A new energy vehicle charging detection system and method

Abstract

The application is suitable for the technical field of safety detection, and provides a new energy automobile charging detection system and method. The system comprises a signal acquisition and processing subsystem, an operation control subsystem, a power output subsystem and an execution mechanism. The signal acquisition and processing subsystem acquires charging data of a vehicle in real time and sends the charging data to a microcontroller in the operation control subsystem. The microcontroller comprises a direct current charging control unit, an alternating current charging control unit, a direct current charging operation unit and an alternating current charging operation unit. The alternating current / direct current charging operation unit calculates the charging data and outputs a detection result. Based on the detection result, the alternating current / direct current charging control unit sends alternating current / direct current charging and alternating current / direct current output power adjustment instructions to the power output subsystem. After receiving the charging instructions, the power output subsystem performs power output according to preset charging conditions. The execution mechanism executes the action of power output. The application can realize rapid charging detection of a new energy automobile.

Description

Technical Field

[0001] This application belongs to the field of safety testing technology, and in particular relates to a new energy vehicle charging testing system and method. Background Technology

[0002] With the green energy revolution in the automotive industry, my country's production, sales and ownership of new energy vehicles have jumped to the top in the world. In recent years, the production and sales of new energy vehicles in China have generally been on the rise. In particular, in 2021, my country's sales of new energy vehicles reached 3.521 million units, and the cumulative ownership of new energy vehicles in China reached 7.84 million units. New energy vehicles will be the main direction of automotive development for a long time to come.

[0003] The operational safety of new energy vehicles is becoming increasingly prominent, with fires and explosions occurring in various states, including driving, parking, and charging, on the rise. This necessitates new requirements for testing methods. Currently, only a portion of the specific testing items for new energy electric vehicles are conducted before the vehicles leave the production line at the OEM, and these methods are complex, time-consuming, and inefficient, making them unsuitable for the periodic inspection of in-use vehicles. In addition to the reliance on traditional braking, skid, and lighting tests for in-use vehicles, more critical safety testing has shifted to the testing of the three key electrical systems unique to new energy vehicles, especially charging and discharging tests.

[0004] When a vehicle is charging, its electronic control system, battery, and management system are involved. Testing the vehicle requires simulating parts of the charging process and, in the shortest possible time, collecting data from the battery, simulating various abnormal faults, and triggering the vehicle's protection mechanisms. Currently, there is no commercially available solution for this type of fast-charging testing. Summary of the Invention

[0005] To overcome the problems existing in related technologies, this application provides a new energy vehicle charging detection system and method, which can simulate part of the vehicle charging process by preset charging conditions, so that charging and detection can be carried out simultaneously, and realize fast charging detection.

[0006] This application is achieved through the following technical solution:

[0007] In a first aspect, embodiments of this application provide an AC / DC charging detection system for new energy electric vehicles, the system comprising a signal acquisition and processing subsystem, a calculation and control subsystem, a power output subsystem, and an actuator;

[0008] The signal acquisition and processing subsystem is used to acquire vehicle charging data in real time and send the charging data to the microcontroller in the computing and control subsystem; the charging data includes DC charging data and AC charging data; the microcontroller includes a DC charging control unit, an AC charging control unit, a DC charging computing unit, and an AC charging computing unit.

[0009] The computational control subsystem is configured to, after the microcontroller receives the DC charging data, have the DC charging computation unit perform calculations and status judgments on the DC charging data and output a first detection result; based on the first detection result, have the DC charging control unit issue a DC charging command to the power output subsystem; and is further configured to, after the microcontroller receives the AC charging data, have the AC charging computation unit perform calculations and status judgments on the AC charging data and output a second detection result; based on the second detection result, have the AC charging control unit issue an AC charging command to the power output subsystem.

[0010] The power output subsystem is used to output power according to a preset charging condition after receiving the DC charging command or the AC charging command.

[0011] The actuator is used to connect the vehicle to the power output subsystem and perform the power output action; it is also used to connect the vehicle to the signal acquisition and processing subsystem.

[0012] In one possible implementation, the signal acquisition and processing subsystem includes: a converter, a DC current sensor, a DC voltage sensor, a DC leakage current sensor, a connection confirmation level sampling unit, an AC current sensor, and an AC voltage sensor.

[0013] The converter is used for communication and sensing between the new energy vehicle charging detection system and the vehicle; the DC current sensor is used to collect the DC charging current of the vehicle in real time; the DC voltage sensor is used to collect the DC charging voltage of the vehicle in real time; the DC leakage current sensor is used to collect the DC charging leakage current of the vehicle in real time; the connection confirmation level sampling unit is used to collect the first connection confirmation level signal between the vehicle and the DC charging gun and the second connection confirmation level signal between the vehicle and the AC charging gun in real time; the AC current sensor is used to collect the AC charging current of the vehicle in real time; the AC voltage sensor is used to collect the AC charging voltage of the vehicle in real time.

[0014] The power output subsystem includes a programmable power supply; the programmable power supply includes a programmable DC power supply and a programmable AC power supply; the programmable DC power supply is used for power output under the DC charging command; the programmable AC power supply is used for power output under the AC charging command.

[0015] The actuator includes a DC gun thread control unit and an AC gun thread control unit; the DC gun thread control unit is used to control the DC gun to charge the vehicle end and is used for signal transmission between the signal acquisition and processing subsystem and the vehicle end; the AC gun thread control unit is used to control the AC gun to charge the vehicle end and is used for signal transmission between the signal acquisition and processing subsystem and the vehicle end.

[0016] In one possible implementation, the connection confirmation level sampling unit is further configured to send the first connection confirmation level signal to the DC charging control unit and the second connection confirmation level signal to the AC charging control unit; the DC charging control unit issues a start charging command to the power output subsystem based on the first connection confirmation level signal; and the AC charging control unit issues a start charging command to the power output subsystem based on the second connection confirmation level signal.

[0017] In one possible implementation, the microcontroller further includes an over-temperature alarm control unit;

[0018] The over-temperature alarm control unit is used to issue an alarm when the temperature at the new energy vehicle charging detection system or the vehicle exceeds the corresponding threshold.

[0019] In one possible implementation, the converter is also used to connect the microcontroller and the signal acquisition and processing subsystem; the converter, the host computer, the vehicle, the programmable power supply, and the microcontroller form a bus communication network; the bus communication network is used for data interaction and command transmission between the new energy vehicle charging detection system and the vehicle under test during the detection process.

[0020] Secondly, embodiments of this application provide a method for detecting charging of new energy vehicles, the method comprising:

[0021] After receiving a DC detection command from the host computer, the microcontroller in the computational control subsystem establishes a DC charging control process and a DC charging computation process under a preset DC charging condition; it charges the vehicle according to the DC charging control process; and it transmits the first detection result of the DC charging computation process back to the host computer according to the first detection result of the DC charging computation process.

[0022] After receiving an AC detection command from the host computer, the microcontroller in the computational control subsystem establishes an AC charging control process and an AC charging computation process under a preset AC charging condition. Based on the second detection result of the AC charging computation process, the microcontroller transmits the second detection result of the AC charging computation process back to the host computer.

[0023] In one possible implementation, the establishment of the DC charging control process includes: a connection confirmation level sampling unit in the signal acquisition and processing subsystem acquires a first connection confirmation level signal between the DC gun and the vehicle, and sends the first connection confirmation level signal to the DC charging control unit in the microcontroller; the DC charging control unit issues a start charging command to the programmable DC power supply in the power output subsystem.

[0024] The establishment of the DC charging calculation process includes: after the DC charging calculation unit in the microcontroller receives the DC charging data collected in real time by the signal acquisition and processing subsystem, the DC charging calculation unit calculates and judges the state of the DC charging data and outputs the first detection result; based on the first detection result, the DC charging control unit sends a charging command to the power output subsystem according to the preset DC charging conditions.

[0025] The establishment of the AC charging control process includes: the connection confirmation level sampling unit in the signal acquisition and processing subsystem acquires the second connection confirmation level signal between the AC gun and the vehicle, and sends the second connection confirmation level signal to the AC charging control unit in the microcontroller; the AC charging control unit sends a start charging command to the programmable AC power supply in the power output subsystem to establish the AC charging control process.

[0026] The establishment of the AC charging calculation process includes: after the AC charging calculation unit in the microcontroller receives the AC charging data collected in real time by the signal acquisition and processing subsystem, the AC charging calculation unit performs calculation and status judgment on the AC charging data and outputs the second detection result; based on the second detection result, the AC charging control unit issues a charging command to the power output subsystem according to the preset AC charging conditions.

[0027] In one possible implementation, collecting the DC charging data includes:

[0028] The DC current sensor, DC voltage sensor, and DC leakage current sensor of the signal acquisition and processing subsystem acquire DC charging data. After signal processing and AD conversion, the DC charging data is sent to the microcontroller.

[0029] In one possible implementation, collecting the AC charging data includes:

[0030] The AC current sensor, AC voltage sensor, and AC leakage current sensor of the signal acquisition and processing subsystem acquire AC charging data. After signal processing and AD conversion, the AC charging data is sent to the microcontroller.

[0031] During signal processing and AD conversion, within the data range used by the system, data is averaged and filtered using data acquired at a preset frequency and within a preset range; during data calibration, a two-point calibration is selected for the useful data range, without using the zero point.

[0032] In one possible implementation, the preset DC charging conditions include an initial phase, a general phase, and an abnormal phase.

[0033] The initial phase is used for resistance detection, voltage detection, and charging circuit anomaly detection when the microcontroller confirms the connection confirmation level signal.

[0034] The general phase involves dividing the DC charging control process and the AC charging control process into multiple current ranges for multiple item detections during execution; these multiple item detections include voltage consistency, temperature consistency, voltage accuracy, charging leakage current, and communication message anomaly detection.

[0035] The abnormal phase is the shutdown phase due to insulation faults, and is used for testing to verify the insulation monitoring function.

[0036] The beneficial effects of the embodiments in this application compared with the prior art are:

[0037] In this embodiment of the application, under a preset charging condition, the operation control subsystem uses an AC / DC charging control unit and an AC / DC charging operation unit to combine the preset charging condition so that charging and detection can be performed simultaneously, thereby enabling fast charging detection.

[0038] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this specification. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a structural diagram of a new energy vehicle charging detection system provided in an embodiment of this application;

[0041] Figure 2 This is a schematic diagram of the composition and signal transmission of some subsystems in a new energy vehicle charging detection system provided in an embodiment of this application;

[0042] Figure 3 This is a schematic diagram of a preset DC charging condition provided in an embodiment of this application;

[0043] Figure 4 This is a DC charging control flowchart provided in one embodiment of this application;

[0044] Figure 5 This is a flowchart of DC charging operation provided in an embodiment of this application;

[0045] Figure 6 This is a flowchart of insulation detection during DC charging provided in one embodiment of this application;

[0046] Figure 7 This is an AC charging control flowchart provided in one embodiment of this application;

[0047] Figure 8 This is a flowchart of AC charging operation provided in an embodiment of this application. Detailed Implementation

[0048] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0049] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0050] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0051] It should also be understood that the term "relative" as used in this application specification and appended claims refers to relative positions in mechanical motion.

[0052] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0053] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0054] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0055] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0056] Figure 1 This is a structural diagram of a new energy vehicle charging detection system. The AC / DC charging detection method for new energy electric vehicles in this invention is implemented based on this system.

[0057] In one embodiment, reference is made to Figure 1 and Figure 2 A new energy vehicle charging detection system, characterized in that it includes: a signal acquisition and processing subsystem, a calculation and control subsystem, a power output subsystem, and an actuator.

[0058] The signal acquisition and processing subsystem is used to acquire vehicle charging data in real time and send the charging data to the microcontroller in the computing and control subsystem. The charging data includes DC charging data and AC charging data. The microcontroller includes a DC charging control unit, an AC charging control unit, a DC charging computing unit, and an AC charging computing unit.

[0059] The computational control subsystem is used to, after the microcontroller receives DC charging data, have the DC charging computation unit perform calculations and status judgments on the DC charging data and output a first detection result; based on the first detection result, the DC charging control unit sends a DC charging command to the power output subsystem; it is also used to, after the microcontroller receives AC charging data, have the AC charging computation unit perform calculations and status judgments on the AC charging data and output a second detection result; based on the second detection result, the AC charging control unit sends an AC charging command to the power output subsystem.

[0060] The power output subsystem is used to output power according to preset charging conditions after receiving a DC charging command or an AC charging command.

[0061] The actuator is used to connect the vehicle to the power output subsystem and perform power output actions; it is also used to connect the vehicle to the signal acquisition and processing subsystem.

[0062] Specifically, the signal acquisition and processing subsystem includes: a converter, a DC current sensor, a DC voltage sensor, a DC leakage current sensor, a connection confirmation level sampling unit, an AC current sensor, and an AC voltage sensor. The converter is used for communication and sensing between the new energy vehicle charging detection system and the vehicle. The DC current sensor is used to acquire the vehicle's DC charging current in real time. The DC voltage sensor is used to acquire the vehicle's DC charging voltage in real time. The DC leakage current sensor is used to acquire the vehicle's DC charging leakage current in real time. The connection confirmation level sampling unit is used to acquire the first connection confirmation level signal between the vehicle and the DC charging gun and the second connection confirmation level signal between the vehicle and the AC charging gun in real time. The AC current sensor is used to acquire the vehicle's AC charging current in real time. The AC voltage sensor is used to acquire the vehicle's AC charging voltage in real time.

[0063] For example, the signal acquisition and processing subsystem acquires in real time the vehicle-side DC charging voltage, DC charging current, DC charging leakage current, DC gun connection confirmation level signal, power battery and power platform voltage, AC charging voltage, AC charging current, AC gun connection confirmation level signal, AC gun control guidance level and pulse signal, etc., and performs current-to-voltage conversion, filtering, amplification and isolation processing through its own signal processing function block.

[0064] The power output subsystem includes a programmable power supply; the programmable power supply includes a programmable DC power supply and a programmable AC power supply; the programmable DC power supply is used for power output under DC charging commands; the programmable AC power supply is used for power output under AC charging commands.

[0065] The actuator includes a DC gun thread control unit and an AC gun thread control unit; the DC gun thread control unit is used to control the DC gun to charge the vehicle end and is used for signal transmission between the signal acquisition and processing subsystem and the vehicle end; the AC gun thread control unit is used to control the AC gun to charge the vehicle end and is used for signal transmission between the signal acquisition and processing subsystem and the vehicle end.

[0066] Specifically, the connection confirmation level sampling unit is also used to send the first connection confirmation level signal to the DC charging control unit and the second connection confirmation level signal to the AC charging control unit; the DC charging control unit sends a start charging command to the power output subsystem based on the first connection confirmation level signal; the AC charging control unit sends a start charging command to the power output subsystem based on the second connection confirmation level signal.

[0067] Specifically, the microcontroller also includes an over-temperature alarm control unit; the over-temperature alarm control unit is used to issue an alarm when the temperature at the charging detection system or vehicle end exceeds the corresponding threshold.

[0068] Specifically, the converter is also used to connect the microcontroller and the signal acquisition and processing subsystem; the converter, the host computer, the vehicle, the programmable power supply, and the microcontroller form a bus communication network; the bus communication network is used for data interaction and command transmission between the new energy vehicle charging test system and the vehicle under test during the testing process.

[0069] Next, based on the new energy vehicle charging detection system, the method for implementing new energy vehicle charging detection will be described in detail.

[0070] In one embodiment, based on a new energy vehicle charging detection system, the method for detecting DC charging of new energy vehicles is described in detail below:

[0071] After receiving the DC detection command from the host computer, the microcontroller in the computational control subsystem establishes a DC charging control process and a DC charging computation process under the preset DC charging conditions; it charges the vehicle according to the DC charging control process; it calculates the first detection result according to the DC charging computation process, and the microcontroller transmits the first detection result of the DC charging computation process back to the host computer.

[0072] Specifically, the DC charging data acquisition process includes: DC current sensor, DC voltage sensor, and DC leakage current sensor of the signal acquisition and processing subsystem acquiring DC charging data; after signal processing and AD conversion (Analog-to-Digital Convert), the DC charging data is sent to the microcontroller.

[0073] During signal processing and AD conversion, within the data range used by the system, data is sampled at a preset frequency and averaged within a preset range; during data calibration, a two-point calibration is selected for the useful data range, and zero points are not used.

[0074] For example, all sensor signals acquired must be processed by a signal processing unit and an AD conversion unit to convert them into digital signals that can be recognized by the microcontroller. Since the accuracy of sensor signals is one of the standards for result determination, it is crucial. Therefore, the data range used in this system was selected for signal processing and AD conversion. A high-frequency data acquisition and small-range data averaging filtering method was employed. Furthermore, a two-point calibration of the useful data range was used during calibration, without using the zero point, which represents the error range caused by circuit or sensor-specific factors.

[0075] Specifically, the preset DC charging operating conditions include an initial phase, a general phase, and an abnormal phase. The initial phase, when the microcontroller confirms the first connection confirmation signal, is used for resistance detection, voltage detection, and charging circuit anomaly detection. The general phase, during the execution of both DC and AC charging control flows, divides multiple current ranges for various tests; these tests include voltage consistency, temperature consistency, voltage accuracy, charging leakage current, and communication message anomaly detection. The abnormal phase is an insulation fault shutdown phase used for testing and verifying the insulation monitoring function.

[0076] For example, a preset DC charging operating condition includes 14 operating condition stages, such as... Figure 3 As shown in the diagram, the output current values ​​for stages 3, 7, and 10 are likely to differ during actual charging. Under normal temperature conditions, when most vehicles' SOC is between 20% and 80%, the requested current I... Q It gradually increases, so from the time axis perspective, the actual current in stages 3, 7, and 11 should show an upward trend; however, it is simultaneously limited by the system output current I. max Therefore, in stage 3, when charging with the smaller of the two values, the charging result is usually not a straight line.

[0077] Figure 3 In the middle, the peak values ​​of stages 3, 7, and 11 are different, and the upward surge amplitude of stages 2, 6, and 10 is also different.

[0078] The parameters for each stage of this working condition are shown in Table 1.

[0079] Table 1 Preset DC charging condition parameters

[0080]

[0081] In Table 1: I Q Request current for BMS, I max The maximum output current of the device; I set Current is limited for the test item. Among them, (I) Q |I max )min~I set The range of charging current is represented by the BMS requested current I. Q and the device's maximum output current I max The minimum of the two values ​​is the current limit I of the detection item. set .

[0082] Phase 1 is the initial phase, which includes DC charging connection confirmation and connection establishment before charging. The tests that can be performed include R4 resistance detection, CC2 voltage detection, and charging circuit anomaly detection.

[0083] For example, resistor R4 is embedded in the vehicle's DC charging socket and is used for confirming the connection of the charging station. Its resistance is fixed at 1kΩ. CC2 is the vehicle connection confirmation line, used for vehicle detection and connection confirmation with the charging station. The vehicle confirms whether the charging gun is plugged in by detecting changes in its voltage level.

[0084] Stages 2 through 13 are general stages, including power output and regulation stages, and can detect voltage consistency, temperature consistency, voltage accuracy, charging leakage current, and communication message anomalies.

[0085] Phases 13 and 14 are abnormal phases, which involve causing insulation faults and shutdowns, and testing to verify the insulation monitoring function.

[0086] The current status at each stage of operation is dynamically adjusted according to the vehicle's BMS (Battery Management System), thereby achieving rapid testing based on general vehicle model testing.

[0087] For example, calculating the vehicle BMS voltage accuracy in a DC charging testing project includes:

[0088] pass

[0089]

[0090] Calculate the vehicle BMS voltage accuracy in the DC charging test project; where U acc For voltage measurement accuracy, U x To measure voltage in the detection system, U y For BMS voltage measurement, n is the number of sampling points, where n-2≥1.

[0091] During DC charging phase 5, the accuracy of calculating the vehicle BMS current includes:

[0092] pass

[0093]

[0094] Calculate the accuracy of the vehicle BMS current; where I acc For current measurement accuracy, I x To measure the current in the detection system, I y For measuring current in a BMS, n is the number of sampling points, where n-2≥1.

[0095] Specifically, the DC charging control process is established, including: the connection confirmation level sampling unit in the signal acquisition and processing subsystem acquires the first connection confirmation level signal between the DC gun and the vehicle, and sends the first connection confirmation level signal to the DC charging control unit in the microcontroller; the DC charging control unit sends a start charging command to the programmable DC power supply in the power output subsystem.

[0096] For example, the DC gun connection confirmation level signal, DC charging voltage, and DC charging current are input to the DC charging control unit. The DC charging control unit, in conjunction with the DC power supply of the power output subsystem and the DC gun thread control unit of the actuator, establishes the DC charging control process.

[0097] Among them, such as Figure 4 As shown, the DC charging control process is as follows: The DC_Connect function is used to confirm the DC charging connection. This confirmation process includes driving the opening and closing of corresponding switches, acquiring connection confirmation signals, and driving the electronic lock to lock and unlock, etc., to implement the connection confirmation process between the DC charging gun and the vehicle. After connection confirmation, the charging detection system interacts with the vehicle based on CHM, CRM, CTS, CML, and CRO, waiting for the DC charging voltage. CHM, CRM, CTS, CML, and CRO are abbreviations for the message names of the charging handshake stage and charging configuration stage interactions between charging facilities and vehicles in GB27930. CHM is used to issue the protocol version number, CRM is used to acquire charger identification, CTS is used for time synchronization, CML is the maximum capacity output message of the charging pile to estimate the remaining charging time, and CRO is the message sent by the charger to the BMS indicating that the output is ready. Next, it is determined whether the DC charging voltage DC_SenorValue is equal to the battery voltage. DC_SenorValue is a parameter of the DC voltage sensor, which is located near the vehicle end and outside the DC contactor. When it is detected that DC_SenorValue is equal to the battery voltage, it means that the charging detection system can charge the vehicle. Then, the DC charging control unit sends a start charging command to the programmable DC power supply in the power output subsystem, closes the DC contactor K1 / K2, and starts charging.

[0098] During the charging process, detection is performed by registering detection items and recording data when executing charging detection conditions. Next, it checks whether the DC charging voltage (DC_SenorValue) and DC charging current (DC_CurrentValue) are normal. DC_CurrentValue is a parameter of the DC current sensor, which is located on the DC charging bus and collects the charging current of the charging circuit. When both DC_SenorValue and DC_CurrentValue are normal, communication with the vehicle is disconnected, charging is stopped, and detection ceases. If either DC_SenorValue or DC_CurrentValue is abnormal, the DC charging control process ends.

[0099] The DC charging operation process is established as follows: after receiving the DC charging data collected in real time by the signal acquisition and processing subsystem in the microcontroller, the DC charging operation unit calculates and judges the DC charging data and outputs the first detection result; based on the first detection result, the DC charging control unit sends a charging command to the power output subsystem according to the preset DC charging conditions.

[0100] For example, after the DC charging process is established, when detection is performed during the DC charging process, the DC charging leakage current, power battery and electric platform voltage are transmitted to the DC charging calculation unit for the calculation and judgment of the first detection result, and the DC charging calculation process is established.

[0101] Among them, such as Figure 5 As shown, the DC charging operation process is as follows: When both DC_SenorValue and DC_CurrentValue are normal, voltage, current, and leakage current are acquired in preset DC charging condition stages 2 to 14, and their equivalent values ​​are saved; it is determined whether to enter preset DC charging condition stage 5; when entering preset DC charging condition stage 5, DC_CurrentValue and BMS_DCCurrentValue are acquired at 250ms intervals until the end of the above condition stage 5. BMS_DCCurrentValue is the DC charging current detected by the vehicle end and transmitted back by the vehicle battery management system. When condition stage 5 ends, the current accuracy is calculated; then, the detection continues according to the preset DC charging condition to determine whether preset DC charging condition stage 14 has ended; when preset DC charging condition stage 14 ends, all data of the preset DC charging condition stage are statistically analyzed, the maximum leakage current value is filtered, and the voltage accuracy and loop voltage drop are calculated.

[0102] In the preset DC charging conditions 4 and 5, the duration of each segment is different. In the actual test, stage 5 is the initial current accuracy measurement, while stage 9 is the repeated current accuracy measurement. Moreover, the test is repeated after reducing the current under different peak conditions in stages 3 and 7, in order to ensure the repeatability and accuracy of the test results.

[0103] When testing battery temperature and voltage consistency, it is necessary to create conditions that cause significant changes in the voltage and temperature of individual power battery cells. Dynamic current conditions can cause changes in battery temperature, and continuous high current in stage 11 can also cause significant changes in battery voltage and temperature. This can detect whether there are faults such as poor battery consistency.

[0104] In stage 13, an insulation fault is created, which means creating a non-insulated condition between the power battery and the vehicle's electrical platform (frame) so that the vehicle can detect it and trigger an alarm. If this is created at high current, it is easy to cause damage to the device and short circuits that could injure people. Moreover, the insulation monitoring function mainly detects voltage. As long as the voltage does not meet the standard, it can be verified whether the function is normal or not. There is no need to perform the test at high power.

[0105] For example, such as Figure 6 As shown, the insulation fault detection process is as follows: Upon entering stage 13, the DC charging processing unit determines whether to perform an insulation test. If an insulation test signal is received, the power battery voltage is acquired, the connection resistance is calculated, and this resistance is connected to the circuit. Then, it is determined whether insulation fault information is transmitted back from the vehicle. If insulation fault information is transmitted back, the aforementioned connection resistance is disconnected. Then, the DC charging processing unit determines whether to detect leakage current. If not, the test process ends. If leakage current is detected, the maximum value of the leakage current sensor data from stages 2 to 13 is compared with the preset leakage current threshold.

[0106] For example, this embodiment uses a non-standard charging gun to simulate the DC charging setup process. After DC charging is established, it can measure the vehicle's R4 resistance, vehicle CC2 voltage, vehicle K5K6 contactor adhesion status, the accuracy of voltage and current at both ends of the power battery, vehicle insulation fault monitoring function, and abnormal communication messages. This new energy vehicle charging detection method has the characteristics of fast response speed, multiple detection items, short time, high accuracy, and easy expansion.

[0107] In another embodiment, based on the new energy vehicle charging detection system, the method for detecting AC charging of new energy vehicles is described in detail below:

[0108] After receiving the AC detection command from the host computer, the microcontroller in the arithmetic control subsystem establishes the AC charging control process and the AC charging calculation process under the preset AC charging conditions. Based on the second detection result of the AC charging calculation process, the microcontroller transmits the second detection result of the AC charging calculation process back to the host computer.

[0109] Specifically, the AC charging data is collected through the AC current sensor, AC voltage sensor, and AC leakage current sensor of the signal acquisition and processing subsystem. After signal processing and AD conversion, the AC charging data is sent to the microcontroller.

[0110] During signal processing and AD conversion, within the data range used by the system, data is sampled at a preset frequency and averaged within a preset range; during data calibration, a two-point calibration is selected for the useful data range, and zero points are not used.

[0111] For example, all sensor signals acquired must be processed by a signal processing unit and an AD conversion unit to convert them into digital signals that can be recognized by the microcontroller. Since the accuracy of sensor signals is one of the standards for result determination, it is crucial. Therefore, the data range used in this system was selected for signal processing and AD conversion. A high-frequency data acquisition and small-range data averaging filtering method was employed. Furthermore, a two-point calibration of the useful data range was used during calibration, without using the zero point, which represents the error range caused by circuit or sensor-specific factors.

[0112] Specifically, the preset AC charging conditions include disconnecting the vehicle charging communication S2 switch, changing the vehicle charging connection confirmation CC voltage, changing the vehicle PWM frequency duty cycle, disconnecting the charging communication S3 switch or control guidance CP signal or charging connection confirmation CC line at the charging facility end.

[0113] The AC charging control process is established, including: the connection confirmation level sampling unit in the signal acquisition and processing subsystem acquires the second connection confirmation level signal between the actuator and the vehicle, and sends the second connection confirmation level signal to the AC charging control unit in the microcontroller; the AC charging control unit sends a start charging command to the programmable AC power supply in the power output subsystem.

[0114] For example, the AC charging gun connection confirmation level signal, the AC charging gun control guidance level signal, and the pulse signal are input to the AC charging control unit. The AC charging control unit, in conjunction with the AC power supply of the power output subsystem and the AC charging gun thread control unit of the actuator, establishes the AC charging control process.

[0115] Among them, such as Figure 7As shown, the AC charging control flow is as follows: The AC_Connect function is used to confirm the AC charging connection. This confirmation process includes driving the opening and closing of corresponding switches and acquiring connection confirmation signals, which are used to implement the connection confirmation process between the AC charging gun and the vehicle. After connection confirmation, the voltage monitoring function Check_PointValue is used to detect the interaction between the system and the vehicle's PWM. Check_PointValue is used to detect the duty cycle and amplitude of the PWM generated by the control guidance signal during AC charging; and to determine whether the AC charging voltage AC_SenorValue is equal to the power supply voltage. AC_SenorValue is an AC voltage sensor parameter. When AC_SenorValue is detected to be equal to the power supply voltage, the AC charging control unit controls and adjusts the PWM duty cycle and fixes the adjusted duty cycle, sending a start charging command to the programmable AC power supply, so that the on-board charging system starts charging according to the output power provided by the charging detection system of this invention.

[0116] During charging, detection is performed by registering detection items and recording data when executing charging detection conditions. Simultaneously, it checks whether the AC charging voltage AC_SenorValue and AC charging current AC_CurrentValue are normal. AC_CurrentValue is a parameter of the AC current sensor. When both AC_SenorValue and AC_CurrentValue are normal, communication with the vehicle is disconnected, charging is stopped, and detection ceases. If either AC_SenorValue or AC_CurrentValue is abnormal, the AC charging control process ends.

[0117] The AC charging operation process is established as follows: after receiving the AC charging data collected in real time by the signal acquisition and processing subsystem in the AC charging operation unit in the microcontroller, the AC charging operation unit performs calculations and status judgments on the AC charging data and outputs a second detection result; based on the second detection result, the AC charging control unit sends a charging command to the power output subsystem according to the preset AC charging conditions.

[0118] For example, after the AC charging process is established, when detection is performed during the charging process, the AC charging voltage and AC charging current are transmitted to the AC charging calculation unit for the calculation and judgment of the second detection result, thus establishing the AC charging calculation process.

[0119] Among them, such as Figure 8As shown, the AC charging operation process is as follows: When both AC_SenorValue and AC_CurrentValue are normal, the PWM duty cycle is adjusted, and the change in AC_CurrentValue is recorded. Then, the S3 switch / cc line / cp signal is disconnected. After the S3 switch / cc line / cp signal is disconnected, Check_PointValue is used to determine whether the AC charging voltage AC_SenorValue at the preset position is normal. If the AC charging voltage AC_SenorValue at the preset position is abnormal, it indicates that the vehicle has a corresponding protection action under the preset AC charging condition. Then, the AC charging current AC_CurrentValue at the preset position is checked to see if it is normal. If the AC charging current AC_CurrentValue at the preset position is abnormal, it indicates that the vehicle has a corresponding protection action under the preset AC charging condition. The vehicle status is then recorded, other switches are disconnected, and the detection is stopped. If the AC_SenorValue at the preset position is normal, or the AC_CurrentValue is normal, it indicates that the vehicle does not have a corresponding protection action under the preset AC charging condition. The vehicle status is then recorded, other switches are disconnected, and the detection is stopped.

[0120] For example, this embodiment uses a non-standard charging gun to simulate the AC charging setup process. After AC charging is established, it can measure the vehicle's S2 state, vehicle CC voltage, the relationship between PWM frequency duty cycle and charging current, and the vehicle protection action after the charging facility's S3 switch, CP signal, or CC line is disconnected. This new energy vehicle charging detection method has the characteristics of fast response speed, multiple detection items, short time, high accuracy, and easy expansion.

[0121] In another embodiment, the microcontroller automatically performs two types of tests according to the host computer's detection instructions, divided into two detection processes: DC charging and AC charging.

[0122] DC charging detection process: The host computer sends DC detection items and detection commands via RS232. The microcontroller acquires data from the DC series sensors, and combines the programmable DC power supply and DC charging gun harness to establish the DC charging process and implement the DC charging conditions. Then, the first detection result is calculated using the DC charging calculation method.

[0123] AC charging test process: The host computer sends AC test items and test commands via RS232. The microcontroller acquires data from the AC series sensors, and combines the AC power supply and AC charging gun wiring harness to establish the AC charging process and implement the AC test items. Then, the second test result is calculated using the AC charging calculation method.

[0124] The programmable power supply unit interacts with the microcontroller or host computer via communication. The unit can operate independently, has built-in safety mechanisms such as fault protection, and is easy to expand.

[0125] The power supply line goes to the vehicle under test via the charging gun line, and the low-voltage signal line and communication line of the microcontroller go to the vehicle via the charging gun line. The AC and DC charging gun lines are modified according to the actual invention so that they can be connected to the same vehicle at the same time for program-controlled switching and testing.

[0126] The new energy vehicle charging testing method adopted by the aforementioned new energy vehicle charging testing system has the advantage of being able to meet the AC and DC charging testing needs of various new energy electric vehicles with different power, battery capacity, and voltage platforms on the market. Simultaneously, it ensures efficient vehicle testing by combining preset rapid testing conditions. The signal acquisition and processing subsystem uses high-precision, high-sensitivity, strong anti-interference capabilities, and high / low voltage signal isolation sensors; the power output subsystem uses a programmable power supply module with a wide output range, high accuracy, strong scalability, and fast dynamic response; the actuator uses a non-standard programmable charging gun cable; the calculation and control subsystem uses a stable and reliable AC / DC charging control model and AC / DC charging calculation model; the AC / DC charging control unit includes the AC / DC charging control model. The entire system features wide coverage of vehicle models, broad testing function coverage, high testing accuracy, high speed, good stability, and strong power scalability.

[0127] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0128] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0129] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0130] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0131] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for detecting fast charging of new energy vehicles, characterized in that, include: The host computer sends a DC detection command and uses the preset DC charging conditions of the charging detection system to establish a DC charging control process and a DC charging calculation process. The vehicle is charged according to the DC charging control process; the first detection result of the DC charging calculation process is transmitted back to the host computer through the microcontroller of the charging detection system according to the first detection result of the DC charging calculation process. The DC charging conditions include: initial stage, general stage and abnormal stage; The initial stage is used for resistance detection, voltage detection, and charging circuit anomaly detection when the microcontroller confirms the first connection confirmation level signal. The resistor is embedded in the vehicle's DC charging socket and is used for charging pile connection confirmation signal confirmation. The voltage detection is CC2 voltage detection, where CC2 is the vehicle connection confirmation line. The vehicle confirms whether the charging gun is plugged in by detecting changes in its voltage level. The charging circuit anomaly detection detects the adhesion of the vehicle's K5 and K6 contactors, and confirms the charging circuit anomaly by detecting adhesion. The general phase, during the execution of the DC charging control process, divides multiple current ranges for multiple item detections; these multiple item detections include voltage consistency, temperature consistency, voltage accuracy, charging leakage current, and communication message anomaly detection. The abnormal stage is the insulation fault shutdown stage, which is used to create an insulation fault shutdown and conduct tests to verify the insulation monitoring function. The method of creating an insulation fault is to create a non-insulated working condition between the power battery and the vehicle electric platform, that is, by obtaining the power battery voltage, calculating the non-insulation resistance, and connecting the resistance to the circuit; it is determined whether there is insulation fault information returned from the vehicle end. If there is insulation fault information returned, the above-mentioned connected resistance is disconnected. The host computer sends an AC detection command and establishes an AC charging control process and an AC charging calculation process using the preset AC charging conditions of the charging detection system. Based on the second detection result of the AC charging calculation process, the microcontroller of the charging detection system transmits the second detection result of the AC charging calculation process back to the host computer.

2. The method for detecting fast charging of new energy vehicles as described in claim 1, characterized in that, The DC charging control process is established, including: the connection confirmation level sampling unit in the signal acquisition and processing subsystem acquires the first connection confirmation level signal between the DC gun and the vehicle and sends it to the DC charging control unit; the DC charging control unit sends a start charging command to the programmable DC power supply in the power output subsystem. The DC charging calculation process includes: after the DC charging calculation unit receives the DC charging data collected in real time by the signal acquisition and processing subsystem, it performs calculations and status judgments on the DC charging data and outputs a first detection result; based on the first detection result, the DC charging control unit issues a charging command to the power output subsystem according to a preset DC charging operating condition; the first detection result includes the results of maintaining the charging process and the results of the detection items during the initial stage, general stage, and abnormal stage of the vehicle detection process. The AC charging control process is established, including: the connection confirmation level sampling unit in the signal acquisition and processing subsystem acquires the second connection confirmation level signal between the AC gun and the vehicle, and sends it to the AC charging control unit; the AC charging control unit sends a start charging command to the programmable AC power supply in the power output subsystem; the second detection result includes the AC charging establishment process and the result of the charging maintenance process after establishment and the detection item results. The AC charging operation process includes: after receiving AC charging data collected in real time by the signal acquisition and processing subsystem in the microcontroller, the AC charging operation unit performs calculations and status judgments on the AC charging data and outputs a second detection result; based on the second detection result, the AC charging control unit issues a charging command to the power output subsystem according to a preset AC charging condition.

3. A new energy vehicle charging detection system, used to implement the new energy vehicle fast charging detection method according to any one of claims 1 to 2, for charging and detecting the vehicle; characterized in that, include: The signal acquisition and processing subsystem is used to acquire vehicle charging data in real time and send the charging data to the microcontroller in the computing and control subsystem; the charging data includes DC charging data and AC charging data; the microcontroller includes a DC charging control unit, an AC charging control unit, a DC charging computing unit, and an AC charging computing unit. The computational control subsystem is configured to, after the microcontroller receives the DC charging data, have the DC charging computation unit perform calculations and status judgments on the DC charging data and output a first detection result; based on the first detection result, have the DC charging control unit issue a DC charging command to the power output subsystem; and is further configured to, after the microcontroller receives the AC charging data, have the AC charging computation unit perform calculations and status judgments on the AC charging data and output a second detection result; based on the second detection result, have the AC charging control unit issue an AC charging command to the power output subsystem; the DC charging command includes a DC charging signal and a DC output power adjustment signal; the AC charging command includes an AC charging signal and an AC output power adjustment signal. The power output subsystem is used to output power according to the preset charging conditions after receiving the DC charging command or the AC charging command. An actuator is used to connect the vehicle to the power output subsystem and perform the power output action; it is also used to connect the vehicle to the signal acquisition and processing subsystem.

4. The new energy vehicle charging detection system as described in claim 3, characterized in that, The signal acquisition and processing subsystem includes: a converter, a DC current sensor, a DC voltage sensor, a DC leakage current sensor, a connection confirmation level sampling unit, an AC current sensor, and an AC voltage sensor. The converter is used for communication and sensing between the new energy vehicle charging detection system and the vehicle; the DC current sensor is used to collect the DC charging current of the vehicle in real time; the DC voltage sensor is used to collect the DC charging voltage of the vehicle in real time; the DC leakage current sensor is used to collect the DC charging leakage current of the vehicle in real time; the connection confirmation level sampling unit is used to collect the first connection confirmation level signal between the vehicle and the DC charging gun and the second connection confirmation level signal between the vehicle and the AC charging gun in real time; the AC current sensor is used to collect the AC charging current of the vehicle in real time; the AC voltage sensor is used to collect the AC charging voltage of the vehicle in real time. The power output subsystem includes a programmable power supply; the programmable power supply includes a programmable DC power supply and a programmable AC power supply; the programmable DC power supply is used for power output under the DC charging command; the programmable AC power supply is used for power output under the AC charging command. The actuator includes a DC gun thread control unit and an AC gun thread control unit; the DC gun thread control unit is used to control the DC gun to charge the vehicle end and is used for signal transmission between the signal acquisition and processing subsystem and the vehicle end; the AC gun thread control unit is used to control the AC gun to charge the vehicle end and is used for signal transmission between the signal acquisition and processing subsystem and the vehicle end.

5. The new energy vehicle charging detection system as described in claim 4, characterized in that, The connection confirmation level sampling unit is further configured to send the first connection confirmation level signal to the DC charging control unit and the second connection confirmation level signal to the AC charging control unit; the DC charging control unit issues a start charging command to the power output subsystem based on the first connection confirmation level signal; and the AC charging control unit issues a start charging command to the power output subsystem based on the second connection confirmation level signal.

6. The new energy vehicle charging detection system as described in claim 4, characterized in that, The converter is also used to connect the microcontroller and the signal acquisition and processing subsystem; the converter, the host computer, the vehicle, the programmable power supply, and the microcontroller form a bus communication network; the bus communication network is used for data interaction and command transmission between the new energy vehicle charging detection system and the vehicle under test during the detection process.

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