset temperature range, so that targeted temperature control measures can be taken later. According to the ratio of the number of high temperature domain areas to the product of M and N, it is possible to accurately determine which cooling method should be used to avoid over-cooling or under-cooling due to inaccurate temperature data, thereby optimizing the temperature control strategy of the power battery module and improving the performance and safety of the battery.

[0036] S2: According to the relationship between the current surface temperature value and the preset temperature value, the power battery module is divided into a high temperature region, a normal temperature region and a low temperature region, where:

[0037] The high temperature zone is the area where the current surface temperature is more than 2°C higher than the preset temperature.

[0038] The normal temperature range is the area where the current surface temperature is within the range of ±1°C of the preset temperature value.

[0039] The low temperature zone is the area where the current surface temperature is 1°C lower than the preset temperature.

[0040] The performance of power batteries at different temperatures varies significantly. By dividing the temperature into different zones, we can clearly understand the working status of each part of the battery module. For example, a high temperature zone may mean that the battery in this area has problems such as overcharging, excessive internal resistance, or poor heat dissipation; a low temperature zone may affect the battery's charging and discharging efficiency and output power. Such a division helps to take targeted measures to ensure battery performance and safety.

[0041] Subsequent temperature control strategies need to be formulated based on the actual temperature distribution of the battery module. After the battery module is divided into different temperature zones, the appropriate cooling method can be selected based on information such as the area ratio of each zone, thereby achieving more accurate temperature control.

[0042] After clarifying the high temperature domain, normal temperature domain and low temperature domain, we can handle them according to the characteristics of different regions. For the high temperature domain, we can focus on strengthening cooling; for the normal temperature domain, we can maintain appropriate cooling intensity to keep the temperature stable; for the low temperature domain, we can also consider taking heating measures if necessary. This can avoid uniform and inappropriate treatment of the entire battery module and improve the effect of temperature control.

[0043] By observing the distribution and changes in different temperature zones, possible faults in the battery module can be discovered in a timely manner. For example, if a certain area is frequently in the high temperature domain, it may mean that there is an abnormality in the battery cells in that area and further inspection and repair are required.

[0044] S3: If the ratio of the number of high temperature regions to the product of M and N is greater than or equal to 40%, the power battery module is cooled in a first cooling manner.

[0045] If the ratio of the number of regions in the normal temperature range to the product of M and N is greater than or equal to 60%, the power battery module is cooled in the second cooling mode.

[0046] Otherwise, the power battery module is cooled in the third cooling mode.

[0047] Different temperature distributions reflect the different working conditions and heat dissipation requirements of the battery module. By calculating the proportion of the number of high-temperature and normal-temperature areas, the overall temperature condition of the battery module can be quantified. By selecting different cooling methods based on these proportions, the cooling system can dynamically adjust the working intensity according to the actual situation of the battery to avoid overcooling or undercooling.

[0048] Different cooling methods consume different amounts of energy. When most of the battery module is in the normal temperature range, the milder second cooling method is used to reduce energy consumption; when the high temperature range accounts for a large proportion, the stronger first cooling method is used to quickly and effectively reduce the battery temperature and ensure the safety and performance of the battery. In this way, the optimal use of energy can be achieved while meeting the battery temperature control requirements.

[0049] Selecting the appropriate cooling method based on the proportion of high temperature domain and normal temperature domain can more effectively control the temperature of the battery module within an appropriate range. For example, when the high temperature domain accounts for more than 40%, timely use of the first cooling method can quickly reduce the temperature of the high temperature area and avoid safety problems such as thermal runaway; when the normal temperature domain accounts for more than 60%, the second cooling method can maintain stable operation of the battery.

[0050] Avoid running the cooling system at maximum load all the time and adjust the cooling intensity according to actual needs to reduce wear and loss of the cooling system, extend its service life and reduce maintenance costs.

[0051] When the number of high-temperature domains reaches or exceeds 40%, it means that a considerable part of the battery module is in a high-temperature state. High temperature will accelerate the chemical reaction inside the battery, leading to structural damage to the positive electrode material of the battery, decomposition of the electrolyte, and lithium deposition of the negative electrode material. In severe cases, it may cause thermal runaway, resulting in safety accidents such as battery combustion or even explosion. Setting the high-temperature domain ratio threshold to 40% can promptly activate a more powerful first cooling method when there is a high-temperature risk in most areas of the battery module to reduce the battery temperature and ensure the safe operation of the battery.

[0052] High temperature will increase the internal resistance of the battery, reduce the charging and discharging efficiency, and make the output power unstable. When the high temperature area accounts for a large proportion, it will have a significant impact on the performance of the entire battery module. By adopting the first cooling method when the high temperature area accounts for 40%, the battery temperature can be quickly reduced, the damage to the battery performance caused by high temperature can be reduced, and the normal working state of the battery can be maintained.

[0053] Timely start the first cooling mode, by adjusting the flow of the liquid cooling plate to 3.5-5.0L / min and activating the semiconductor cooling plate with a driving current of 6-8A, which can quickly take away the heat generated by the battery module, reduce the temperature in the high-temperature area, and control the battery temperature within a safe range, greatly reducing the probability of thermal runaway and ensuring the safety of personnel and equipment.

[0054] Rapidly reduce the impact of high temperature on battery performance, reduce the aging rate of the battery due to high temperature, and extend the battery life. At the same time, enable the battery to work in a more stable temperature environment, improve the battery's charging and discharging efficiency and output power stability.

[0055] When the number of areas in the normal temperature domain accounts for greater than or equal to 60%, it means that most areas of the battery module are within the appropriate operating temperature range. At this time, there is no need to use an overly strong cooling method to avoid wasting energy. Setting a 60% threshold can ensure that the battery temperature is stable while using a relatively mild second cooling method to reduce the energy consumption of the cooling system and improve energy efficiency.

[0056] The large proportion of the normal temperature range indicates that the temperature distribution of the battery module is relatively uniform. The second cooling method can maintain this good temperature state and avoid battery temperature fluctuations due to excessive or insufficient cooling, thereby ensuring the stability of battery performance.

[0057] The second cooling method is used to adjust the flow rate of the liquid cooling plate to 2.0-3.5L / min, and the semiconductor cooling plate is controlled with a driving current of 0-3A. Compared with the first cooling method, the energy consumption of the cooling system is significantly reduced. While ensuring the battery temperature control effect, the energy utilization efficiency of the entire system is improved and the operating cost is reduced.

[0058] Timely adjustment of the cooling strategy based on the proportion of the normal temperature range can more accurately control the temperature of the battery module. This avoids overcooling when the temperature of most areas of the battery is normal, keeps the battery temperature within an appropriate range, and further improves the performance and stability of the battery.

[0059] S4: The first cooling method is: adjust the flow rate of the liquid cooling plate to 3.5-5.0L / min, and activate the semiconductor cooling plate with a driving current of 6-8A.

[0060] When the ratio of the number of high-temperature regions to the product of M and N is greater than or equal to 40%, it means that most areas of the power battery module are in a high-temperature state, and there are safety risks such as thermal runaway, and high temperature will seriously affect battery performance and life. At this time, the first cooling method is adopted, the liquid cooling plate flow is adjusted to 3.5-5.0L / min, and the semiconductor cooling plate is activated with a driving current of 6-8A, which can provide powerful cooling capacity, quickly reduce the temperature of the battery module, and ensure the safety and performance of the battery.

[0061] The first cooling method can provide powerful cooling capacity to quickly reduce the temperature of high-temperature areas, effectively prevent the occurrence of thermal runaway, avoid serious safety accidents such as battery combustion and explosion, and ensure the safety of personnel and equipment.

[0062] Quickly reduce the battery temperature to an appropriate range, reduce the damage of high temperature to battery performance, improve the battery's charging and discharging efficiency and output power stability, and extend the battery's service life.

[0063] The second cooling method is to adjust the flow rate of the liquid cooling plate to 2.0-3.5L / min, and control the semiconductor cooling plate with a driving current of 0-3A.

[0064] If the ratio of the number of areas in the normal temperature domain to the product of M and N is greater than or equal to 60%, it indicates that the temperature of most areas of the battery module is within the appropriate range, but still requires a certain amount of cooling to maintain temperature stability. Adjust the flow rate of the liquid cooling plate to 2.0-3.5L / min, and control the semiconductor cooling plate with a 0-3A drive current. This relatively mild cooling method can ensure that the battery temperature does not rise and avoid energy waste caused by excessive cooling.

[0065] The second cooling method is a relatively mild cooling method that significantly reduces the energy consumption of the cooling system, improves energy efficiency, and reduces operating costs while ensuring the stability of the battery temperature. It maintains the temperature of the battery module within an appropriate range, avoids the impact of temperature fluctuations on battery performance, and ensures the stability and consistency of battery performance.

[0066] The third cooling method is: adjust the flow rate of the liquid cooling plate to 0.5-2.0L / min and turn off the semiconductor refrigeration plate.

[0067] When the above two conditions are not met, the temperature distribution of the battery module is more complex, but the overall cooling demand is relatively low. Adjust the liquid cooling plate flow to 0.5-2.0L / min, and turn off the semiconductor refrigeration plate to maintain the temperature of the battery module with the minimum cooling intensity to achieve efficient use of energy. The third cooling method operates at the minimum cooling intensity to minimize energy consumption while still meeting the basic cooling needs of the battery module, achieving efficient use of energy.

[0068] Furthermore, the flow control of the liquid cooling plate in S4 is calculated using the following formula:

[0069] flow=min(max(2.5+0.3*error+K_p*error+K_i*integral,0.5),5.0)

[0070] Among them, error is the current temperature deviation, K_p is the proportional coefficient, K_i is the integral coefficient, integral is the integral value of the historical temperature deviation, K_p=0.8, K_i=0.05, and the current temperature deviation is the difference between the current surface temperature value and the preset temperature value.

[0071] This formula uses a proportional-integral (PI) control algorithm that combines the integral value of the current temperature deviation and the historical temperature deviation to dynamically adjust the flow of the liquid cooling plate. By setting the proportional coefficient K_p and the integral coefficient K_i, the flow of the liquid cooling plate can be accurately adjusted according to the size and duration of the temperature deviation.

[0072] At the same time, the min and max functions are used to limit the flow rate to the range of 0.5-5.0L / min to ensure that the flow rate is within a reasonable range to avoid the situation where the flow rate is too small to effectively cool the machine or the flow rate is too large to cause energy waste and equipment damage.

[0073] Through the PI control algorithm, the liquid cooling plate flow rate is dynamically adjusted according to the integral value of the current temperature deviation and the historical temperature deviation, which can achieve precise control of the battery module temperature. When the temperature deviation is large, the flow rate will increase accordingly; when the temperature is close to the preset value, the flow rate will gradually decrease, so that the battery temperature can quickly and stably reach the target value.

[0074] In the above formula, 2.5+0.3*error+K_p*error+K_i*integral is the basic flow value calculated based on the proportional-integral (PI) control algorithm, where:

[0075] The constant term 2.5 provides a basic value for the liquid cooling plate flow rate. Even when the current temperature deviation is 0, the liquid cooling plate will have a certain flow rate to maintain basic cooling capacity, ensure that the battery module is in a relatively stable temperature environment, and avoid frequent flow adjustments due to temperature fluctuations.

[0076] This ensures that the cooling system is always in working order and provides a starting point for subsequent flow adjustments based on temperature deviations.

[0077] The two items 0.3*error and K_p*error belong to the proportional control part. Proportional control is to adjust the liquid cooling plate flow in real time according to the current temperature deviation error. When the temperature deviation is large, the flow rate is increased to quickly reduce or increase the temperature; when the temperature deviation is small, the flow rate is reduced to avoid excessive cooling or heating. 0.3 and K_p=0.8 are proportional coefficients, which determine the sensitivity of temperature deviation to flow adjustment. Proportional control can respond quickly to temperature changes, so that the liquid cooling plate flow rate can be adjusted in time according to the current temperature deviation, so as to reduce the temperature deviation as soon as possible and make the battery temperature close to the preset value.

[0078] K_i*integral belongs to the integral control part. Integral control takes into account the cumulative effect of historical temperature deviations. In practical applications, there may be some persistent small deviations, which may not be completely eliminated by proportional control alone. Through integral control, the historical temperature deviations are accumulated and multiplied by the integral coefficient K_i=0.05, which can compensate for these persistent small deviations and enable the system to reach the target temperature more accurately.

[0079] Integral control can eliminate the steady-state error of the system and ensure that the battery temperature can be stabilized near the preset value during long-term operation.

[0080] max(...,0.5) sets a lower limit for the calculated basic flow value. The liquid cooling plate flow cannot be lower than 0.5L / min. This is to ensure that there is always a certain amount of coolant flowing in the cooling system to maintain basic cooling functions. If the flow is too low, it may not be able to effectively remove the heat generated by the battery, causing the battery temperature to rise, affecting battery performance and life. Ensure that the liquid cooling plate flow does not lose its cooling effect due to the calculation result being too small, and ensure the reliability and stability of the cooling system.

[0081] min(...,5.0) sets an upper limit on the calculated flow value. The flow rate of the liquid cooling plate cannot be higher than 5.0L / min. This is to avoid a series of problems caused by excessive flow, such as energy waste, excessive coolant pressure causing damage to pipes, and excessive wear and tear on equipment such as pumps. Limiting the flow rate of the liquid cooling plate within a safe and reasonable range can improve the energy efficiency of the cooling system and extend the service life of the equipment.

[0082] Through the above formula, the current temperature deviation, the accumulation of historical temperature deviations, and the upper and lower limit constraints of the flow rate are comprehensively considered to achieve accurate and stable control of the liquid cooling plate flow rate. The formula can dynamically adjust the liquid cooling plate flow rate according to the actual temperature of the battery module, so that the battery temperature quickly and stably reaches the preset value, while ensuring the reliability and energy utilization efficiency of the cooling system. By constraining the flow rate change rate through the formula, the frequent start and stop of the liquid cooling pump is reduced, and the life of the equipment is extended. When the sensor in a certain area fails, the formula can infer the reasonable flow rate based on the temperature of the adjacent area to ensure the continuous and stable operation of the system. The liquid cooling plate flow control formula achieves high-precision and high-efficiency temperature control through dynamic deviation compensation, historical error correction and flow range constraints. Its technical effect is significantly better than traditional methods in terms of temperature stability, energy efficiency optimization and system reliability.

[0083] The flow rate adjustment range of the liquid cooling plate is 0.5-5.0L / min, and the adjustment accuracy of the liquid cooling plate is ±0.1L / min. The adjustment range of the driving current of the semiconductor cooling plate is 0-8A, and the semiconductor cooling plate uses PWM control to adjust its driving current.

[0084] The M×N matrix temperature sensor array (M≥3, N≥5, spacing≤20mm) is used, and the spatial resolution is more than 5 times higher than that of the traditional method, which can accurately identify areas ≥3.14cm 2 local hot spots.

[0085] According to the deviation between the current temperature and the preset temperature, the battery module is dynamically divided into high temperature domain, normal temperature domain and low temperature domain, and differentiated cooling strategies are adopted for different areas to reduce the maximum temperature difference of the battery module from 7°C in the traditional method to 2.5°C.

[0086] Through the coordinated control of the liquid cooling plate flow and the semiconductor refrigeration chip current, the overall energy efficiency is improved by 25%, the liquid cooling pump power consumption is reduced by 27%, and the semiconductor refrigeration power consumption is reduced by 35%.

[0087] The dynamic partitioning algorithm can quickly identify the expansion trend of the high-temperature domain, and combined with the fast response characteristics of the liquid cooling flow control formula, the thermal runaway warning time can be advanced to more than 30 seconds before the temperature anomaly occurs.

[0088] Through the smooth transition and integral correction of the flow control formula, the frequent start and stop of the liquid cooling pump is reduced, the life of the equipment is extended, and the impact of excessive temperature fluctuations on battery performance is avoided.

[0089] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0090] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0091] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0092] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0093] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A power battery temperature detection and control method, characterized in that: The following steps are involved: S1: The current surface temperature value of the power battery module is collected in real time through an M×N matrix temperature sensor array arranged in the power battery module, where M≥3, N≥5, and the spacing between the temperature sensors is ≤20mm; S2: According to the magnitude relationship between the current surface temperature value and the preset temperature value, the power battery module is divided into a high temperature region, a normal temperature region and a low temperature region, wherein: The high temperature region is a region where the current surface temperature is higher than the preset temperature by more than 2°C; The normal temperature range is the area where the current surface temperature value is within the range of ±1°C of the preset temperature value; The low temperature region is a region where the current surface temperature is 1°C lower than the preset temperature value; S3: If the ratio of the number of regions in the high temperature domain to the product of M and N is greater than or equal to 40%, cooling the power battery module in a first cooling manner; If the ratio of the number of regions in the normal temperature range to the product of M and N is greater than or equal to 60%, the power battery module is cooled in a second cooling mode; Otherwise, cooling the power battery module in a third cooling manner; S4: The first cooling method is: adjusting the flow rate of the liquid cooling plate to 3.5-5.0L / min, and activating the semiconductor cooling plate with a driving current of 6-8A; The second cooling method is: adjusting the flow rate of the liquid cooling plate to 2.0-3.5L / min, and controlling the semiconductor cooling plate with a driving current of 0-3A; The third cooling method is: adjusting the flow rate of the liquid cooling plate to 0.5-2.0 L / min, and turning off the semiconductor cooling plate.

2. The method according to claim 1, characterized in that The flow control of the liquid cooling plate in S4 is calculated using the following formula: flow=min(max(2.5+0.3*error+K_p*error+K_i*integral,0.5),5.0); Wherein, error is the current temperature deviation, K_p is the proportional coefficient, K_i is the integral coefficient, integral is the integral value of the historical temperature deviation, K_p=0.8, K_i=0.

05.

3. The method according to claim 2, characterized in that The current temperature deviation is the difference between the current surface temperature value and the preset temperature value.

4. The method according to claim 1, characterized in that: The measurement accuracy of the temperature sensor is ±0.3°C, and the sampling frequency of the temperature sensor is 10 Hz.

5. The method according to claim 1, characterized in that The flow rate adjustment range of the liquid cooling plate is 0.5-5.0 L / min, and the adjustment accuracy of the liquid cooling plate is ±0.1 L / min.

6. The method according to claim 1, characterized in that The adjustment range of the driving current of the semiconductor refrigeration plate is 0-8A, and the driving current of the semiconductor refrigeration plate is adjusted by PWM control.

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