Charging pile internal temperature detection method, charging detection system and charging pile

Abstract

The invention discloses a charging pile internal temperature detection method, a charging detection system and a charging pile, and relates to the technical field of electric vehicle charging, the method comprises the following steps: obtaining a target data packet, and analyzing the target data packet to obtain a first parameter; acquiring a second parameter; the second parameter comprises the current environment temperature and the current charging power in the charging pile; obtaining a current compensation temperature based on a temperature compensation model, the first parameter and the second parameter; the temperature compensation model is used for indicating the relation among the compensation temperature, the charging power and the environment temperature; obtaining a target voltage, and determining a target temperature of a detection point of the charging pile based on the target voltage; and determining the actual temperature of the detection point according to the current compensation temperature and the target temperature. According to the method, the detection precision is improved through temperature compensation, and charging safety is guaranteed.

Description

Technical Field

[0001] The present application relates to the technical field of electric vehicle charging, and provides a method for detecting the internal temperature of a charging pile, a charging detection system, and a charging pile. Background Art

[0002] Charging piles are devices used to provide charging services for electric vehicles. They transmit electrical energy to the battery of electric vehicles through the power network to help vehicles complete the charging process. Charging piles generate heat during the charging process, especially in the case of high-power charging, long-term charging or equipment abnormalities. This heat accumulation may bring serious safety hazards. Therefore, temperature detection of the main heating parts inside the charging pile is closely related to charging safety protection. It is an important means to ensure charging safety and stable operation, and it is also the key to improving the safety and reliability of electric vehicle charging services.

[0003] The existing method for detecting the internal temperature of a charging pile is mainly to realize temperature detection through a thermistor. However, the thermistor itself has poor reliability and is easily affected by external interference, resulting in low detection accuracy. Summary of the invention

[0004] The main purpose of the present application is to provide a charging pile internal temperature detection method, a charging detection system and a charging pile, aiming to solve the problem of low detection accuracy of the internal temperature of the charging pile.

[0005] In a first aspect, the present application provides a method for detecting the internal temperature of a charging pile, the method comprising:

[0006] Obtain a target data packet, and parse the target data packet to obtain a first parameter;

[0007] Obtaining a second parameter; the second parameter includes the current ambient temperature inside the charging pile and the current charging power;

[0008] Based on a temperature compensation model, the first parameter and the second parameter, a current compensation temperature is obtained; the temperature compensation model is used to indicate a relationship between the compensation temperature, the charging power and the ambient temperature;

[0009] Acquire a target voltage, and determine a target temperature of a detection point of the charging pile based on the target voltage;

[0010] The actual temperature of the detection point is determined according to the current compensation temperature and the target temperature.

[0011] Optionally, the formula of the temperature compensation model is as follows:

[0012] Q = log a (T-Tn)+log b (P / Pn)

[0013] Among them, Q is the current compensation temperature, P is the current charging power, T is the current ambient temperature, Pn is the rated power of the charging pile, Tn is the reference temperature, and a and b are the first parameters.

[0014] Optionally, the acquiring the target data packet and parsing the target data packet to obtain the first parameter includes:

[0015] Obtain a target data packet, and extract a plurality of test data from the target data packet; wherein each test data includes a charging power, an ambient temperature, and a compensation temperature of any detection point;

[0016] An objective function is determined according to the type of the charging pile, and the plurality of test data are fitted using the objective function to obtain the first parameter.

[0017] Optionally, obtaining the target data packet includes:

[0018] Obtaining the compensation temperature corresponding to the target ambient temperature and the target charging power;

[0019] Keeping the target ambient temperature unchanged, by adjusting the target charging power, obtaining the compensation temperature corresponding to the same ambient temperature and different charging powers; keeping the target charging power unchanged, by adjusting the target ambient temperature, obtaining the compensation temperature corresponding to the same charging power and different ambient temperatures;

[0020] The compensation temperature corresponding to each ambient temperature and each charging power is recorded to obtain the target data packet.

[0021] Optionally, obtaining the compensation temperature corresponding to the target ambient temperature and the target charging power includes:

[0022] Under the target ambient temperature and the target charging power, a set of temperature data is obtained every preset time period to obtain N sets of temperature data; wherein each set of temperature data includes the actual temperature and the target temperature of any detection point, and N is a positive integer;

[0023] Calculate the difference between the actual temperature and the target temperature in each set of temperature data to obtain the temperature difference of N sets of temperature data;

[0024] According to the temperature difference of the N groups of temperature data, a compensation temperature corresponding to the target ambient temperature and the target charging power is determined.

[0025] Optionally, determining the compensation temperature corresponding to the target ambient temperature and the target charging power according to the temperature difference of the N groups of temperature data includes:

[0026] From the temperature differences of the N groups of temperature data, delete the temperature differences of the M groups of temperature data that are greater than a preset threshold, obtain the temperature differences of the NM groups of temperature data, and determine the average value of the temperature differences of the NM groups of temperature data as the compensation temperature corresponding to the target ambient temperature and the target charging power; M is a positive integer less than or equal to N.

[0027] Optionally, acquiring the target voltage and determining the target temperature of the detection point based on the target voltage includes:

[0028] Receiving a target voltage sent by a temperature sensor; the temperature sensor is set within a preset range of the detection point;

[0029] According to a pre-stored target relationship table, the temperature corresponding to the target voltage is determined as the target temperature of the detection point; the target relationship table is used to indicate the corresponding relationship between multiple voltages and multiple temperatures.

[0030] Optionally, before determining the temperature corresponding to the target voltage as the target temperature of the detection point according to the pre-stored target relationship table, the method further includes:

[0031] The target relationship table is determined from a plurality of pre-stored relationship tables according to the type of the temperature sensor.

[0032] In a second aspect, the present application further provides a charging detection system, including a host computer and a charging pile, wherein the charging pile includes a detection point and a processor; wherein:

[0033] The host computer is used to obtain a target data packet, parse the target data packet to obtain a first parameter, and send the first parameter to the processor;

[0034] The processor is used to obtain a second parameter; obtain a current compensated temperature based on a temperature compensation model, the first parameter and the second parameter; obtain a target voltage, and determine a target temperature of the detection point based on the target voltage; determine an actual temperature of the detection point according to the current compensated temperature and the target temperature; the second parameter includes a current ambient temperature inside the charging pile and a current charging power; the temperature compensation model is used to indicate the relationship between the compensated temperature, the charging power and the ambient temperature.

[0035] In a third aspect, the present application also provides a charging pile, including:

[0036] Inspection point;

[0037] A temperature sensor is arranged within a preset range of the detection point, and is used to determine the detected temperature as a target temperature of the detection point; convert the target temperature into a target voltage and output it;

[0038] A processor is communicatively connected to the temperature sensor, and is used to obtain a first parameter and a second parameter; obtain a current compensated temperature based on a temperature compensation model, the first parameter and the second parameter; obtain a target voltage, and determine a target temperature of the detection point based on the target voltage; determine an actual temperature of the detection point according to the current compensated temperature and the target temperature; the second parameter includes a current ambient temperature and a current charging power inside the charging pile; the temperature compensation model is used to indicate the relationship between the compensated temperature, the charging power and the ambient temperature.

[0039] Compared with the prior art, the beneficial effects of the embodiments of the present application are:

[0040] Taking into account that the target temperature of the detection point directly measured by the sensor is inaccurate, in an embodiment of the present application, the current compensated temperature is calculated based on the temperature compensation model, the first parameter and the second parameter (i.e., the current ambient temperature inside the charging pile and the current charging power), and then the target temperature of the detection point is compensated. The actual temperature of the detection point is obtained based on the target temperature and the current compensated temperature, which improves the accuracy of the temperature detection inside the charging pile. It can help operation and maintenance personnel to promptly detect temperature abnormalities inside the charging pile, discover potential faults of the charging pile in advance, and perform repairs in a timely manner to ensure that the charging pile can continue to operate stably, thereby ensuring the safety and reliability of the charging pile during the charging process. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related technologies, the drawings required for use in the embodiments or the related technical descriptions are briefly introduced below. Obviously, the drawings described below are only the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0042] Figure 1 A schematic diagram of the structure of a charging detection system provided in an embodiment of the present application;

[0043] Figure 2 A schematic diagram of a flow chart of a method for detecting the internal temperature of a charging pile provided in an embodiment of the present application;

[0044] Figure 3 A schematic diagram of a flow chart of a host computer parsing a first parameter provided in an embodiment of the present application;

[0045] Figure 4 A schematic diagram of the internal structure of a charging pile provided in an embodiment of the present application. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. According to 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.

[0047] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0048] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0050] For the temperature detection inside the charging pile, the conventional method is to use thermistors to achieve temperature detection. The voltage value at both ends of the thermistor is sampled, differentially amplified and transmitted to the AD port of the processor back end for sampling. The actual resistance value at both ends of the thermistor is calculated based on the sampled voltage, and the corresponding temperature can be obtained from the actual resistance value. However, thermistors have low reliability and accuracy, and the signal needs to be filtered. In addition, they are limited by the safety standards for charging piles. Both SMD and plug-in types have considerable limitations. SMD thermistors need to be isolated, and plug-in thermistors are difficult to install and the process is unreliable.

[0051] Another method is to set a thermocouple on the surface of the detection point and realize temperature detection through thermocouple. Compared with the detection method of thermistor, its reliability and accuracy are improved. However, it is limited by the high cost and complex design of thermocouples, and requires analog-to-digital conversion and isolated sampling. In fact, it is difficult to be widely used in the field of charging piles.

[0052] In view of this, an embodiment of the present application provides a method for detecting the internal temperature of a charging pile, which can be applied to a charging detection system. Figure 1 A structural schematic diagram of a charging detection system provided in an embodiment of the present application, the charging detection system may include a host computer and a charging pile, the charging pile may include a detection point, a processor, and a temperature sensor arranged within a preset range of the detection point, the processor is a microcontroller unit (Microcontroller Unit, MCU), the processor is communicatively connected to the temperature sensor, and the host computer and the processor of the charging pile are communicatively connected.

[0053] In the embodiment of the present application, the detection point can be a main heating part such as a relay or input terminal on a printed circuit board (PCB) inside the charging pile. In order to meet the electrical clearance and creepage distance requirements between high and low voltages, the temperature sensor can be set within a preset range of the detection point, which is generally [3mm, 6mm]. There are no other devices between the temperature sensor and the detection point to prevent the linear relationship between the chip surface temperature of the temperature sensor and the temperature of the detection point from being affected.

[0054] It should be noted that Figure 1Taking the example that the charging pile includes one detection point and one temperature sensor, there is actually no limit on the number of detection points and temperature sensors. The charging pile may include multiple detection points and multiple temperature sensors, each temperature sensor corresponds to one detection point, and each temperature sensor is set within the preset range of the corresponding detection point. For example: the charging pile includes two detection points and two temperature sensors, the two detection points are a relay and an input terminal, respectively, one temperature sensor can be set within the preset range of the relay, and the other temperature sensor can be set within the preset range of the input terminal.

[0055] Figure 2 A flow chart of a method for detecting the internal temperature of a charging pile according to an embodiment of the present application. The method for detecting the internal temperature of a charging pile can be performed by Figure 1 The charging detection system shown is executed. Figure 2 As shown, the charging pile internal temperature detection method may include the following steps:

[0056] S210, obtaining a target data packet, and parsing the target data packet to obtain a first parameter;

[0057] S220, obtaining a second parameter;

[0058] S230, obtaining a current compensation temperature based on the temperature compensation model, the first parameter and the second parameter;

[0059] S240, obtaining a target voltage, and determining a target temperature of a detection point of the charging pile based on the target voltage;

[0060] S250: Determine the actual temperature of the detection point according to the current compensation temperature and the target temperature.

[0061] In S210, the host computer may parse the target data packet to obtain the first parameter of the temperature compensation model. The specific parsing steps will be introduced later.

[0062] In S220, the second parameter may include the current ambient temperature inside the charging pile and the current charging power. The current charging power is usually pre-set by the user, so the processor can directly read the current charging power set by the user. The processor can also detect the ambient temperature inside the charging pile in real time to obtain the second parameter.

[0063] In S230, the processor can substitute the first parameter and the second parameter into the temperature compensation model, which is used to indicate the relationship between the compensation temperature, charging power and ambient temperature. The processor can determine the current compensation temperature corresponding to the current ambient temperature and the current charging power based on the obtained first parameter and second parameter.

[0064] In S240, since the temperature sensor is near the detection point, the temperature detected by the temperature sensor can be determined as the target temperature of the detection point. The target temperature is converted into a target voltage and then sent to the processor. After the processor receives the target voltage, it converts the target voltage into the target temperature of the detection point.

[0065] In S250, since the temperature sensor is a certain distance away from the detection point, the target temperature measured by the temperature sensor may deviate from the actual temperature of the detection point. In order to improve the accuracy of temperature detection, the target temperature may be compensated, and the sum of the target temperature plus the current compensated temperature obtained in S230 is determined as the actual temperature of the detection point.

[0066] In an exemplary embodiment, S210 may specifically include the following steps:

[0067] Obtain a target data packet, and extract multiple test data from the target data packet; wherein each test data includes the charging power, the ambient temperature, and the compensation temperature of any detection point;

[0068] The objective function is determined according to the type of the charging pile, and the objective function is used to fit the multiple test data to obtain the first parameter.

[0069] In the specific implementation process, the host computer can first extract multiple test data from the target data packet. The multiple test data can be test data of the same detection point or test data of different detection points. Each test data includes the charging power of any detection point (i.e., the charging power of the charging pile where any detection point is located), the ambient temperature (i.e., the ambient temperature inside the charging pile where any detection point is located) and the compensation temperature. Then the objective function can be determined according to the type of charging pile. The objective function can be, for example, a binary linear function, a binary quadratic function, a binary logarithmic function, etc. If the charging pile is a charging pile with good internal space sealing and uniform heat dissipation, such as a household AC charging pile, the objective function can use a binary linear function. If the charging pile is a charging pile with a complex internal space and air cooling or liquid cooling, such as a DC high-power liquid-cooled charging pile, the objective function can use a binary quadratic function. If the charging pile is a charging pile with a completely sealed interior and extremely poor basic heat dissipation, such as a 30KW or 40KW power module, the objective function can use a binary logarithmic function. Finally, mathematical modeling tools, such as MATLAB, R language, SPSS, etc., are used to fit multiple test data using the objective function to obtain the first parameter of the temperature compensation model.

[0070] If the objective function is a binary logarithmic function, the formula of the temperature compensation model is as follows:

[0071] Q = log a (T-Tn)+log b (P / Pn)

[0072] Among them, Q is the current compensation temperature, P is the current charging power, T is the current ambient temperature, Pn is the rated power of the charging pile, Tn is the reference temperature, which is fixed at 25°C, and a and b are the first parameters, which can be obtained by fitting multiple test data.

[0073] For example, substitute T = 0°C, P = 1 / 2Pn, Q = 1.8°C into Q = log a (T-Tn)+log b (P / Pn), we get equation (1): 1.8 = loga (30-25) + logb (1 / 2). Substituting T = 50 °C, P = Pn, Q = 2.8 °C into Q = log a (T-Tn)+log b (P / Pn), we get equation (2): 2.8 = loga (50-25) + logb (1). Solving equation (1) and equation (2) together, we get a≈3.16, b≈0.178.

[0074] If the objective function is a binary linear function, the formula of the temperature compensation model is as follows:

[0075] Q=a(P / Pn)+b(T / Tn)+c

[0076] Among them, Q is the current compensation temperature, P is the current charging power, T is the current ambient temperature, Pn is the rated power of the charging pile, Tn is the reference temperature, which is fixed at 25°C, a, b and c are the first parameters, which can be obtained by fitting multiple test data.

[0077] For example, substituting T = 0°C, P = 1 / 2Pn, Q = 1.8°C into Q = a(P / Pn) + b(T / Tn) + c, we get equation (3): 1.8 = a / 2 + c. Substituting T = 50°C, P = Pn, Q = 2.8°C into Q = a(P / Pn) + b(T / Tn) + c, we get equation (4): 2.8 = a+2b+c. Substituting T = 25°C, P = 1 / 2Pn, Q = 1.5°C into

[0078] Q = a(P / Pn) + b(T / Tn) + c, and we get equation (5): 1.5 = a / 2 + b + c. Combining equations (3) and (4)

[0079] Solving equation (5), we obtain a = 3.2, b = -0.3, c = 0.2.

[0080] If the objective function is a binary quadratic function, the formula of the temperature compensation model is as follows:

[0081] Q=a(T-Tn)2+b(P / Pn)+c

[0082] Among them, Q is the current compensation temperature, P is the current charging power, T is the current ambient temperature, Pn is the rated power of the charging pile, Tn is the reference temperature, which is fixed at 25°C, a, b and c are the first parameters, which can be obtained by fitting multiple test data.

[0083] For example, substituting T = 0 ° C, P = 1 / 2Pn, Q = 1.8 ° C into Q = a (T-Tn) 2 + b (P / Pn) + c, we get equation (6): 1.8 = a (-25) 2 + b / 2 + c. Substituting T = 50 ° C, P = Pn, Q = 2.8 ° C into Q = a (T-Tn) 2 + b (P / Pn) + c, we get equation (7): 2.8 = a (25) 2 + b + c. Substituting T = 25 ° C, P = 1 / 2Pn, Q = 1.5 ° C into

[0084] Q = a(T-Tn)2+b(P / Pn)+c, we get equation (8): 1.5 = b / 2+c. Combining equations (6) and (7)

[0085] Solving equation (8), we obtain a=0.00048, b=2.0, c=0.5.

[0086] In the embodiment of the present application, taking into account that the internal space airtightness and heat dissipation performance of different types of charging piles are different, by selecting the objective function for a specific type of charging pile for fitting and obtaining the first parameter of the temperature compensation model, it can be ensured that the temperature detection process is more accurate.

[0087] In an exemplary embodiment, the step of acquiring a target data packet includes:

[0088] S211, obtaining a compensation temperature corresponding to a target ambient temperature and a target charging power;

[0089] S212, keeping the target ambient temperature unchanged, and adjusting the target charging power to obtain the compensation temperature corresponding to the same ambient temperature and different charging powers, and keeping the target charging power unchanged, and adjusting the target ambient temperature to obtain the compensation temperature corresponding to the same charging power and different ambient temperatures;

[0090] S213: Record the compensation temperature corresponding to each ambient temperature and each charging power to obtain a target data packet.

[0091] Among them, in S211, the target ambient temperature T1 can be set, for example, T1=25°C, the target charging power can be set to P1=Pn, the target charging pile can be controlled to charge under the conditions of target ambient temperature T1 and target charging power P1, and the compensation temperature Q11 corresponding to T1 and P1 can be recorded.

[0092] In S212, the target ambient temperature T1 can be kept unchanged, and the target charging power can be adjusted to P2, P3, and P4 in sequence, for example: P2 = 1 / 4Pn, P3 = 1 / 2Pn, P4 = 1.2Pn. The compensation temperature Q12 corresponding to T1 and P2, the compensation temperature Q13 corresponding to T1 and P3, and the compensation temperature Q14 corresponding to T1 and P4 are recorded respectively. The target charging power P1 can be kept unchanged, and the target ambient temperature can be adjusted to T2, T3, and T4 in sequence, for example: T2 = -25°C, T3 = 0°C, and T4 = 50°C. The compensation temperature Q21 corresponding to T2 and P1, the compensation temperature Q31 corresponding to T3 and P1, and the compensation temperature Q41 corresponding to T4 and P1 are recorded respectively.

[0093] In S213, a table may be used to record the corresponding relationship among the ambient temperature, the charging power, and the compensation temperature, as shown in Table 1.

[0094] Table 1

[0095] Ambient temperature T(℃) Charging power P(V) Compensation temperature Q(℃) T1＝25℃ P1=Pn Q11 T1＝25℃ P2=1 / 2Pn Q12 T1＝25℃ P3=1 / 4Pn Q13 T1＝25℃ P4=1.2Pn Q14 T2＝-25℃ P1=Pn Q21 T3＝0℃ P1=Pn Q31 T4＝50℃ P1=Pn Q41

[0096] In the embodiment of the present application, taking into account that the ambient temperature and charging power will affect the temperature inside the charging pile, by recording the compensation temperatures corresponding to different ambient temperatures and different charging powers, the corresponding relationship between the ambient temperature, charging power and compensation temperature can be accurately obtained, which helps to establish a more sophisticated temperature compensation model and ensure the accuracy of subsequent temperature compensation.

[0097] In an exemplary embodiment, S211 may specifically include the following steps:

[0098] S2111. Under the target ambient temperature and the target charging power, a set of temperature data is acquired at a preset time interval to obtain N sets of temperature data; wherein each set of temperature data includes the actual temperature and the target temperature of any detection point, and N is a positive integer;

[0099] S2112, calculating the difference between the actual temperature and the target temperature in each set of temperature data to obtain the temperature difference of N sets of temperature data;

[0100] S2113. Determine a compensation temperature corresponding to a target ambient temperature and a target charging power according to a temperature difference of N groups of temperature data.

[0101] In the specific implementation process, a thermocouple can be set at any detection point of the charging pile, and cooperate with an external thermocouple temperature receiving device (including a temperature measurement board and a data acquisition instrument) to record the temperature measured by the thermocouple. Since the measurement accuracy of the thermocouple is high, the temperature measured by the thermocouple can be uploaded to the host computer as the actual temperature of the detection point. In addition, a temperature sensor can be set within the preset range of the detection point. The temperature sensor converts the detected temperature into a voltage signal and sends it to the processor of the charging pile. The processor then converts the voltage signal into the temperature measured by the temperature sensor according to the pre-stored relationship table, and uploads the temperature measured by the temperature sensor as the target temperature of the detection point to the host computer.

[0102] It should be noted that the charging pile for collecting test data and the charging pile for actually detecting temperature can be the same charging pile or different charging piles. Any detection point in the charging pile for collecting test data and the detection point in the charging pile for actually detecting temperature can be the same detection point or different detection points, for example: any detection point in the charging pile for collecting test data is a relay, and the detection point in the charging pile for actually detecting temperature is an input terminal.

[0103] In S2111, the charging pile is controlled to charge under the conditions of the target ambient temperature T1 and the target charging power P1. From the start of charging, the temperature T' measured by the thermocouple (i.e., the actual temperature of the target detection point) and the temperature T" measured by the temperature sensor (i.e., the target temperature of the target detection point) are recorded once every preset time (e.g., 5 minutes) until the temperatures measured by the thermocouple and the temperature sensor are substantially constant, thereby obtaining N sets of temperature data.

[0104] In S2112, for each set of temperature data, the difference between the temperature T' measured by the thermocouple (i.e., the actual temperature of the target detection point) and the temperature T" measured by the temperature sensor (i.e., the target temperature of the target detection point) can be calculated to obtain the temperature difference of each set of temperature data.

[0105] In S2113, the upper computer can directly determine the average value of the temperature difference of N groups of temperature data as the compensation temperature corresponding to the target ambient temperature and target charging power, and can also eliminate M groups of temperature data according to preset conditions, and determine the average value of the temperature difference of the remaining NM groups of temperature data as the compensation temperature corresponding to the target ambient temperature and target charging power, where M is a positive integer less than or equal to N.

[0106] In an exemplary embodiment, the step of S2113 includes:

[0107] From the temperature differences of N groups of temperature data, delete the temperature differences of M groups of temperature data that are greater than a preset threshold, obtain the temperature differences of NM groups of temperature data, and determine the average value of the temperature differences of NM groups of temperature data as the compensation temperature corresponding to the target ambient temperature and target charging power; M is a positive integer less than or equal to N.

[0108] During the specific implementation process, all temperature differences are compared with the preset threshold. If the temperature difference of a group of temperature data is less than or equal to the preset threshold, the temperature difference of this group of temperature data is retained. If the temperature difference of a group of temperature data is greater than the preset threshold, the temperature difference of this group of temperature data is deleted, and the average value of the retained temperature difference is determined as the compensation temperature corresponding to the target ambient temperature and target charging power.

[0109] In the embodiment of the present application, considering that temperature diffusion has a certain delay time, the deviation of the first few groups of temperature data is relatively large. Therefore, eliminating the first few groups of data with large temperature differences can ensure the accuracy of the calculated compensation temperature.

[0110] Please refer to Figure 3 , is a schematic diagram of a flow chart of a host computer parsing a first parameter provided in an embodiment of the present application, and the specific steps are as follows:

[0111] S301. At a target ambient temperature of 25° C. and a target charging power Pn, record the temperature T' measured by the thermocouple and the temperature T" measured by the temperature sensor every five minutes until the temperature is substantially constant.

[0112] S302, calculating the difference between the temperature T' measured by the thermocouple and the temperature T" measured by the temperature sensor, deleting the data with large deviation, and taking the average value of the remaining differences as the compensation temperature Q11.

[0113] S303, maintaining the target ambient temperature at 25°C, changing the target charging power to 1 / 4Pn, and referring to S301 and S302 to obtain the compensation temperature Q12 under this working condition.

[0114] Specifically, at the target ambient temperature of 25°C and the target charging power of 1 / 4Pn, record the temperature T' measured by the thermocouple and the temperature T" measured by the temperature sensor every five minutes until the temperature is basically constant, calculate the difference between T' and T", delete the data with large deviations, and take the average of the remaining differences as the compensation temperature Q12.

[0115] S304, maintaining the target ambient temperature at 25°C, changing the target charging power to 1 / 2Pn, and referring to S301 and S302 to obtain the compensation temperature Q13 under this working condition.

[0116] Specifically, at the target ambient temperature of 25°C and the target charging power of 1 / 2Pn, record the temperature T' measured by the thermocouple and the temperature T" measured by the temperature sensor every five minutes until the temperature is basically constant, calculate the difference between T' and T", delete the data with large deviations, and take the average of the remaining differences as the compensation temperature Q13.

[0117] S305. Keep the target ambient temperature at 25°C unchanged, change the target charging power to 1.2Pn, and refer to S301 and S302 to obtain the compensation temperature Q14 under this working condition.

[0118] Specifically, under the target ambient temperature of 25°C and the target charging power of 1.2Pn, record the temperature T' measured by the thermocouple and the temperature T" measured by the temperature sensor every five minutes until the temperature is basically constant, calculate the difference between T' and T", delete the data with large deviations, and take the average of the remaining differences as the compensation temperature Q14.

[0119] S306. Keep the target charging power Pn unchanged, change the target ambient temperature to -25°C, and refer to S301 and S302 to obtain the compensation temperature Q21 under this working condition.

[0120] Specifically, under the target ambient temperature of -25°C and the target charging power Pn, the temperature T' measured by the thermocouple and the temperature T" measured by the temperature sensor are recorded every five minutes until the temperature is basically constant. The difference between T' and T" is calculated, the data with large deviations are deleted, and the average value of the remaining differences is taken as the compensation temperature Q21.

[0121] S307, keep the target charging power Pn unchanged, change the target ambient temperature to 0°C, and refer to S301 and S302 to obtain the compensation temperature Q31 under this working condition.

[0122] Specifically, under the target ambient temperature of 0°C and the target charging power Pn, record the temperature T' measured by the thermocouple and the temperature T" measured by the temperature sensor every five minutes until the temperature is basically constant, calculate the difference between T' and T", delete the data with large deviations, and take the average of the remaining differences as the compensation temperature Q31.

[0123] S308. Keep the target charging power Pn unchanged, change the target ambient temperature to 50°C, and refer to S301 and S302 to obtain the compensation temperature Q41 under this working condition.

[0124] Specifically, under the target ambient temperature of 50°C and the target charging power Pn, the temperature T' measured by the thermocouple and the temperature T" measured by the temperature sensor are recorded every five minutes until the temperature is basically constant, the difference between T' and T" is calculated, the data with large deviations are deleted, and the average value of the remaining differences is taken as the compensation temperature Q41.

[0125] S309: Record all ambient temperatures, charging powers, and corresponding compensation temperatures in a table.

[0126] The specific table is shown in Table 1 discussed above.

[0127] S310, using the MATLAB function model to fit the data in the table to obtain a first parameter.

[0128] Specifically, the ambient temperature T, charging power P and corresponding compensation temperature Q in the table can be substituted into the objective function (for example, Q = a(P / Pn) + b(T / Tn) + c), and multiple sets of data can be fitted to obtain the first parameter of the temperature compensation model (i.e., the values ​​of a, b and c).

[0129] In an exemplary embodiment, the step of S240 includes:

[0130] S241, receiving a target voltage sent by a temperature sensor; the temperature sensor is set within a preset range of a detection point;

[0131] S242. According to a pre-stored target relationship table, determine the temperature corresponding to the target voltage as the target temperature of the detection point; the target relationship table is used to indicate the corresponding relationship between multiple voltages and multiple temperatures.

[0132] In the specific implementation process, when the temperature of the detection point changes during the charging process of the charging pile, it will be evenly transmitted to the chip surface of the temperature sensor through the PCB. The temperature sensor can convert the detected temperature into a target voltage and send the target voltage to the processor. The processor pre-stores a target relationship table. After receiving the target voltage sent by the temperature sensor, it can search the pre-stored target relationship table for the voltage value closest to the target voltage and determine the temperature corresponding to the voltage value.

[0133] For example, the target relationship table is shown in Table 2:

[0134] Table 2

[0135] Voltage (V) Temperature(℃) 0.5 20 1.0 25 1.5 30 2.0 35 2.5 40

[0136] During the search process, if the target voltage happens to match a voltage value in the relationship table, the temperature corresponding to the matching voltage value is directly determined as the target temperature. For example, if the target voltage is 1.0V, the target temperature is 25°C.

[0137] If the target voltage is between the two voltage values ​​V1 and V2, the corresponding temperature may be estimated by an interpolation method (eg, linear interpolation), and the estimated temperature may be determined as the target temperature.

[0138] The linear interpolation formula is as follows:

[0139]

[0140] Among them, T target is the target temperature, V target is the target voltage, V1 and V2 are two voltage values in the relational table, V1 < V target < V2, T1 is the temperature corresponding to V1 in the relational table, and T2 is the temperature corresponding to V2 in the relational table.

[0141] For example: if the target voltage is 1.25V, then the target temperature is:

[0142]

[0143] In the embodiment of the present application, after receiving the target voltage, the processor can directly obtain the corresponding temperature value only by querying the pre-stored relational table, without performing complex real-time mathematical operations, thereby reducing the computing burden of the processor and making the temperature conversion process more concise and efficient.

[0144] In an exemplary embodiment, before executing S242, the method may further include:

[0145] Determine the target relational table from multiple pre-stored relational tables according to the type of the temperature sensor.

[0146] In the specific implementation process, the charging pile may include multiple detection points and multiple temperature sensors. The types of multiple temperature sensors may be different, and the relational tables corresponding to different types of temperature sensors are different. Therefore, the processor pre-stores multiple relational tables corresponding to multiple types of temperature sensors, and can determine the target relational table from multiple relational tables according to the type of the temperature sensor.

[0147] In the embodiment of the present application, considering that different types of temperature sensors have different response characteristics and output formats, by selecting the appropriate relational table according to the sensor type, the corresponding relationship between the temperature value and the voltage can be ensured to be accurate, and then the voltage value can be accurately converted into the temperature value, eliminating the differences and errors between different types of temperature sensors, and ensuring that the target temperature value of each detection point is more accurate.

[0148] To summarize, the embodiment of the present application provides a method for detecting the internal temperature of a charging pile, analyzes multiple test data of the charging pile (including the ambient temperature, charging power and compensation temperature of any detection point), determines the first parameter of the temperature compensation model, and determines the current compensation temperature of the detection point according to the temperature compensation model, the first parameter and the second parameter (including the current ambient temperature and the current charging power of the detection point), and then compensates for the target temperature detected by the temperature sensor to obtain the actual temperature of the detection point, thereby improving the accuracy of the internal temperature detection of the charging pile and ensuring the safety and reliability of the charging pile during the charging process.

[0149] Based on the above embodiments, the present application also provides a charging detection system. Figure 1 The charging detection system includes a host computer and a charging pile, and the charging pile includes a detection point and a processor; wherein:

[0150] The host computer is used to obtain a target data packet, parse the target data packet to obtain a first parameter, and send the first parameter to the processor;

[0151] The processor is used to obtain the second parameter; based on the temperature compensation model, the first parameter and the second parameter, the current compensated temperature is obtained; the target voltage is obtained, and the target temperature of the detection point is determined based on the target voltage; according to the current compensated temperature and the target temperature, the actual temperature of the detection point is determined; the second parameter includes the current ambient temperature inside the charging pile and the current charging power; the temperature compensation model is used to indicate the relationship between the compensated temperature, the charging power and the ambient temperature.

[0152] In an exemplary embodiment, the temperature compensation model is formulated as follows:

[0153] Q = log a (T-Tn)+log b (P / Pn)

[0154] Among them, Q is the current compensation temperature, P is the current charging power, T is the current ambient temperature, Pn is the rated power of the charging pile, Tn is the reference temperature, and a and b are the first parameters.

[0155] In an exemplary embodiment, the host computer is specifically used to: obtain a target data packet, extract multiple test data from the target data packet; wherein each test data includes the charging power, ambient temperature and compensation temperature of any detection point; determine the objective function according to the type of charging pile, and use the objective function to fit the multiple test data to obtain the first parameter.

[0156] In an exemplary embodiment, the host computer is specifically used to: obtain the compensation temperature corresponding to the target ambient temperature and the target charging power; keep the target ambient temperature unchanged, and obtain the compensation temperature corresponding to the same ambient temperature and different charging powers by adjusting the target charging power, and keep the target charging power unchanged, and obtain the compensation temperature corresponding to the same charging power and different ambient temperatures by adjusting the target ambient temperature; record the compensation temperature corresponding to each ambient temperature and each charging power to obtain the target data packet.

[0157] In an exemplary embodiment, the host computer is specifically used to: obtain a set of temperature data at preset time intervals under a target ambient temperature and a target charging power to obtain N sets of temperature data; wherein each set of temperature data includes the actual temperature and the target temperature of any detection point, and N is a positive integer; calculate the difference between the actual temperature and the target temperature in each set of temperature data to obtain the temperature difference of the N sets of temperature data; and determine the compensation temperature corresponding to the target ambient temperature and the target charging power based on the temperature difference of the N sets of temperature data.

[0158] In an exemplary embodiment, the upper computer is specifically used to: delete the temperature difference of the M group of temperature data greater than a preset threshold from the temperature difference of the N groups of temperature data, obtain the temperature difference of the NM group of temperature data, and determine the average value of the temperature difference of the NM group of temperature data as the compensation temperature corresponding to the target ambient temperature and the target charging power; M is a positive integer less than or equal to N.

[0159] In an exemplary embodiment, the processor is specifically used to: receive a target voltage sent by a temperature sensor; the temperature sensor is set within a preset range of a detection point; according to a pre-stored target relationship table, the temperature corresponding to the target voltage is determined as the target temperature of the detection point; the target relationship table is used to indicate the correspondence between multiple voltages and multiple temperatures.

[0160] In an exemplary embodiment, the processor is further configured to: determine a target relationship table from a plurality of pre-stored relationship tables according to a type of the temperature sensor before determining the temperature corresponding to the target voltage as the target temperature of the detection point according to the pre-stored target relationship table.

[0161] It should be noted that the specific process of the host computer and the processor executing the charging pile internal temperature detection method can be found in the introduction of the above method embodiment, which will not be repeated here.

[0162] In the charging detection system provided in the embodiment of the present application, the host computer can obtain multiple test data of the charging pile (including the ambient temperature, charging power and compensation temperature of any detection point) for fitting, determine the first parameter of the temperature compensation model, and send it to the processor of the charging pile. The processor can determine the current compensation temperature of the detection point based on the temperature compensation model, the first parameter and the second parameter (including the current ambient temperature and current charging power of the detection point), and then compensate the target temperature detected by the temperature sensor, and obtain the actual temperature of the detection point based on the target temperature and the current compensation temperature, thereby improving the accuracy of the internal temperature detection of the charging pile and ensuring the safety and reliability of the charging pile during the charging process.

[0163] On the basis of the above embodiments, the present application also provides a charging pile. Figure 4 The schematic diagram of the internal structure of the charging pile provided in the embodiment of the present application is as follows: Figure 4 As shown, the charging pile may include a detection point, a temperature sensor and a processor.

[0164] The temperature sensor is arranged within a preset range of the detection point, and is used to determine the detected temperature as the target temperature of the detection point; convert the target temperature into a target voltage and output it;

[0165] The processor is communicatively connected with the temperature sensor for obtaining a first parameter and a second parameter; obtaining a current compensated temperature based on a temperature compensation model, the first parameter and the second parameter; obtaining a target voltage, and determining a target temperature of a detection point based on the target voltage; determining an actual temperature of the detection point according to the current compensated temperature and the target temperature; the second parameter includes a current ambient temperature inside the charging pile and a current charging power; the temperature compensation model is used to indicate the relationship between the compensated temperature, the charging power and the ambient temperature.

[0166] In an exemplary embodiment, the processor is specifically used to: receive a target voltage sent by a temperature sensor; the temperature sensor is set within a preset range of a detection point; according to a pre-stored target relationship table, the temperature corresponding to the target voltage is determined as the target temperature of the detection point; the target relationship table is used to indicate the correspondence between multiple voltages and multiple temperatures.

[0167] In an exemplary embodiment, the processor is further configured to: determine a target relationship table from a plurality of pre-stored relationship tables according to a type of the temperature sensor before determining the temperature corresponding to the target voltage as the target temperature of the detection point according to the pre-stored target relationship table.

[0168] It should be noted that the specific process of the processor executing the charging pile internal temperature detection method can be found in the introduction of the above method embodiment, which will not be repeated here.

[0169] The charging pile provided in the embodiment of the present application obtains the temperature of the detection point inside the charging pile through a temperature sensor. The temperature sensor has the characteristics of strong anti-interference, simple circuit and low cost. Compared with the detection method of thermistor in the prior art, the temperature sensor has higher reliability and more accurate temperature detection. Compared with the detection method of thermocouple in the prior art, the cost of the temperature sensor is lower, and there is no need to consider analog-to-digital conversion and isolated sampling, and its design scheme is simpler. And the temperature detected by the temperature sensor is compensated by the temperature compensation model, which improves the accuracy of the internal temperature detection of the charging pile and ensures the safety and reliability of the charging pile during the charging process.

[0170] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0171] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0172] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course, by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as a read-only memory / random access memory, a magnetic disk, or an optical disk), and includes a number of instructions for a multimedia terminal device to execute the methods of each embodiment of the present application.

[0173] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for detecting the internal temperature of a charging pile, characterized in that: The method comprises: Obtain a target data packet, and parse the target data packet to obtain a first parameter; Obtaining a second parameter; the second parameter includes the current ambient temperature inside the charging pile and the current charging power; Based on a temperature compensation model, the first parameter and the second parameter, a current compensation temperature is obtained; the temperature compensation model is used to indicate a relationship between the compensation temperature, the charging power and the ambient temperature; Acquire a target voltage, and determine a target temperature of a detection point of the charging pile based on the target voltage; The actual temperature of the detection point is determined according to the current compensation temperature and the target temperature.

2. The method for detecting the internal temperature of a charging pile according to claim 1, characterized in that: The formula of the temperature compensation model is as follows: Q=log a (T-Tn)+log b (P / Pn) Among them, Q is the current compensation temperature, P is the current charging power, T is the current ambient temperature, Pn is the rated power of the charging pile, Tn is the reference temperature, and a and b are the first parameters.

3. The method for detecting the internal temperature of a charging pile according to claim 1, characterized in that: The step of obtaining a target data packet and parsing the target data packet to obtain a first parameter includes: Obtain a target data packet, and extract a plurality of test data from the target data packet; wherein each test data includes a charging power, an ambient temperature, and a compensation temperature of any detection point; An objective function is determined according to the type of the charging pile, and the plurality of test data are fitted using the objective function to obtain the first parameter.

4. The method for detecting the internal temperature of a charging pile according to claim 3, characterized in that: The step of obtaining the target data packet comprises: Obtaining the compensation temperature corresponding to the target ambient temperature and the target charging power; Keeping the target ambient temperature unchanged, by adjusting the target charging power, obtaining the compensation temperature corresponding to the same ambient temperature and different charging powers; keeping the target charging power unchanged, by adjusting the target ambient temperature, obtaining the compensation temperature corresponding to the same charging power and different ambient temperatures; The compensation temperature corresponding to each ambient temperature and each charging power is recorded to obtain the target data packet.

5. The method for detecting the internal temperature of a charging pile according to claim 4, characterized in that: The obtaining of the compensation temperature corresponding to the target ambient temperature and the target charging power includes: Under the target ambient temperature and the target charging power, a set of temperature data is obtained every preset time period to obtain N sets of temperature data; wherein each set of temperature data includes the actual temperature and the target temperature of any detection point, and N is a positive integer; Calculate the difference between the actual temperature and the target temperature in each set of temperature data to obtain the temperature difference of N sets of temperature data; According to the temperature difference of the N groups of temperature data, a compensation temperature corresponding to the target ambient temperature and the target charging power is determined.

6. The method for detecting the internal temperature of a charging pile according to claim 5, characterized in that: The determining, according to the temperature difference of the N groups of temperature data, a compensation temperature corresponding to the target ambient temperature and the target charging power includes: From the temperature differences of the N groups of temperature data, delete the temperature differences of the M groups of temperature data that are greater than a preset threshold, obtain the temperature differences of the NM groups of temperature data, and determine the average value of the temperature differences of the NM groups of temperature data as the compensation temperature corresponding to the target ambient temperature and the target charging power; M is a positive integer less than or equal to N.

7. The method for detecting the internal temperature of a charging pile according to claim 1, characterized in that: The acquiring the target voltage and determining the target temperature of the detection point based on the target voltage includes: Receiving a target voltage sent by a temperature sensor; the temperature sensor is set within a preset range of the detection point; According to a pre-stored target relationship table, the temperature corresponding to the target voltage is determined as the target temperature of the detection point; the target relationship table is used to indicate the corresponding relationship between multiple voltages and multiple temperatures.

8. The method for detecting the internal temperature of a charging pile according to claim 7, characterized in that: Before determining the temperature corresponding to the target voltage as the target temperature of the detection point according to the pre-stored target relationship table, the method further includes: The target relationship table is determined from a plurality of pre-stored relationship tables according to the type of the temperature sensor.

9. A charging detection system, characterized in that: It includes a host computer and a charging pile, and the charging pile includes a detection point and a processor; wherein: The host computer is used to obtain a target data packet, parse the target data packet to obtain a first parameter, and send the first parameter to the processor; The processor is used to obtain a second parameter; obtain a current compensated temperature based on a temperature compensation model, the first parameter and the second parameter; obtain a target voltage, and determine a target temperature of the detection point based on the target voltage; determine an actual temperature of the detection point according to the current compensated temperature and the target temperature; the second parameter includes a current ambient temperature inside the charging pile and a current charging power; the temperature compensation model is used to indicate the relationship between the compensated temperature, the charging power and the ambient temperature.

10. A charging pile, characterized in that: include: Inspection point; a temperature sensor, arranged within a preset range of the detection point, for determining the detected temperature as a target temperature of the detection point; Convert the target temperature into a target voltage and output it; A processor, connected to the temperature sensor for obtaining a first parameter and a second parameter; Based on the temperature compensation model, the first parameter and the second parameter, obtaining a current compensation temperature; Obtain a target voltage, and determine a target temperature of the detection point based on the target voltage; determine an actual temperature of the detection point according to the current compensation temperature and the target temperature; the second parameter includes the current ambient temperature inside the charging pile and the current charging power; the temperature compensation model is used to indicate the relationship between the compensation temperature, the charging power and the ambient temperature.

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