High-power liquid cooling charging system intelligent temperature rise prediction method, high-power liquid cooling charging system intelligent temperature control method and high-power liquid cooling charging system

Abstract

The invention discloses an intelligent temperature rise prediction method of a high-power liquid cooling charging system, an intelligent temperature control method of the high-power liquid cooling charging system and the high-power liquid cooling charging system, and the method comprises the steps: collecting a charging gun port temperature, a charging current, a cooling liquid temperature and a cooling liquid flow rate, and carrying out the calculation to obtain a heat production rate and a heat dissipation rate; the cooling liquid flow rate and / or the charging power are / is adjusted according to the predicted temperature, so that efficient heat dissipation of the port of the charging gun is achieved, energy consumption can be reduced, and the high-temperature duration of the port of the charging gun can be shortened.

Description

Technical Field

[0001] The present invention relates to the field of liquid cooling and heat dissipation technology, and in particular to an intelligent temperature rise prediction method for a high-power liquid cooling charging system, an intelligent temperature control method for a high-power liquid cooling charging system, and a high-power liquid cooling charging system. Background Art

[0002] In the context of the rapid development of the electric vehicle industry, DC fast charging technology is gradually replacing traditional AC slow charging technology due to its advantages of fast charging. Compared with AC slow charging, DC fast charging can significantly shorten the charging time, thereby improving charging efficiency and user experience. For example, it only takes 20 to 90 minutes to fully charge a fully discharged pure electric vehicle through a DC fast charging pile, while an AC charging pile takes 8 to 10 hours. Although the cost and battery loss of DC charging piles are relatively large, their efficient charging capacity has made them widely used in the public charging field. However, this charging mode will cause a large amount of reactive heat to be generated at the port during the charging process. The heat generated is proportional to the charging power. The greater the power, the more obvious the heat loss and the greater the heat loss. According to the law of conservation of energy, heat needs to be released outward. When the vehicle is in a high-power charging condition, the heat of the charging pile and the vehicle interface connection facilities will be transferred to the socket position, which is easy to cause the port to overheat, and even cause a fire in severe cases.

[0003] To this end, the prior art proposes a solution to cool the charging gun port by liquid cooling. Compared with natural heat dissipation or air cooling, liquid cooling has higher heat dissipation efficiency and can quickly cool the charging gun port and maintain it at an appropriate temperature. However, in actual applications, since the flow rate of the coolant in the liquid cooling system is generally adjusted according to the current charging gun port temperature, the charging gun port still has a significant accumulation of thermal effects, resulting in a decrease in liquid cooling heat dissipation efficiency. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned defects or problems existing in the background technology, and to provide an intelligent temperature rise prediction method for a high-power liquid-cooled charging system, an intelligent temperature control method for a high-power liquid-cooled charging system and a high-power liquid-cooled charging system. Through the intelligent temperature rise prediction method, the accumulation of thermal effects at the charging gun port can be reduced and the liquid cooling heat dissipation efficiency can be improved.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] Technical Solution 1: A method for intelligent temperature rise prediction of a high-power liquid-cooled charging system, wherein the high-power liquid-cooled charging system dissipates heat from the charging gun port through flowing coolant, comprising: collecting the current temperature of the charging gun port, the charging current of the charging gun, the temperature before the heat exchange position between the coolant and the charging gun port, and the flow rate of the coolant at the start time of a preset cycle; determining the heat generation rate of the charging gun port and the heat dissipation rate of the coolant according to the current temperature of the charging gun port, the charging current of the charging gun, the temperature before the heat exchange position between the coolant and the charging gun port, and the flow rate of the coolant; determining the predicted temperature of the charging gun port at the predicted time based on the heat generation rate and the heat dissipation rate; the predicted time is after the start time of the cycle.

[0007] Technical solution 2 based on technical solution 1: the distance between the predicted moment and the starting moment of the cycle is a first period, and the length of the first period is less than or equal to the length of the cycle.

[0008] Technical Solution 3 based on Technical Solution 2: The heat generation rate of the charging gun port is obtained according to the heat generation rate formula:

[0009] Q gen =I 2 R; the heat dissipation rate of the coolant is obtained according to the heat dissipation rate formula: The predicted temperature is obtained according to the temperature rise formula: Among them, T p is the predicted temperature of the charger port at the predicted time; T c is the current temperature of the charging gun port; Q rate is the temperature rise rate of the charging gun port, Q rate =Q gen -Q conv ; I is the current charging current of the charging gun; R is the resistance of the charging gun port at the current temperature; k is the thermal conductivity of the coolant; μ is the dynamic viscosity of the coolant; c p is the specific heat capacity of the coolant; ρ is the density of the coolant; v is the flow rate of the coolant; L is the diameter of the pipe through which the coolant flows; A is the convection heat exchange area between the coolant and the charging gun port; T l is the temperature before the convective heat exchange between the coolant and the charging gun port; Δt is the first period; c is the specific heat capacity of the charging gun port; m is the mass of the charging gun port.

[0010] In addition, the present invention also provides technical solution four: an intelligent temperature control method for a high-power liquid-cooled charging system, comprising: determining the predicted temperature of the charging gun port in the cycle according to the intelligent temperature rise prediction method for a high-power liquid-cooled charging system as described in any one of technical solutions one to three; comparing the predicted temperature with a preset temperature control threshold, and when the predicted temperature is greater than the temperature control threshold, increasing the flow rate of the coolant and / or reducing the charging power of the charging gun, so that the predicted temperature of the charging gun port in the cycle is less than or equal to the temperature control threshold.

[0011] Technical solution five based on technical solution four: when increasing the flow rate of the coolant, the required flow rate of the coolant is determined according to the difference between the current temperature of the charging gun port and the temperature control threshold.

[0012] Technical solution six based on technical solution five: after determining the required flow rate of the coolant, if the flow rate is less than or equal to the maximum flow rate of the coolant, the flow rate of the coolant is increased to the flow rate, and the charging power of the charging gun is kept unchanged.

[0013] Technical Solution 7 based on Technical Solution 5: After determining the required flow rate of the coolant, if the flow rate is greater than the maximum flow rate of the coolant, the flow rate of the coolant is increased to the maximum flow rate and the charging power of the charging gun is reduced.

[0014] Technical Solution 8 based on Technical Solution 7: When the required flow rate of the coolant is greater than the maximum flow rate of the coolant, the preset maximum heat dissipation rate is used as the heat dissipation rate of the coolant to calculate the charging power that the charging gun should adopt.

[0015] In addition, the present invention also provides technical solution nine: a high-power liquid-cooled charging system, which includes a charging gun and is suitable for dissipating heat to the charging gun port through flowing coolant, and includes: a first temperature sensor, which is used to collect the current temperature of the charging gun port; a second temperature sensor, which is used to collect the current temperature of the position before the coolant and the charging gun port exchange heat; a current detection module, which is used to collect the current charging current of the charging gun; a rate detection module, which is used to collect the current flow rate of the coolant; a prediction module, which is used to collect the current temperature of the charging gun port, the charging current of the charging gun, the temperature before the coolant and the charging gun port exchange heat, and the cold The flow rate of the coolant; determine the heat generation rate of the charging gun port and the heat dissipation rate of the coolant according to the current temperature of the electric gun port, the charging current of the charging gun, the temperature of the coolant before heat exchange with the charging gun port and the flow rate of the coolant; determine the predicted temperature of the charging gun port at the predicted time based on the heat generation rate and the heat dissipation rate; the predicted time is after the start time of the cycle; a control module, which is used to compare the predicted temperature with a preset temperature control threshold, and when the predicted temperature is greater than the temperature control threshold, increase the flow rate of the coolant and / or reduce the charging power of the charging gun, so that the predicted temperature of the charging gun port in the cycle is less than or equal to the temperature control threshold.

[0016] Technical solution ten based on technical solution nine: the control module is also used to determine the required flow rate of the coolant when increasing the flow rate of the coolant according to the difference between the current temperature of the charging gun port and the temperature control threshold, and after determining the required flow rate of the coolant, based on the comparison result of the flow rate with the maximum flow rate of the coolant, choose to only increase the flow rate of the coolant or simultaneously increase the flow rate of the coolant and reduce the charging power of the charging gun.

[0017] It can be seen from the above description of the present invention that, compared with the prior art, the present invention has the following beneficial effects:

[0018] Technical solution 1 provides an intelligent temperature rise prediction method for a high-power liquid-cooled charging system. The high-power liquid-cooled charging system can dissipate heat from the port of the charging gun through flowing coolant. The charging gun port here refers to the part of the charging gun that is connected to the charging port of the electrical device during charging and is prone to heat. In the intelligent temperature rise prediction method, the current temperature of the charging gun port is first collected at the start time of a preset cycle. Based on the current temperature, according to the heat generation rate of the charging gun port and the heat dissipation rate of the coolant, the predicted temperature of the charging gun port at a preset prediction time is calculated and the corresponding value is obtained. The heat source of the charging gun port is the heat loss when the current passes through the charging gun during the charging process. Therefore, the heat generation rate of the charging gun port can be calculated according to the charging current of the charging gun. The heat dissipation rate of the coolant is related to the convection heat transfer coefficient of the coolant relative to the charging gun port, the convection heat transfer area, the temperature of the coolant before convection heat transfer, the current temperature of the charging gun port and the flow rate of the coolant. Based on the above parameters that can be predetermined or obtained by the sensors or detection modules of the charging system itself, the temperature of the charging gun port at a certain moment in the future can be predicted through the above steps, and the next step of control can be performed based on the predicted result, such as increasing the flow rate of the coolant or reducing the charging current of the charging gun, so that the temperature of the charging gun port is reduced to an appropriate range.

[0019] In the second technical solution, the length of the first period is set to be less than or equal to the length of the cycle, so as to ensure that the temperature of the charging gun port is predicted once in each cycle, and the prediction will not affect the prediction process of the next cycle.

[0020] In technical solution three, the heat generation rate of the charging gun port and the heat dissipation rate of the coolant are calculated by a certain formula, and the predicted temperature can be calculated based on the heat generation rate and the heat dissipation rate through the temperature rise formula.

[0021] Technical solution four provides an intelligent temperature control method for a high-power liquid-cooled charging system. After obtaining the predicted temperature through the above-mentioned intelligent temperature rise prediction method, the control method compares the predicted temperature with the preset temperature control threshold, and controls the flow rate of the coolant, the charging power of the charging gun and other parameters according to the comparison result. Therefore, when the predicted temperature is high, the heat exchange efficiency is improved in advance by increasing the flow rate of the coolant or reducing the charging power of the charging gun, thereby improving the heat accumulation of the charger port in advance. Compared with control based on real-time temperature, this pre-control method has higher efficiency, can reduce energy consumption during the control process, and can reduce the length of time that the charger port is in a high temperature state.

[0022] On the other hand, the intelligent temperature control method actually performs intelligent temperature control in two stages. The first stage is to use the temperature rise prediction method to obtain the predicted temperature after the first period based on the current measured values ​​of each parameter, and use this to quickly determine whether temperature control is needed in advance for early intervention; the second stage is to determine the temperature control target by comparing the difference between the root temperature prediction value and the temperature control threshold, and use the constructed temperature rise prediction method to reversely calculate the specific control amount of the increase in coolant flow rate and the charging power reduction, so as to specifically realize the advance control of temperature. Such a two-stage temperature control scheme not only has a more timely advantage compared to the existing technology of temperature control based on real-time temperature, but also compared to the scheme of complex solution of temperature control parameters such as coolant flow rate or charging power reduction based on the goal of maximizing charging benefits at every moment, it can reduce unnecessary complex calculations, reduce the computing power cost of high-power liquid-cooled charging systems, and is conducive to the actual implementation of intelligent temperature control schemes.

[0023] In Technical Solution 5, the required flow rate of the coolant is determined based on the difference between the current temperature of the charging gun port and the temperature control threshold. By calculating this rate, the heat dissipation rate of the coolant to the charging gun port can be accurately increased, ensuring that the coolant can effectively reduce the temperature of the charging gun port without significantly increasing the liquid cooling power consumption.

[0024] In Technical Solution 6, if the required flow rate of the coolant is less than or equal to the maximum flow rate of the coolant, it means that the temperature of the charging gun port can be reduced to below the temperature control threshold by increasing the coolant flow rate. Therefore, the charging power of the charging gun can be kept unchanged, avoiding affecting the charging efficiency of the electrical equipment.

[0025] In Technical Solution 7, if the required coolant flow rate is greater than the maximum coolant flow rate, it means that the temperature of the charging gun port cannot be lowered below the temperature control threshold by increasing the coolant flow rate. At this time, in order to ensure that the temperature of the charging gun port is not too high, when the coolant flow rate is increased to the maximum flow rate, the charging power of the charging gun needs to be reduced synchronously.

[0026] In Technical Solution 8, since the maximum flow rate of the coolant is known, the maximum heat dissipation rate obtained based on the maximum flow rate is also known. By calculating the heat generation rate of the charging gun port based on the known maximum heat dissipation rate, the charging power that the charging gun should use can be easily calculated, greatly reducing the amount of calculations.

[0027] Technical Solution Nine provides a high-power liquid-cooled charging system, through which the temperature of the charging gun port can be intelligently controlled, the energy consumption during the control process can be reduced, and the length of time the charger port is in a high-temperature state can be reduced.

[0028] In Technical Solution 10, the control scheme of the control module is further subdivided, which can achieve a good balance between maintaining charging efficiency and reducing the temperature of the charging gun port. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 A schematic diagram of a module of a high-power liquid-cooled charging system provided in an embodiment of the present invention.

[0031] Description of main reference numerals:

[0032] First temperature sensor 1; second temperature sensor 2; current detection module 3; rate detection module 4; prediction module 5; control module 6; charging gun 7; liquid cooling component 8. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are preferred embodiments of the present invention and should not be regarded as excluding other embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In the claims, description and the above-mentioned drawings of the present invention, unless otherwise clearly defined, the use of terms such as "first", "second" or "third" etc. are for distinguishing different objects rather than for describing a specific order.

[0035] In the claims, specification and the above-mentioned drawings of the present invention, unless otherwise explicitly defined, directional words, such as the terms "center", "lateral", "longitudinal", "horizontal", "vertical", "top", "bottom", "inside", "outside", "up", "down", "front", "back", "left", "right", "clockwise", "counterclockwise", etc., indicating directions or positional relationships are based on the directions and positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the specific protection scope of the present invention.

[0036] In the claims, specification and the above drawings of the present invention, unless otherwise clearly defined, if the term "fixed connection" or "fixed connection" is used, it should be understood in a broad sense, that is, any connection method without a displacement relationship and relative rotation relationship between the two, that is to say, including non-detachable fixed connection, detachable fixed connection, integrated connection and fixed connection through other devices or elements.

[0037] In the claims, description and drawings of the present invention, if the terms "include", "have" and their variations are used, they are intended to mean "including but not limited to".

[0038] Example 1

[0039] Embodiment 1 of the present invention provides an intelligent temperature rise prediction method for a high-power liquid-cooled charging system, wherein the high-power liquid-cooled charging system dissipates heat from a charging gun port through flowing coolant.

[0040] Before explaining the intelligent temperature rise prediction method, it is necessary to explain the composition of the high-power liquid-cooled charging system.

[0041] The high-power liquid-cooled charging system mainly includes a charging stack, a charging pile and a liquid-cooling component 8. The charging stack includes multiple groups of power conversion devices, which can convert AC power from the mains into DC power and transmit it to the charging pile. A charging gun 7 is provided on the charging pile, and the charging gun 7 can be used to charge electrical equipment such as new energy vehicles. The charging gun 7 has a port for connecting to the charging port of the electrical equipment, which is used to transmit electrical energy to the electrical equipment. Therefore, the charging gun port is made of conductive material, which will generate heat during the charging process. The liquid-cooling component 8 includes a water pump, a liquid-cooling pipe, a heat exchanger, and a coolant. The water pump drives the coolant to circulate in the liquid-cooling pipe. When the coolant flows through the heat exchanger, the heat exchanger will take away the heat of the coolant and reduce the temperature of the coolant. The liquid-cooling component 8 is used to cool the charging gun port. When the coolant with a lower temperature flows through the charging gun port position, it will take away the heat of the charging gun port with a higher temperature. After that, the coolant temperature will rise, and then the temperature will be reduced through the heat exchanger. In this way, the heat of the charging gun port will be continuously taken away. Among them, a cold plate made of copper or other materials with high thermal conductivity can be arranged between the charging gun port and the liquid cooling pipe of the liquid cooling component 8. The cold plate is in direct contact with the charging gun port, and the coolant is also in direct contact with the cold plate. Heat will be transferred from the charging gun port to the cold plate, and then carried away by the coolant in contact with the cold plate. The contact area between the cold plate and the charging gun port can be regarded as the convection heat exchange area between the coolant and the charging gun port; the temperature of the coolant before flowing through the cold plate is the temperature before the convection heat exchange between the coolant and the charging gun port; the thermal conductivity of the coolant when conducting heat through the cold plate and the charging gun port is the thermal conductivity of the coolant.

[0042] In actual applications, when the liquid cooling component 8 is used to dissipate heat from the charging gun port, there may be a situation where the heat dissipation efficiency of the liquid cooling component 8 is lower than the heat generation efficiency of the charging gun port. In this case, heat will accumulate at the charging gun port, causing the heat dissipation efficiency of the liquid cooling component 8 to further decrease. At this time, the heat dissipation efficiency of the liquid cooling component 8 can be improved by increasing the flow rate of the coolant or reducing the charging power of the charging gun 7. However, if the actual temperature of the charging gun port has reached the preset threshold, it means that the temperature of the charging gun port is at a high state at this time, and it is necessary to quickly reduce the temperature of the charging gun port by a higher coolant flow rate or a greater reduction in the charging power of the charging gun 7, which will increase the power consumption of the liquid cooling component 8 and reduce the charging efficiency of the electrical equipment.

[0043] To this end, this embodiment provides an intelligent temperature rise prediction method for a high-power liquid-cooled charging system, which can predict the temperature rise of the charging gun port and serve as input information for the next step of control.

[0044] The intelligent temperature rise prediction method provided in this embodiment includes the following steps:

[0045] S101: At the start time of a preset cycle, the current temperature of the charging gun port, the charging current of the charging gun 7, the temperature of the position before the coolant and the charging gun port exchange heat, and the flow rate of the coolant are collected;

[0046] S102: Determine the heat generation rate of the charging gun port and the heat dissipation rate of the coolant according to the current temperature of the charging gun port, the charging current of the charging gun 7, the temperature of the coolant before the heat exchange between the charging gun port and the coolant flow rate;

[0047] S102: Determine a predicted temperature of the charging gun port at a predicted time based on the heat generation rate and the heat dissipation rate.

[0048] The predicted time is after the start time of the cycle, the distance between the predicted time and the start time of the cycle is a first period, and the length of the first period is less than or equal to the length of the cycle.

[0049] Among them, the heat source of the charging gun port is the heat loss when the current passes through the charging gun 7 during the charging process. Therefore, the heat generation rate of the charging gun port can be obtained according to the charging current of the charging gun 7 and the resistance of the charging gun port; liquid cooling heat dissipation is generally achieved by contacting the charging gun port with components such as cold plates, and then allowing the coolant to flow through the cold plate and take away the heat of the cold plate. Therefore, the heat dissipation rate of the coolant is related to the convection heat transfer coefficient of the coolant relative to the charging gun port, the convection heat transfer area, the temperature of the coolant before convection heat transfer, the current temperature of the charging gun port and the flow rate of the coolant; based on the above-mentioned parameters that can be predetermined or obtained by the sensors or detection modules of the charging system itself, the temperature of the charging gun port at a certain moment in the future can be predicted through the above-mentioned steps, and the next step of control can be performed based on the results of the prediction, such as increasing the flow rate of the coolant or reducing the charging current of the charging gun 7, so that the temperature of the charging gun port is reduced to an appropriate range.

[0050] At the same time, the length of the first period is set to be less than or equal to the length of the cycle, so as to ensure that the temperature of the charging gun port is predicted once in each cycle, and the prediction will not affect the prediction process of the next cycle.

[0051] Among them, the current temperature of the charging gun port can be measured by a temperature sensor, and the temperature sensor should be set at a position directly in contact with the charging gun port. The charging current of the charging gun 7 can be measured by the corresponding detection module in the built-in BMS, which can directly obtain the current charging current of the charging gun 7. The temperature of the position before the coolant exchanges heat with the charging gun port can be measured by a temperature sensor, which should be set in the liquid cooling pipe and in direct contact with the coolant. The flow rate of the coolant can be calculated by the speed of the water pump that drives the coolant to flow, and the speed of the water pump can be measured by the corresponding detection module.

[0052] Furthermore, the predicted temperature can be calculated step by step through the following related formulas. Specifically, the heat generation rate of the charging gun port is obtained according to the heat generation rate formula: Q gen =I 2 R; the heat dissipation rate of the coolant is obtained according to the heat dissipation rate formula: The predicted temperature is obtained according to the temperature rise formula: Among them, T p is the predicted temperature of the charger port at the predicted time; T c is the current temperature of the charging gun port; Q rate is the temperature rise rate of the charging gun port, Q rate =Q gen -Q conv; I is the current charging current of the charging gun; R is the resistance of the charging gun port at the current temperature; k is the thermal conductivity of the coolant; μ is the dynamic viscosity of the coolant; c p is the specific heat capacity of the coolant; ρ is the density of the coolant; v is the flow rate of the coolant; L is the diameter of the pipe through which the coolant flows; A is the convection heat exchange area between the coolant and the charging gun port; T l is the temperature before the convective heat exchange between the coolant and the charging gun port; Δt is the first period; c is the specific heat capacity of the charging gun port; m is the mass of the charging gun port.

[0053] Among them, the current temperature of the charging gun port, the current charging current of the charging gun 7, the flow rate of the coolant, and the temperature before the convective heat exchange between the coolant and the charging gun port can all be obtained by measurement. The resistance of the charging gun port at the current temperature can be set to a preset value, or obtained by looking up a table based on the current temperature of the charging gun port. The convective heat exchange area between the coolant and the charging gun port, the specific heat capacity of the charging gun port, and the mass of the charging gun port can all be set to preset values, and the first period can also be a preset value. It can be understood that the specific heat capacity and mass of the charging gun port are mainly the specific heat capacity and mass of its conductive heating element. Among the relevant parameters used in the above formula, the thermal conductivity, dynamic viscosity, specific heat capacity, density of the coolant, and the diameter of the liquid cooling pipe can all be preset values, and the flow rate of the coolant is the actual value measured.

[0054] The calculation process of the predicted temperature can be referred to as follows: first determine a cycle with a preset length. At the start of each cycle, the current temperature of the charging gun port, the charging current of the charging gun 7, the temperature of the position before the heat exchange between the coolant and the charging gun port, and the flow rate of the coolant are measured through sensors or detection modules; then, first calculate the heat generation rate of the charging gun port, then calculate the heat dissipation rate of the coolant, and finally calculate the predicted temperature value.

[0055] Example 2

[0056] Embodiment 2 of the present invention provides an intelligent temperature control method for a high-power liquid-cooled charging system, and the intelligent temperature control method comprises the following steps:

[0057] S201: Determine the predicted temperature of the charging gun port in the cycle according to the intelligent temperature rise prediction method for the high-power liquid-cooled charging system described in Example 1;

[0058] S202: comparing the predicted temperature with a preset temperature control threshold, and when the predicted temperature is greater than the temperature control threshold, increasing the flow rate of the coolant and / or reducing the charging power of the charging gun, so that the predicted temperature of the charging gun port in the cycle is less than or equal to the temperature control threshold;

[0059] S203: After determining the required flow rate of the coolant, if the flow rate is less than or equal to the maximum flow rate of the coolant, increasing the flow rate of the coolant to the flow rate, and keeping the charging power of the charging gun unchanged;

[0060] S204: After determining the required flow rate of the coolant, if the flow rate is greater than the maximum flow rate of the coolant, the flow rate of the coolant is increased to the maximum flow rate, and the charging power of the charging gun is reduced.

[0061] Wherein, in step S202 and step S203, a control process of increasing the flow rate of the coolant is included. When increasing the flow rate of the coolant, the required flow rate of the coolant is determined according to the difference between the current temperature of the charging gun port and the temperature control threshold. And, after determining the required flow rate of the coolant, if the flow rate is greater than the maximum flow rate of the coolant, the flow rate of the coolant is increased to the maximum flow rate, and the charging power of the charging gun 7 is reduced, so that the predicted temperature of the charging gun port in the cycle is less than the temperature control threshold.

[0062] That is to say, the intelligent temperature control method provided in this embodiment mainly achieves the goal of reducing the temperature of the charging gun port through two control processes. The first is to increase the flow rate of the coolant, thereby increasing the convective heat transfer coefficient of the coolant and improving the heat dissipation efficiency of the coolant to the charging gun port; the second is to reduce the charging power of the charging gun 7, that is, to reduce the charging current of the charging gun 7, thereby reducing the heat generation of the charging gun port and reducing the temperature of the charging gun port. Moreover, through the two control processes, the charging power is reduced only when necessary, maximizing the charging benefit of the high-power liquid-cooled charging system on the safe basis that the temperature does not exceed the temperature control threshold.

[0063] Specifically, when the predicted temperature is greater than the temperature control threshold, it means that under the current conditions, if the heat dissipation efficiency is not improved, the temperature of the charging gun port will exceed the temperature control threshold at the predicted time and be in an unstable high temperature state. At this time, it is necessary to first calculate the required flow rate of the coolant, which is calculated based on the difference between the current temperature of the charging gun port and the temperature control threshold. Specifically, refer to the formula in Example 1 to design a formula related to the required flow rate of the coolant, which is as follows:

[0064]

[0065] Among them, T d is the value of the temperature control threshold, and v is the required flow rate of the coolant. This formula indicates that by setting a value of the flow rate of the coolant, the temperature of the charging gun port is not greater than the temperature control threshold after the first period.

[0066] After determining the required flow rate of the coolant, there are two situations. One situation is that the flow rate is less than or equal to the maximum flow rate of the coolant, which means that the temperature of the charging gun port can be reduced to below the temperature control threshold by increasing the flow rate of the coolant. At this time, the flow rate of the coolant is increased to the calculated flow rate, and the charging power of the charging gun 7 is kept unchanged to avoid affecting the charging efficiency of the electrical equipment. The other situation is that the flow rate is greater than the maximum flow rate of the coolant, which means that the temperature of the charging gun port cannot be reduced to below the temperature control threshold by increasing the flow rate of the coolant. At this time, in order to ensure that the temperature of the charging gun port is not too high, when the flow rate of the coolant is increased to the maximum flow rate, the charging power of the charging gun 7 needs to be reduced synchronously.

[0067] When the required flow rate of the coolant is greater than the maximum flow rate of the coolant, the preset maximum heat dissipation rate is used as the heat dissipation rate of the coolant to calculate the charging power that the charging gun 7 should adopt. Since the maximum flow rate of the coolant is known, the maximum heat dissipation rate obtained according to the maximum flow rate is also known. By calculating the heat generation rate of the charging gun port according to the known maximum heat dissipation rate, the charging power that the charging gun 7 should adopt can be conveniently calculated, which greatly reduces the amount of calculation.

[0068] The intelligent temperature control method for a high-power liquid-cooled charging system provided in this embodiment, after obtaining the predicted temperature through the intelligent temperature rise prediction method of the above-mentioned embodiment 1, compares the predicted temperature with a preset temperature control threshold, and controls parameters such as the flow rate of the coolant and the charging power of the charging gun 7 according to the comparison result. Therefore, when the predicted temperature is high, the heat exchange efficiency is improved by increasing the flow rate of the coolant in advance, thereby improving the heat accumulation of the charger port in advance. Compared with control based on real-time temperature, this pre-control method has higher efficiency, can reduce energy consumption during the control process, and can reduce the length of time that the charger port is in a high temperature state.

[0069] On the other hand, this embodiment actually performs intelligent temperature control in two stages. The first stage is to use the temperature rise prediction method of Example 1 to obtain the predicted temperature after the first period based on the current measured values ​​of each parameter, and use this to quickly determine whether temperature control is needed in advance for early intervention; the second stage is to determine the temperature control target by comparing the difference between the root temperature prediction value and the temperature control threshold, and use the temperature rise prediction method constructed in Example 1 to reversely calculate the specific control amount of the increase in the coolant flow rate and the charging power reduction, so as to specifically realize the advance control of the temperature. Such a two-stage temperature control scheme not only has the advantage of being more timely than the existing temperature control scheme based on real-time temperature, but also reduces unnecessary complex calculations and reduces the computing power cost of high-power liquid-cooled charging systems, compared with the scheme that performs complex solutions to temperature control parameters such as coolant flow rate or charging power reduction based on the goal of maximizing charging benefits at every moment, which is conducive to the actual implementation of the intelligent temperature control scheme.

[0070] Example 3

[0071] Embodiment 3 of the present invention provides a high-power liquid-cooled charging system, which includes a charging gun 7 and is suitable for dissipating heat from the charging gun port through flowing coolant. For further description of the high-power liquid-cooled charging system, reference may be made to the relevant parts of Embodiment 1 of the present invention.

[0072] Reference Figure 1 The high-power liquid-cooled charging system provided in this embodiment also includes a first temperature sensor 1, which is used to collect the current temperature of the charging gun port; a second temperature sensor 2, which is used to collect the current temperature of the position before the coolant and the charging gun port exchange heat; a current detection module 3, which is used to collect the current charging current of the charging gun 7; a rate detection module 4, which is used to collect the current flow rate of the coolant; a prediction module 5, which is used to collect the current temperature of the charging gun port, the charging current of the charging gun 7, the temperature before the heat exchange between the coolant and the charging gun port, and the flow rate of the coolant at the start time of a preset cycle; according to the current charging gun port The heat generation rate of the charging gun port and the heat dissipation rate of the coolant are determined based on the temperature of the charging gun 7, the charging current of the charging gun 7, the temperature of the coolant before heat exchange with the charging gun port, and the flow rate of the coolant; the predicted temperature of the charging gun port at the predicted time is determined based on the heat generation rate and the heat dissipation rate; the predicted time is after the start time of the cycle; a control module 6, which is used to compare the predicted temperature with a preset temperature control threshold, and when the predicted temperature is greater than the temperature control threshold, increase the flow rate of the coolant and / or reduce the charging power of the charging gun 7, so that the predicted temperature of the charging gun port in the cycle is less than or equal to the temperature control threshold.

[0073] Among them, the control module 6 is also used to determine the required flow rate of the coolant when increasing the flow rate of the coolant according to the difference between the current temperature of the charging gun port and the temperature control threshold, and after determining the required flow rate of the coolant, according to the comparison result of the flow rate with the maximum flow rate of the coolant, choose to only increase the flow rate of the coolant or simultaneously increase the flow rate of the coolant and reduce the charging power of the charging gun 7.

[0074] Specifically, the first temperature sensor 1, the second temperature sensor 2, the current detection module 3 and the rate detection module 4 are all connected to the prediction module 5 by signal, and the prediction module 5 is connected to the control module 6 by signal. The control module 6 can control the water pump operation rate of the liquid cooling component 8 and the charging power of the charging gun 7 through signal transmission. Specifically, the first temperature sensor 1 can be a thermocouple type sensor, which can directly contact the charging gun port and transmit the current temperature of the charging gun port to the prediction module 5 in real time. The second temperature sensor 2 can be an inserted liquid temperature sensor, which can be inserted into the liquid cooling pipe and directly contact the coolant, and transmit the temperature of the coolant before heat exchange to the prediction module 5. The current detection module 3 can directly obtain the current charging current of the charging gun 7 through the charging management software system built into the charging system, and transmit it to the prediction module 5. The rate detection module 4 can obtain the speed of the water pump through the control software of the liquid cooling component 8, and calculate the flow rate of the coolant according to the speed, and transmit it to the prediction module 5. The prediction module 5 calculates the predicted temperature based on the collected relevant parameter information and the preset program. The control module 6 determines how to lower the temperature of the charging gun port according to the predicted temperature and the current temperature of the charging gun port. For the specific control method, please refer to Example 2.

[0075] The prediction module 5 and the control module 6 both include a processor, a memory and an input / output device, wherein the memory is used to store relevant programs and acquired parameters, the processor is used to perform calculations, and the input / output device is used to receive and transmit data. According to the above description, those skilled in the art can select appropriate devices based on actual needs to obtain the above-mentioned high-power liquid-cooled charging system.

[0076] This embodiment provides a high-power liquid-cooled charging system, through which the temperature of the charging gun port can be intelligently controlled, the energy consumption during the control process can be reduced, and the time that the charger port is in a high temperature state can be reduced.

[0077] The description of the above specification and embodiments is used to explain the protection scope of the present invention, but does not constitute a limitation on the protection scope of the present invention. Through the enlightenment of the present invention or the above embodiments, ordinary technicians in this field can obtain modifications, equivalent substitutions or other improvements to the embodiments of the present invention or part of the technical features thereof through logical analysis, reasoning or limited experiments, which should be included in the protection scope of the present invention.

Claims

1. An intelligent temperature rise prediction method for a high-power liquid-cooled charging system, wherein the high-power liquid-cooled charging system dissipates heat from a charging gun port through flowing coolant, and is characterized in that: include: At the start time of a preset cycle, the current temperature of the charging gun port, the charging current of the charging gun, the temperature of the coolant before heat exchange with the charging gun port, and the flow rate of the coolant are collected; Determine the heat generation rate of the charging gun port and the heat dissipation rate of the coolant according to the current temperature of the charging gun port, the charging current of the charging gun, the temperature of the position before the coolant and the charging gun port exchange heat, and the flow rate of the coolant; The predicted temperature of the charging gun port at a predicted time is determined based on the heat generation rate and the heat dissipation rate; the predicted time is after the start time of the cycle.

2. The intelligent temperature rise prediction method for a high-power cold charging system according to claim 1, characterized in that: The predicted time is separated from the start time of the cycle by a first period, and the length of the first period is less than or equal to the length of the cycle.

3. A high-power charging system intelligent temperature rise prediction method as claimed in claim 2, characterized in that: The heat generation rate of the charging gun port is obtained according to the heat generation rate formula: Q gen =I 2 R; The heat dissipation rate of the coolant is obtained according to the heat dissipation rate formula: The predicted temperature is obtained according to the temperature rise formula: in, T p is the predicted temperature of the charger port at the predicted time; T c is the current temperature of the charging gun port; Q rate is the temperature rise rate of the charging gun port, Q rate =Q gen -Q conv ; I is the current charging current of the charging gun; R is the resistance of the charging gun port at the current temperature; k is the thermal conductivity of the coolant; μ is the dynamic viscosity of the coolant; c p is the specific heat capacity of the coolant; ρ is the density of the coolant; v is the flow rate of the coolant; L is the diameter of the pipe through which the coolant flows; A is the convection heat exchange area between the coolant and the charging gun port; T l is the temperature before the convective heat exchange between the coolant and the charging gun port; Δt is the first period; c is the specific heat capacity of the charging gun port; m is the mass of the charging gun port.

4. An intelligent temperature control method for a high-power liquid-cooled charging system, characterized in that: include: According to the intelligent temperature rise prediction method for a high-power liquid-cooled charging system according to any one of claims 1 to 3, determining the predicted temperature of the charging gun port in the cycle; Compare the predicted temperature with a preset temperature control threshold. When the predicted temperature is greater than the temperature control threshold, increase the flow rate of the coolant and / or reduce the charging power of the charging gun so that the predicted temperature of the charging gun port in the cycle is less than or equal to the temperature control threshold.

5. The intelligent temperature control method of a high-power liquid-cooled charging system as claimed in claim 4 is characterized in that: When the flow rate of the coolant is increased, the required flow rate of the coolant is determined according to the difference between the current temperature of the charging gun port and the temperature control threshold.

6. The intelligent temperature control method of a high-power liquid-cooled charging system as claimed in claim 5, characterized in that: After determining the required flow rate of the coolant, if the flow rate is less than or equal to the maximum flow rate of the coolant, the flow rate of the coolant is increased to the flow rate, and the charging power of the charging gun is kept unchanged.

7. The intelligent temperature control method of a high-power liquid-cooled charging system as claimed in claim 5, characterized in that: After determining the required flow rate of the coolant, if the flow rate is greater than the maximum flow rate of the coolant, the flow rate of the coolant is increased to the maximum flow rate, and the charging power of the charging gun is reduced.

8. The intelligent temperature control method of a high-power liquid-cooled charging system as claimed in claim 7, characterized in that: When the required flow rate of the coolant is greater than the maximum flow rate of the coolant, the preset maximum heat dissipation rate is used as the heat dissipation rate of the coolant to calculate the charging power that the charging gun should adopt.

9. A high-power liquid-cooled charging system, comprising a charging gun, and adapted to dissipate heat from a charging gun port through flowing coolant, characterized in that: include: A first temperature sensor, which is used to collect the current temperature of the charging gun port; A second temperature sensor, which is used to collect the current temperature of the coolant before heat exchange with the charging gun port; A current detection module, which is used to collect the current charging current of the charging gun; A rate detection module, which is used to collect the current flow rate of the coolant; A prediction module, which is used to collect the current temperature of the charging gun port, the charging current of the charging gun, the temperature of the coolant before heat exchange with the charging gun port, and the flow rate of the coolant at the start time of a preset cycle; determine the heat generation rate of the charging gun port and the heat dissipation rate of the coolant according to the current temperature of the charging gun port, the charging current of the charging gun, the temperature of the coolant before heat exchange with the charging gun port, and the flow rate of the coolant; determine the predicted temperature of the charging gun port at the predicted time based on the heat generation rate and the heat dissipation rate; the predicted time is located after the start time of the cycle; A control module is used to compare the predicted temperature with a preset temperature control threshold, and when the predicted temperature is greater than the temperature control threshold, increase the flow rate of the coolant and / or reduce the charging power of the charging gun, so that the predicted temperature of the charging gun port in the cycle is less than or equal to the temperature control threshold.

10. A high-power liquid-cooled charging system as claimed in claim 9, characterized in that: The control module is also used to determine the required flow rate of the coolant when increasing the flow rate of the coolant based on the difference between the current temperature of the charging gun port and the temperature control threshold, and after determining the required flow rate of the coolant, choose to only increase the flow rate of the coolant or simultaneously increase the flow rate of the coolant and reduce the charging power of the charging gun based on the comparison result between the flow rate and the maximum flow rate of the coolant.

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