An intelligent charging and discharging test device and method for electric vehicles

Abstract

The present invention relates to the technical field of electric vehicle testing, and discloses an electric vehicle intelligent charging and discharging test device and method, which are suitable for charging and discharging precise control test, charging and discharging compatibility evaluation test, power battery state evaluation test and DC charging electromagnetic compatibility test items; the device includes: a charging and discharging control unit, a low-voltage power supply unit, a charging and discharging metering unit, a bidirectional AC / DC power conversion unit, an insulation monitoring unit, a switch unit, a charging and discharging connection unit, a message reading unit, a wireless communication unit, a temperature acquisition unit and an industrial control unit are connected, the insulation monitoring unit is connected to the switch unit and the bidirectional AC / DC power conversion unit, the message reading unit is connected to the charging and discharging connection unit and the industrial control unit, and the cloud platform is connected to the wireless communication unit and the industrial control unit. The present invention can actively control whether the insulation monitoring function is turned on, and realize the precise control of the charging and discharging current, thereby improving the accuracy, controllability and reliability of the charging and discharging test.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicle testing, and in particular to an electric vehicle intelligent charging and discharging testing device and method. Background Art

[0002] Existing charging pile technology has gradually integrated more intelligent functions, such as wireless communication, remote monitoring and control, data analysis, etc., so that charging piles can be better integrated into the smart grid system. Among them, EMC testing is an important test to ensure the safety of charging piles. EMC testing technology mainly focuses on the electromagnetic compatibility of products, including: EMI testing: Evaluate the level of electromagnetic interference (EMI) generated by the product to ensure that the product does not interfere with other electronic equipment. EMS testing: Evaluate the product's immunity to electromagnetic interference (EMS) to ensure that the product can work normally in an electromagnetic environment. Special tests: including surge testing, voltage change and flicker testing, etc. These tests are carried out in accordance with international or regional standards, such as VDE 0843.

[0003] In the existing technology, the existing test equipment cannot meet the requirements of future electromagnetic compatibility (EMC) testing, especially the demand for adjustable current, and cannot accurately control the size of the charging and discharging current. In addition, the insulation monitoring function in the existing charging pile equipment is usually kept on, which causes false alarms in specific test environments (such as EMC testing) and affects the test process.

[0004] Therefore, there is an urgent need for an intelligent charging and discharging test device and method for electric vehicles, which can actively control whether the insulation monitoring function is turned on, and realize precise control of the charging and discharging current, so as to improve the accuracy, controllability and reliability of the charging and discharging test. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides an intelligent charging and discharging test device and method for electric vehicles, which can actively control whether the insulation monitoring function is turned on, and realize precise control of the charging and discharging current, thereby improving the accuracy, controllability and reliability of the charging and discharging test.

[0006] The present invention provides an electric vehicle intelligent charging and discharging test device, which is suitable for charging and discharging precise control test, charging and discharging compatibility evaluation test, power battery state evaluation test and DC charging electromagnetic compatibility test items; the device comprises: a charging and discharging control unit, a low-voltage power supply unit, a charging and discharging metering unit, a bidirectional AC / DC power conversion unit, an insulation monitoring unit, a switch unit, a charging and discharging connection unit, a message reading unit, a wireless communication unit, an industrial control unit and a cloud platform;

[0007] The charge and discharge control unit is used to receive instructions from the industrial control unit, or receive instructions from the cloud platform through the wireless communication unit; to upload information to the industrial control unit, or to upload information to the cloud platform through the wireless communication unit; to collect information from other units connected to the charge and discharge control unit and control them;

[0008] A low-voltage power supply unit is connected to the charge and discharge control unit and is used to convert the energy of the AC power supply into low-voltage DC energy required for normal operation of the charge and discharge control unit;

[0009] The charge and discharge metering unit is connected to the charge and discharge control unit and is used to collect AC input and DC output power parameters and upload the information to the charge and discharge control unit to control the output voltage and current;

[0010] A bidirectional AC / DC power conversion unit is connected to the charge and discharge control unit and the low-voltage power supply unit to realize bidirectional AC / DC conversion and realize charging and discharging;

[0011] The insulation monitoring unit is connected to the charge and discharge control unit and the bidirectional AC / DC power conversion unit to realize insulation monitoring during the charge and discharge process. A switch or relay is integrated inside the insulation monitoring unit, which can be turned on or off according to the instruction of the charge and discharge control unit, thereby controlling the insulation monitoring unit to be enabled or disabled;

[0012] A switch unit, connected to the charge and discharge control unit and the insulation monitoring unit, for connecting or disconnecting energy transmission;

[0013] The charge-discharge connection unit is connected to the charge-discharge control unit and the switch unit, and is used to match the charging interface of the electric vehicle to realize the charging and discharging of the electric vehicle; the charge-discharge connection unit has a built-in temperature sensor to monitor the temperature rise of the power terminal;

[0014] The message reading unit is connected to the charge and discharge connection unit and the industrial control unit, and is used to read and analyze the communication messages during the charge and discharge process, and obtain the parameters of the charge and discharge process and the state of the power battery;

[0015] A wireless communication unit connected to the charge and discharge control unit and the cloud platform, and used to realize communication between the charge and discharge control unit and the cloud platform;

[0016] The industrial control unit is connected to the charge and discharge control unit and the cloud platform to realize charging and discharging and display the charging and discharging process information; it is used to collect, record and analyze the charging and discharging communication messages in real time;

[0017] The cloud platform is connected with the wireless communication unit and the industrial control unit, and is used to obtain all information during the charging and discharging process, and to obtain all information obtained by the charging and discharging control unit.

[0018] Furthermore, the industrial control unit includes: a charge and discharge control module, a charge and discharge electromagnetic compatibility test control module, a charge and discharge compatibility diagnosis module, and a power battery status evaluation module;

[0019] A charge and discharge control module, used to receive preset charge and discharge current values, control charging and discharging, and display charge and discharge information;

[0020] The charge and discharge electromagnetic compatibility test control module is used to realize the control of charge and discharge and the size of charge and discharge current, control the enabling or disabling of the insulation monitoring unit, and display the charge and discharge information;

[0021] Charge and discharge compatibility diagnosis module; used to automatically record the communication messages during the charge and discharge process, and give compatibility diagnosis results based on the communication messages;

[0022] The power battery status assessment module is used to automatically record the characterization parameters of the power battery and perform power battery status analysis based on the characterization parameters of the power battery.

[0023] Furthermore, the charge and discharge control module includes:

[0024] The charge and discharge parameter setting submodule is used to set the charge and discharge parameters, including the charge and discharge current value and the charge and discharge cut-off SOC;

[0025] The charge and discharge information display submodule is used to display the parameters during the charge and discharge process, including the charge and discharge voltage, charge and discharge current, battery SOC, and the power terminal temperature in the charge and discharge connection unit.

[0026] Furthermore, the charge and discharge electromagnetic compatibility test control module includes:

[0027] The test parameter setting submodule is used to set the charge and discharge current values ​​according to the test requirements;

[0028] Function control submodule, used to shut down or enable the insulation monitoring unit according to test requirements;

[0029] The charge and discharge information display submodule is used to display the parameters during the charge and discharge process.

[0030] Furthermore, the charge and discharge compatibility diagnosis module includes:

[0031] The charge and discharge data processing submodule is connected to the charge and discharge connection unit via the message reading unit, and is used for real-time collection, recording and analysis of charge and discharge communication messages;

[0032] The compatibility analysis submodule is used to analyze the timing of the charging and discharging communication messages, whether there are problems with the message filling content, and to carry out charging and discharging compatibility analysis;

[0033] The charge and discharge information display submodule is used to display the parameters during the charge and discharge process.

[0034] Furthermore, the power battery status assessment module includes:

[0035] The data processing submodule is connected to the charge and discharge connection unit through the message reading unit, and is used to collect, record and analyze the power battery characterization parameters extracted from the charge and discharge communication message in real time, as well as the charge and discharge ambient temperature collected in real time by the temperature collection unit;

[0036] The status analysis submodule has an embedded power battery status analysis model and algorithm, and performs battery status analysis based on the data collected by the data processing submodule.

[0037] Furthermore, the insulation monitoring unit remains in an on state during normal charging and discharging, and remains in a off state during the DC charging electromagnetic compatibility test.

[0038] Furthermore, the electric vehicle intelligent charging and discharging test device also includes: a temperature acquisition unit; the temperature acquisition unit is connected to the charging and discharging control unit and is used to collect the ambient temperature conditions of charging and discharging in real time.

[0039] The present invention also provides an electric vehicle intelligent charging and discharging test method, which is used to execute any one of the above electric vehicle intelligent charging and discharging test devices, and specifically includes:

[0040] The precise control test of charge and discharge includes the following steps:

[0041] Input a preset charging current value or a preset discharging current value through the charging and discharging control module in the industrial control unit;

[0042] The charge and discharge control module determines the actual current value according to the preset charge current value or the preset discharge current value and the protection strategy; wherein the protection strategy is: according to the preset charge current value or the preset discharge current value, the power battery charge and discharge current demand value, and the power battery 1C charge and discharge current value, the minimum value is selected as the actual current value;

[0043] The charge and discharge control unit sends the actual current value to the bidirectional AC / DC power conversion unit to achieve accurate charge and discharge;

[0044] The charge and discharge compatibility evaluation test includes the following steps:

[0045] Insert the charging and discharging connection unit into the vehicle to be tested to charge or discharge the vehicle to be tested;

[0046] The communication messages during the charging and discharging process are automatically recorded through the charging and discharging compatibility diagnosis module in the industrial control unit;

[0047] The communication messages recorded during the current charging and discharging process are compared with the charging and discharging compatibility database built into the industrial control unit to obtain the compatibility diagnosis result;

[0048] The power battery status assessment test includes the following steps:

[0049] Insert the charging and discharging connection unit into the vehicle to be tested;

[0050] The initial SOC value before charging or discharging starts is recorded by the power battery status evaluation module in the industrial control unit;

[0051] According to the current SOC state of the vehicle under test, the vehicle under test is charged or discharged for a preset time, and the cut-off SOC value after charging or discharging is stopped is recorded;

[0052] Calculate the health status of the power battery;

[0053] The DC charging electromagnetic compatibility test includes the following steps:

[0054] The insulation monitoring unit is controlled to be turned off through the charge and discharge electromagnetic compatibility test control module in the industrial control unit;

[0055] Input a preset charging current value or a preset discharging current value through the charging and discharging electromagnetic compatibility test control module in the industrial control unit;

[0056] The charge and discharge electromagnetic compatibility test control module determines the actual current value according to the preset charge current value or the preset discharge current value and the protection strategy;

[0057] The charge and discharge control unit sends the actual current value to the bidirectional AC / DC power conversion unit to achieve precise charging and discharging and perform DC charging electromagnetic compatibility testing.

[0058] The embodiments of the present invention have the following technical effects:

[0059] The present invention realizes accurate and safe charge and discharge control through the cooperation of the industrial control unit, the charge and discharge control unit and the insulation monitoring unit. By setting a protection strategy for charge and discharge, it ensures that the actual charge and discharge current will not be too large to cause damage to the battery. It realizes automatic recording of communication messages during the charge and discharge process and compares them with the database to evaluate the communication compatibility between the vehicle and the charging pile, and can determine whether the communication process complies with the standard regulations, and check the accuracy and stability of data transmission. The state of the power battery is evaluated by analyzing the relevant parameters in the charge and discharge communication messages, and a simple method for estimating the health state of the power battery is provided. It realizes accurate control of the charge and discharge current, which can meet the requirements of the future EMC standard for adjustable current. In the EMC test, the insulation monitoring function of the charging pile can be turned off to avoid false alarms caused by the filter, and ensure the smooth progress of the test.

[0060] In addition, the cloud platform can realize remote monitoring, data analysis and control of the charging and discharging process, improving management and maintenance efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0062] Figure 1 It is a structural schematic diagram of an electric vehicle intelligent charging and discharging test device provided by an embodiment of the present invention;

[0063] Figure 2 is a schematic diagram of the structure of a charge and discharge control module provided in an embodiment of the present invention;

[0064] Figure 3 It is a structural schematic diagram of a charge and discharge electromagnetic compatibility test control module provided by an embodiment of the present invention;

[0065] Figure 4 is a schematic diagram of the structure of a charge and discharge compatibility diagnostic module provided by an embodiment of the present invention;

[0066] Figure 5 It is a structural schematic diagram of a power battery status assessment module provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0067] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0068] The present invention proposes an intelligent charging and discharging test device for electric vehicles. Figure 1 is a structural diagram of an electric vehicle intelligent charging and discharging test device provided by an embodiment of the present invention, see Figure 1 The device is suitable for charge and discharge precision control test, charge and discharge compatibility evaluation test, power battery status evaluation test and DC charging electromagnetic compatibility test projects; the device includes:

[0069] Charge and discharge control unit, low-voltage power supply unit, charge and discharge metering unit, bidirectional AC / DC power conversion unit, insulation monitoring unit, switch unit, charge and discharge connection unit, message reading unit, wireless communication unit, temperature acquisition unit, industrial control unit and cloud platform.

[0070] Furthermore, a liquid cooling source may be added according to the need for charging and discharging power. At the same time, the charging and discharging connection unit also needs to be configured as a charging and discharging connection unit with liquid cooling.

[0071] The charge and discharge control unit is used to receive instructions from the industrial control unit, or receive instructions from the cloud platform through the wireless communication unit; to upload information to the industrial control unit, or to upload information to the cloud platform through the wireless communication unit; to collect information from other units (except the industrial control unit and the low-voltage power supply unit) connected to the charge and discharge control unit and control them.

[0072] The low-voltage power supply unit is connected to the charge and discharge control unit and is used to convert the energy of the AC power supply into the low-voltage DC energy required for the normal operation of the charge and discharge control unit.

[0073] The charge and discharge metering unit is connected to the charge and discharge control unit, and is used to collect AC input and DC output power parameters, and upload the information to the charge and discharge control unit to control the output voltage and current.

[0074] The AC input includes the voltage and current of three-phase AC power, and the DC output includes the output voltage and current of the charge and discharge connection unit.

[0075] The bidirectional AC / DC power conversion unit is connected to the charge and discharge control unit and the low-voltage power supply unit to realize bidirectional AC / DC conversion and realize charging and discharging.

[0076] The insulation monitoring unit is connected to the charge and discharge control unit and the bidirectional AC / DC power conversion unit to realize insulation monitoring of the charge and discharge process. A switch or relay is integrated inside the insulation monitoring unit, which can be turned on or off according to the instructions of the charge and discharge control unit, thereby controlling the insulation monitoring unit to be enabled or disabled.

[0077] Specifically, a switch or relay is integrated inside the insulation monitoring unit, and the charging and discharging electromagnetic compatibility test control module (charging and discharging EMC test control module) in the industrial control unit transmits instructions to the charging and discharging control unit. The charging and discharging control unit controls the switch or relay integrated inside the insulation monitoring unit to open or close according to the instructions, thereby controlling the insulation monitoring unit to be enabled or disabled.

[0078] Furthermore, the insulation monitoring unit remains on during normal charging and discharging to avoid safety risks, and can remain off during DC charging electromagnetic compatibility testing to avoid interference with the experimental process.

[0079] The switch unit is connected to the charge and discharge control unit and the insulation monitoring unit, and is used to connect or shut down energy transmission.

[0080] The charge and discharge connection unit is connected to the charge and discharge control unit and the switch unit, and is used to match the charging interface of the electric vehicle to realize charging and discharging of the electric vehicle; the charge and discharge connection unit has a built-in temperature sensor for monitoring the temperature rise of the power terminal.

[0081] For example, since different countries have different standards, the charging and discharging interfaces are also different. The charging and discharging connection unit in this embodiment can replace the muzzles of different standards to adapt to cars of different national standards to achieve charging and discharging.

[0082] The message reading unit is connected to the charge and discharge connection unit and the industrial control unit, and is used to read and analyze the communication messages during the charge and discharge process, and obtain the parameters of the charge and discharge process and the status of the power battery.

[0083] Exemplarily, the parameters of the charging and discharging process and the state quantities of the power battery may include the charging voltage measurement value, the charging current measurement value, the maximum power battery temperature, the termination state of charge SOC, the minimum voltage of the power battery cell, the maximum voltage of the power battery cell, etc. as specified in the GB / T 27930 standard.

[0084] Furthermore, for vehicles under test that meet Chinese standards, a CAN box can be selected as the message reading unit, and for vehicles under test that meet European standards, Vector's VH5110 can be selected as the message reading unit.

[0085] The wireless communication unit is connected to the charge and discharge control unit and the cloud platform, and is used to realize the communication between the charge and discharge control unit and the cloud platform.

[0086] The temperature collection unit is connected to the charge and discharge control unit and is used to collect the ambient temperature conditions of the charge and discharge in real time.

[0087] The industrial control unit is connected to the charge and discharge control unit and the cloud platform to realize charging and discharging and display the charging and discharging process information; it is used to collect, record and analyze the charging and discharging communication messages in real time.

[0088] Specifically, the industrial control unit can be connected to the charge and discharge control unit via RS232 (one of the serial communication interface standards) or CAN, etc. The industrial control unit includes: a charge and discharge control module, a charge and discharge electromagnetic compatibility test control module, a charge and discharge compatibility diagnosis module, and a power battery status evaluation module.

[0089] Figure 2 is a schematic diagram of the structure of the charge and discharge control module provided in an embodiment of the present invention, see Figure 2 The charge and discharge control module is used to receive preset charge and discharge current values, control charging and discharging, and display charge and discharge information. The charge and discharge control module includes:

[0090] The charge and discharge parameter setting submodule is used to set the charge and discharge parameters, including the charge and discharge current value, charge and discharge cut-off SOC, etc.

[0091] The charge and discharge information display submodule is used to display the parameters during the charge and discharge process, including the charge and discharge voltage, charge and discharge current, battery SOC, power terminal temperature in the charge and discharge connection unit, etc.

[0092] Figure 3 is a schematic diagram of the structure of the charge and discharge electromagnetic compatibility test control module provided by an embodiment of the present invention, see Figure 3 The charge and discharge electromagnetic compatibility test control module is used to realize the control of charge and discharge and the size of charge and discharge current, as well as to control the enable or disable of the insulation monitoring unit and display the charge and discharge information. The charge and discharge electromagnetic compatibility test control module includes:

[0093] The test parameter setting submodule is used to set the charge and discharge current values ​​according to the test requirements;

[0094] Function control submodule, used to shut down or enable the insulation monitoring unit according to test requirements;

[0095] The charge and discharge information display submodule is used to display the parameters during the charge and discharge process.

[0096] Figure 4 is a schematic diagram of the structure of the charge and discharge compatibility diagnosis module provided by an embodiment of the present invention, see Figure 4 , charge and discharge compatibility diagnosis module; used to automatically record the communication messages during the charge and discharge process, and give compatibility diagnosis results based on the communication messages. The charge and discharge compatibility diagnosis module includes:

[0097] The charge and discharge data processing submodule is connected to the charge and discharge connection unit via the message reading unit, and is used for real-time collection, recording and analysis of charge and discharge communication messages;

[0098] The compatibility analysis submodule is used to analyze whether there are any problems with the timing of the charging and discharging communication messages, the message filling content, etc., and to carry out charging and discharging compatibility analysis;

[0099] The charge and discharge information display submodule is used to display the parameters during the charge and discharge process.

[0100] Figure 5 is a schematic diagram of the structure of the power battery status evaluation module provided by the embodiment of the present invention, see Figure 5The power battery status assessment module is used to automatically record the power battery's characterization parameters and perform power battery status analysis based on the power battery's characterization parameters. The power battery's characterization parameters may include the highest single power battery voltage and its group number, the current state of charge SOC, the highest power battery temperature, etc. The power battery status assessment module includes:

[0101] The data processing submodule is connected to the charge and discharge connection unit through the message reading unit, and is used to collect, record and analyze the power battery characterization parameters extracted from the charge and discharge communication message in real time, as well as the charge and discharge ambient temperature collected in real time by the temperature collection unit;

[0102] The status analysis submodule has an embedded power battery status analysis model and algorithm, and performs battery status analysis based on the data collected by the data processing submodule.

[0103] The cloud platform is connected with the wireless communication unit and the industrial control unit, and is used to obtain all information during the charging and discharging process, and to obtain all information obtained by the charging and discharging control unit.

[0104] Exemplarily, charging and discharging control instructions and charging and discharging EMC test control instructions etc. may also be sent through the wireless communication unit to realize the control of local hardware functions through the cloud.

[0105] The embodiment of the present invention further provides an electric vehicle intelligent charging and discharging test method, which is performed by an electric vehicle intelligent charging and discharging test device described in the above embodiment, and specifically includes:

[0106] The precise control test of charge and discharge includes the following steps:

[0107] a1. Input a preset charging current value or a preset discharging current value through the charge and discharge control module in the industrial control unit.

[0108] a2. The charge and discharge control module determines the actual current value according to the preset charge current value or the preset discharge current value and the protection strategy.

[0109] Among them, the protection strategy is: according to the preset charging current value or the preset discharging current value, the power battery charging and discharging current demand value, and the power battery 1C charging and discharging current value, select the minimum value as the actual current value, that is, the actual current value = min (preset charging current value or preset discharging current value, power battery charging and discharging current demand value, power battery 1C charging and discharging current value). C is used to indicate the battery charging and discharging capacity rate. 1C indicates the current intensity when the battery is fully discharged in one hour. For example, a 18650 battery with a nominal 2200mA·h discharges at a 1C intensity for 1 hour and the discharge current is 2200mA.

[0110] a3. The charge and discharge control unit sends the actual current value to the bidirectional AC / DC power conversion unit to achieve accurate charge and discharge.

[0111] The charge and discharge compatibility evaluation test includes the following steps:

[0112] b1. Insert the charge and discharge connection unit into the vehicle to be tested to charge or discharge the vehicle to be tested.

[0113] b2. Automatically record the communication messages during the charging and discharging process through the charging and discharging compatibility diagnosis module in the industrial control unit.

[0114] b3. Compare the communication messages recorded during this charging and discharging process with the charging and discharging compatibility database built into the industrial control unit to obtain the compatibility diagnosis result.

[0115] Exemplarily, the compatibility diagnosis result includes:

[0116] ① Determine whether the communication process between the vehicle under test and the charging pile complies with the communication protocol specified in the standard, such as whether the handshake, authentication and data exchange processes can be completed correctly.

[0117] ② Check the accuracy and stability of data transmission to ensure the correct exchange of information during charging and discharging.

[0118] The power battery status assessment test includes the following steps:

[0119] c1. Insert the charging and discharging connection unit into the vehicle to be tested.

[0120] Specifically, the vehicle to be tested is driven into the operating area of ​​the intelligent charging and discharging test device, and the charging and discharging connection unit is inserted.

[0121] c2. Record the initial SOC value before charging or discharging through the power battery status assessment module in the industrial control unit.

[0122] c3. Charge or discharge the vehicle to be tested for a preset time according to its current SOC state, and record the cut-off SOC value after charging or discharging stops.

[0123] Exemplarily, the preset time is usually set to be greater than 10 minutes.

[0124] c4. Calculate the health status of the power battery. The calculation formula is as follows:

[0125] ;

[0126] ;

[0127] Among them, SOH represents the health status of the battery, Q 当前Indicates the current SOC value of the battery, Q 初始 represents the initial SOC value of the battery, ΔSOC represents the change in SOC during a charge, that is, the SOC value at the end of charging minus the SOC value at the beginning of charging, C 一次充电充入的电量 It represents the amount of electricity charged during a charging process, t represents the start time of charging and discharging, t0 represents the end time of charging and discharging, and I(t) represents the discharge current at time t.

[0128] The DC charging electromagnetic compatibility test includes the following steps:

[0129] d1. Control the insulation monitoring unit to shut down through the charge and discharge electromagnetic compatibility test control module in the industrial control unit.

[0130] Specifically, during the EMC test, the insulation detection function of the charging pile itself can be turned off by shutting down the insulation monitoring module through the industrial control unit as needed to prevent the filter in the EMC darkroom from causing false alarms in insulation detection, resulting in termination of charging and discharging and inability to carry out subsequent EMC tests.

[0131] d2. Input a preset charging current value or a preset discharging current value through the charging and discharging electromagnetic compatibility test control module in the industrial control unit.

[0132] d3. The charge and discharge electromagnetic compatibility test control module determines the actual current value according to the preset charging current value or the preset discharging current value and the protection strategy.

[0133] d4. The charge and discharge control unit sends the actual current value to the bidirectional AC / DC power conversion unit to achieve accurate charging and discharging and perform DC charging electromagnetic compatibility testing.

[0134] The present invention realizes accurate and safe charge and discharge control through the cooperation of the industrial control unit, the charge and discharge control unit and the insulation monitoring unit. By setting a protection strategy for charge and discharge, it ensures that the actual charge and discharge current will not be too large to cause damage to the battery. It realizes automatic recording of communication messages during the charge and discharge process and compares them with the database to evaluate the communication compatibility between the vehicle and the charging pile, and can determine whether the communication process complies with the standard regulations, and check the accuracy and stability of data transmission. The state of the power battery is evaluated by analyzing the relevant parameters in the charge and discharge communication messages, and a simple method for estimating the health state of the power battery is provided. It realizes accurate control of the charge and discharge current, which can meet the requirements of the future EMC standard for adjustable current. In the EMC test, the insulation monitoring function of the charging pile can be turned off to avoid false alarms caused by the filter, and ensure the smooth progress of the test.

[0135] In addition, the cloud platform can realize remote monitoring, data analysis and control of the charging and discharging process, improving management and maintenance efficiency.

[0136] It should be noted that the terms used in the present invention are only for describing specific embodiments, rather than limiting the scope of the present application. As shown in the present specification, unless the context clearly indicates an exception, the words "one", "a", "a kind of" and / or "the" do not specifically refer to the singular, but may also include the plural. The terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method or device. In the absence of more restrictions, the elements defined by the sentence "include one..." do not exclude the presence of other identical elements in the process, method or device including the elements.

[0137] It should also be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship 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 orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense, for example, it 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 it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0138] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

Claims

1. An intelligent charging and discharging test device for electric vehicles, characterized in that: Applicable to charge and discharge precision control test, charge and discharge compatibility assessment test, power battery status assessment test and DC charging electromagnetic compatibility test projects; the device includes: charge and discharge control unit, low voltage power supply unit, charge and discharge metering unit, bidirectional AC / DC power conversion unit, insulation monitoring unit, switch unit, charge and discharge connection unit, message reading unit, wireless communication unit, industrial control unit and cloud platform; The charge and discharge control unit is used to receive instructions from the industrial control unit, or receive instructions from the cloud platform through the wireless communication unit; to upload information to the industrial control unit, or to upload information to the cloud platform through the wireless communication unit; to collect information from other units connected to the charge and discharge control unit and control them; The low-voltage power supply unit is connected to the charge and discharge control unit and is used to convert the energy of the AC power supply into the low-voltage DC energy required for the normal operation of the charge and discharge control unit; The charge and discharge metering unit is connected to the charge and discharge control unit and is used to collect AC input and DC output power parameters and upload the information to the charge and discharge control unit to control the output voltage and current; The bidirectional AC / DC power conversion unit is connected to the charge and discharge control unit and the low-voltage power supply unit, and is used to realize bidirectional AC / DC conversion and realize charging and discharging; The insulation monitoring unit is connected to the charge and discharge control unit and the bidirectional AC / DC power conversion unit, and is used to realize insulation monitoring of the charge and discharge process. A switch or relay is integrated inside the insulation monitoring unit, which can be turned on or off according to the instruction of the charge and discharge control unit, thereby controlling the insulation monitoring unit to be enabled or disabled; The switch unit is connected to the charge and discharge control unit and the insulation monitoring unit, and is used to connect or shut down energy transmission; The charging and discharging connection unit is connected to the charging and discharging control unit and the switch unit, and is used to match the charging interface of the electric vehicle to realize charging and discharging of the electric vehicle; the charging and discharging connection unit has a built-in temperature sensor for monitoring the temperature rise of the power terminal; The message reading unit is connected to the charge and discharge connection unit and the industrial control unit, and is used to read and analyze the communication messages during the charge and discharge process, and obtain the parameters of the charge and discharge process and the state quantity of the power battery; The wireless communication unit is connected to the charge and discharge control unit and the cloud platform, and is used to realize communication between the charge and discharge control unit and the cloud platform; The industrial control unit is connected to the charge and discharge control unit and the cloud platform, and is used to realize charging and discharging, and display the process information of charging and discharging; and is used to collect, record and analyze the charging and discharging communication messages in real time; The cloud platform is connected to the wireless communication unit and the industrial control unit, and is used to obtain all information during the charging and discharging process, and to obtain all information obtained by the charging and discharging control unit.

2. An electric vehicle intelligent charging and discharging test device according to claim 1, characterized in that: The industrial control unit includes: a charge and discharge control module, a charge and discharge electromagnetic compatibility test control module, a charge and discharge compatibility diagnosis module and a power battery status evaluation module; The charge and discharge control module is used to receive preset charge and discharge current values, control charging and discharging, and display charge and discharge information; The charge and discharge electromagnetic compatibility test control module is used to realize the control of charge and discharge and the size of charge and discharge current, control the enabling or disabling of the insulation monitoring unit, and display the charge and discharge information; A charge and discharge compatibility diagnosis module, used to automatically record the communication messages during the charge and discharge process, and provide a compatibility diagnosis result based on the communication messages; The power battery status assessment module is used to automatically record the characterization parameters of the power battery and perform power battery status analysis based on the characterization parameters of the power battery.

3. An electric vehicle intelligent charging and discharging test device according to claim 2, characterized in that: The charge and discharge control module comprises: The charge and discharge parameter setting submodule is used to set the charge and discharge parameters, including the charge and discharge current value and the charge and discharge cut-off SOC; The charge and discharge information display submodule is used to display the parameters during the charge and discharge process, including the charge and discharge voltage, charge and discharge current, battery SOC, and the power terminal temperature in the charge and discharge connection unit.

4. An electric vehicle intelligent charging and discharging test device according to claim 3, characterized in that: The charge and discharge electromagnetic compatibility test control module includes: The test parameter setting submodule is used to set the charge and discharge current values ​​according to the test requirements; A function control submodule, used to shut down or enable the insulation monitoring unit according to test requirements; The charge and discharge information display submodule is used to display the parameters during the charge and discharge process.

5. An electric vehicle intelligent charging and discharging test device according to claim 4, characterized in that: The charge and discharge compatibility diagnostic module includes: A charge and discharge data processing submodule, connected to the charge and discharge connection unit via the message reading unit, for real-time collection, recording and analysis of charge and discharge communication messages; The compatibility analysis submodule is used to analyze the timing of the charging and discharging communication messages, whether there are problems with the message filling content, and to carry out charging and discharging compatibility analysis; The charge and discharge information display submodule is used to display the parameters during the charge and discharge process.

6. An electric vehicle intelligent charging and discharging test device according to claim 5, characterized in that: The power battery status assessment module includes: A data processing submodule, connected to the charge and discharge connection unit through the message reading unit, for real-time acquisition, recording and analysis of the power battery characterization parameters extracted from the charge and discharge communication message, and the charge and discharge ambient temperature acquired in real time by the temperature acquisition unit; The state analysis submodule has a built-in power battery state analysis model and algorithm, and performs battery state analysis based on the data collected by the data processing submodule.

7. An electric vehicle intelligent charging and discharging test device according to claim 1, characterized in that: The insulation monitoring unit remains in an open state during normal charging and discharging, and remains in a closed state during the DC charging electromagnetic compatibility test.

8. An electric vehicle intelligent charging and discharging test device according to claim 1, characterized in that: The electric vehicle intelligent charging and discharging test device also includes: a temperature acquisition unit; The temperature acquisition unit is connected to the charge and discharge control unit and is used to acquire the ambient temperature conditions of the charge and discharge in real time.

9. An electric vehicle intelligent charging and discharging test method, performed by an electric vehicle intelligent charging and discharging test device according to any one of claims 1 to 8, characterized in that: Specifically include: The precise control test of charge and discharge includes the following steps: Input a preset charging current value or a preset discharging current value through the charging and discharging control module in the industrial control unit; The charge and discharge control module determines the actual current value according to the preset charge current value or the preset discharge current value and the protection strategy; wherein the protection strategy is: according to the preset charge current value or the preset discharge current value, the power battery charge and discharge current demand value, and the power battery 1C charge and discharge current value, the minimum value is selected as the actual current value; The charge and discharge control unit sends the actual current value to the bidirectional AC / DC power conversion unit to achieve accurate charge and discharge; The charge and discharge compatibility evaluation test includes the following steps: Insert the charging and discharging connection unit into the vehicle to be tested to charge or discharge the vehicle to be tested; The communication messages during the charging and discharging process are automatically recorded through the charging and discharging compatibility diagnosis module in the industrial control unit; The communication messages recorded during the current charging and discharging process are compared with the charging and discharging compatibility database built into the industrial control unit to obtain the compatibility diagnosis result; The power battery status assessment test includes the following steps: Insert the charging and discharging connection unit into the vehicle to be tested; The initial SOC value before charging or discharging starts is recorded by the power battery status evaluation module in the industrial control unit; Charging or discharging the vehicle to be tested for a preset time according to the current SOC state of the vehicle to be tested, and recording a cut-off SOC value after charging or discharging stops; Calculate the health status of the power battery; The DC charging electromagnetic compatibility test includes the following steps: The insulation monitoring unit is controlled to be turned off through the charge and discharge electromagnetic compatibility test control module in the industrial control unit; Input a preset charging current value or a preset discharging current value through the charging and discharging electromagnetic compatibility test control module in the industrial control unit; The charge and discharge electromagnetic compatibility test control module determines the actual current value according to the preset charge current value or the preset discharge current value and the protection strategy; The charge and discharge control unit sends the actual current value to the bidirectional AC / DC power conversion unit to achieve accurate charge and discharge and perform a DC charging electromagnetic compatibility test.

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