Charging pile and charging system integrated with power battery diagnosis function

Abstract

The application relates to the technical field of charging equipment, and particularly provides a charging pile integrated with a power battery diagnosis function and a charging system, which aims to solve the problem of how to improve the safety and stability of vehicle charging. To this end, the charging pile integrated with the power battery diagnosis function comprises a charging pile body, a main control board arranged in the charging pile body, a charging gun arranged on the charging pile body, and a diagnosis module and a charging module connected with the main control board respectively, the diagnosis module comprises a main control unit, an excitation signal generation module, a response signal processing module, a power supply module, a switching switch and a direct-current blocking capacitor arranged at an output end of the diagnosis module, the charging module comprises a trickle charging sub-module, the trickle charging sub-module is in communication connection with the main control board, and an LC filter circuit is arranged at an output end of the charging module. The application can not only prolong the service life of the battery, but also improve the safety and stability of the charging process.

Description

Technical Field

[0001] This application relates to the field of charging equipment technology, specifically providing a charging pile and charging system with integrated power battery diagnostic functions. Background Technology

[0002] DC charging piles are devices for charging new energy electric vehicles. Their input is three-phase alternating current, which is converted into DC power by an internal AC-DC converter and outputs DC power that matches the vehicle's voltage and current.

[0003] Vehicle batteries inevitably experience performance degradation and aging during long-term charging and discharging. Therefore, battery health monitoring is essential. Otherwise, during charging at the aforementioned charging stations, the battery may experience thermal runaway, potentially leading to fires or explosions. However, current technologies typically involve periodic testing of battery health using specialized equipment. Furthermore, the testing methods generally rely on measuring parameters such as voltage and current to predict or estimate the battery's health. This makes reliable battery health monitoring difficult to guarantee and prevents real-time monitoring during each charging cycle, creating potential safety hazards.

[0004] Accordingly, a new technical solution is needed in this field to solve the above problems. Utility Model Content

[0005] This application aims to solve the aforementioned technical problem, namely, how to improve the safety and stability of vehicle charging.

[0006] In a first aspect, this application provides a charging pile with integrated power battery diagnostic functions, characterized in that it includes a charging pile body, a main control board disposed within the charging pile body, a charging gun disposed on the charging pile body, and a diagnostic module and a charging module respectively connected to the main control board, wherein the diagnostic module includes:

[0007] The main control unit includes a communication unit, which is communicatively connected to the main control board via the communication unit.

[0008] An excitation signal generation module includes an adjustable sine wave generator, which is used to generate a sinusoidal AC signal;

[0009] The response signal processing module includes an impedance transformation unit and an amplitude-frequency and phase-frequency characteristic testing unit. The impedance transformation unit is used to condition the response signal returned by the target battery, and the amplitude-frequency and phase-frequency characteristic testing unit is used to acquire the conditioned response signal.

[0010] A power supply module, which provides DC power to the diagnostic module;

[0011] A switching switch is used to control the connection between the diagnostic module and the charging gun;

[0012] A DC blocking capacitor is disposed at the output terminal of the diagnostic module, and the DC blocking capacitor is used to isolate DC power.

[0013] The charging module includes a trickle charging submodule, which is communicatively connected to the main control board. The output terminal of the charging module is equipped with an LC filter circuit, which is used to suppress AC excitation signals and prevent AC excitation signals from interfering with trickle charging.

[0014] In one technical solution of the aforementioned charging pile, the excitation signal generation module further includes a programmable frequency selection network, which is used to filter and set the frequency point of the sinusoidal AC signal generated by the adjustable sine wave generator.

[0015] In one technical solution of the above-mentioned charging pile, multiple charging guns are provided, the number of ports of the switching switch is the same as the number of charging guns and corresponds one-to-one with each charging gun, and the number of charging modules is the same as the number of charging guns and corresponds one-to-one with each charging gun.

[0016] In one technical solution of the above-mentioned charging pile, the diagnostic module is connected in parallel with each of the charging modules, and each of the charging modules and the corresponding charging gun is provided with a DC contact switch to control the connection and disconnection between the charging module and the charging gun.

[0017] In one technical solution of the aforementioned charging pile, the charging pile adopts PLC communication.

[0018] In one technical solution of the aforementioned charging pile, the charging pile further includes:

[0019] A controller is used to control the connection or disconnection of the diagnostic module and the charging gun, and to control the connection or disconnection of the charging module and the charging gun.

[0020] In a second aspect, this application provides a charging system integrating power battery diagnostic functions, comprising:

[0021] The charging pile described in any one of the first aspects;

[0022] The main control board communicates with the battery management module via a communication module to upload the raw frequency response data collected by the diagnostic module to the battery management module, and diagnoses the state of the target battery through the battery management module.

[0023] In one technical solution of the above charging system, the battery management module includes:

[0024] A battery big data storage unit is used to store historical charging data of the target battery.

[0025] The battery diagnostic model storage unit diagnoses the state of the target battery based on the historical charging data, the raw frequency response data obtained by the diagnostic module, and the battery diagnostic model.

[0026] In one technical solution of the above charging system, the communication module is a 4G communication module.

[0027] In one technical solution of the above charging system, the battery management module is an on-board battery management module.

[0028] By integrating a diagnostic module into the charging pile, this application applies laboratory-grade EIS diagnostic technology to vehicle charging scenarios in an engineered and cost-effective manner. This enables the diagnosis of battery health status during charging, and then provides specific charging strategies (such as adjusting charging current and charging time) based on the diagnostic results. This not only enables real-time monitoring of the power battery's health status during charging, which helps improve battery lifespan, but also allows for the timely detection of battery health problems and the selective adjustment of charging strategies based on battery status, thereby preventing thermal runaway, fire, explosion, and other phenomena, and improving the safety and stability of the charging process.

[0029] After the charging station establishes a communication connection with the vehicle, the diagnostic module can operate in parallel with the charging module. Both modules can simultaneously access the battery circuit. While the charging module charges the battery in trickle charging mode, the diagnostic module diagnoses the battery's condition. If the diagnostic results indicate a normal battery health, the charging module switches to full-power charging mode after the diagnosis is complete. This improves the charging time issue caused by separate diagnostic and charging processes, reducing user waiting time and enhancing the user experience. If the diagnostic results indicate an abnormal battery health, charging stops after the diagnosis is complete. Since trickle charging occurs during the diagnostic process, it will not cause further damage to the battery. Attached Figure Description

[0030] The preferred embodiments of this application are described below with reference to the accompanying drawings, in which:

[0031] Figure 1 This is a system block diagram of a charging pile with integrated power battery diagnostic function according to an embodiment of this application. Detailed Implementation

[0032] Preferred embodiments of this application are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of this application and are not intended to limit the scope of protection of this application. Those skilled in the art can make adjustments as needed to adapt to specific application scenarios.

[0033] It should be noted that in the description of this application, terms such as "upper," "lower," "left," "right," "inner," and "outer," which indicate direction or positional relationship, are based on the direction or positional relationship shown in the accompanying drawings. These terms are used merely for ease of description and do not indicate or imply that the relevant device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, ordinal numbers such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0034] Furthermore, it should be noted that, in the description of this application, unless otherwise expressly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0035] To facilitate understanding of the technical solution of this application, the charging principle of the charging pile (the charging pile described in this application is a DC charging pile) and the existing methods for detecting the health status of power batteries will be briefly introduced first.

[0036] Before charging begins, the charging station must first establish a physical and communication connection with the vehicle. During this interaction, compatibility and charging parameters are automatically negotiated. After all data exchange is complete, both the vehicle and the charging station will activate their DC contactors to establish a physical connection between the charging station's internal AC-DC module and the vehicle's battery to transmit electrical energy. During this interaction, the physical connections of the vehicle's battery pack's DC+ (positive DC bus) and DC- (negative DC bus) terminals are obtained. In terms of communication, information such as the vehicle's battery's rated voltage, rated capacity, battery material, battery manufacturer, production date, individual cell voltage, current total voltage, highest individual cell voltage, state of charge, and temperature are obtained.

[0037] Currently, the health status testing of power batteries in this field generally requires placing the vehicle or battery at a dedicated testing station for individual battery testing. On the one hand, this method mostly involves periodic testing of the battery, making real-time monitoring during each charge cycle impossible. When the testing cycle is long, it's possible for a battery with existing health issues to continue charging using the original strategy, posing a significant safety hazard. Shortening the testing cycle, on the other hand, increases testing costs and consumes too much of the user's time. On the other hand, current methods for testing battery health status are mostly "predictive or extrapolative." For example, the ampere-hour integration method uses real-time measurement of the current flowing into and out of the battery, integrates the current to calculate the change in charge, and thus extrapolates the SOC (State of Charge). However, the accuracy and reliability of these methods are not high.

[0038] Based on this, this application proposes a solution that enables real-time diagnosis of battery health status during vehicle charging by integrating electrochemical impedance spectroscopy (EIS) testing into the charging pile.

[0039] Reference Figure 1 This is a system block diagram of a charging pile with integrated power battery diagnostic function according to an embodiment of this application.

[0040] The charging pile with integrated power battery diagnostic functions includes a charging pile body, a main control board, a charging gun, a diagnostic module, and a charging module. The charging gun is mounted on the charging pile body, while the main control board is located inside the charging pile body. The main control board is connected to both the diagnostic module and the charging module, which can selectively connect to the charging gun to diagnose or charge the battery.

[0041] It should be noted that the diagnostic module of this application is based on electrochemical impedance spectroscopy (EIS). Therefore, the diagnostic module includes a main control unit, an excitation signal generation module, a response signal processing module, a power supply module, and a switching switch. The main control unit is the "brain" of the entire diagnostic module. The main control unit includes a communication unit, which communicates with the main control board. For example, the main control board can send a command to the main control unit to begin diagnostics via a PLC.

[0042] The excitation signal generation module includes an adjustable sine wave generator and a programmable frequency selection network. The adjustable sine wave generator generates a sinusoidal AC signal, while the programmable frequency selection network filters and sets the frequency of the sinusoidal AC signal generated by the adjustable sine wave generator. For example, the main control unit precisely controls the adjustable sine wave generator to generate a low-voltage, low-current sinusoidal AC signal with adjustable amplitude and frequency through a 16-bit DAC, based on the required test frequency. The programmable frequency selection network (which can be composed of analog switches switching different combinations of resistors and capacitors) is then used to further precisely filter and set the frequency of the sinusoidal AC signal, ensuring that the excitation signal injected into the battery is pure and accurate.

[0043] The switching switch is used to control the connection between the diagnostic module and the charging gun. After receiving the relevant command, the switching switch establishes a connection between its port and the DC bus of the target battery, thereby injecting the aforementioned sinusoidal excitation signal into the target battery.

[0044] The response signal processing module includes an impedance transformation unit and an amplitude-frequency and phase-frequency characteristic testing unit. The impedance transformation unit is used to condition (such as amplify and filter) the response signal returned by the target battery. The amplitude-frequency and phase-frequency characteristic testing unit (the core of which is a 22-bit high-precision ADC analog front end) is used to acquire the conditioned response signal. The high resolution of 22 bits ensures that weak signal changes can be accurately measured.

[0045] The power supply module converts the input AC power into DC power, thereby providing a stable and isolated DC power supply for the various functional modules within the diagnostic module.

[0046] As described above, this application integrates a diagnostic module into the charging pile. After receiving a diagnostic command, the main control board controls an adjustable sine wave generator to produce an excitation signal. This excitation signal is then processed by a programmable frequency selection network and input to the target battery via a switching switch. The target battery's response signal (current or voltage response) to the excitation signal is then fed back to the impedance transformation unit and the amplitude-frequency and phase-frequency characteristic testing unit to acquire the response signal. Finally, the response signal is uploaded to the main control unit via the main control board to diagnose the battery's health status. The specific principle of the EIS test described above is well-known in the field and will not be elaborated upon here.

[0047] Thus, by integrating a diagnostic module into the charging pile, this application applies laboratory-grade EIS diagnostic technology to vehicle charging scenarios in an engineered and cost-effective manner. This enables the diagnosis of battery health status during charging, and then provides specific charging strategies (such as adjusting charging current and charging time) based on the diagnostic results. This not only enables real-time monitoring of the power battery's health status during charging, which is beneficial for improving battery lifespan, but also allows for the timely detection of battery health problems and the selective adjustment of charging strategies based on battery status, thereby preventing thermal runaway, fire, explosion, and other phenomena, and improving the safety and stability of the charging process.

[0048] On the other hand, this application uses electrochemical impedance spectroscopy for battery diagnosis, which is more accurate and reliable than existing methods that estimate health status by measuring current / voltage signals, thus enhancing credibility within the industry.

[0049] Furthermore, in one embodiment of this application, the charging module further includes a trickle charging submodule, which is communicatively connected to the main control board. After the charging pile and the vehicle establish a communication connection, the diagnostic module and the charging module can operate simultaneously. That is, in the initial stage of charging, the trickle charging submodule integrated in the charging module outputs a low-current DC power to charge in a "tricky charging" mode. At the same time, the feasibility of EIS diagnostics is implemented in parallel. After the diagnostic results are available, the system is dynamically adjusted to the optimal charging strategy, which can significantly shorten the user's perceived waiting time.

[0050] Therefore, considering that the excitation signal used by the diagnostic module is a small-current AC signal, while trickle charging uses a small-current DC signal, frequency isolation is required between the two. To prevent the AC excitation signal from the diagnostic module from interfering with trickle charging, an LC filter circuit is installed at the output of the charging module. The LC filter circuit is used to suppress the AC excitation signal and remove high-frequency noise. Simultaneously, a DC blocking capacitor is installed at the output of the diagnostic module to isolate the DC current from the charging module, preventing DC current from entering the circuit of the diagnostic module.

[0051] Thus, after establishing a communication connection between the charging station and the vehicle, the diagnostic module can operate in parallel with the charging module. Both modules can simultaneously access the battery circuit. While the charging module charges the battery in trickle charging mode, the diagnostic module diagnoses the battery's condition. If the diagnostic results indicate a normal battery health, the charging module switches to full-power charging mode after the diagnosis is complete. This improves the charging time issue caused by separate diagnostic and charging processes, reducing user waiting time and enhancing the user experience. If the diagnostic results indicate an abnormal battery health, charging stops after the diagnosis is complete. Since trickle charging occurs during the diagnostic process, it prevents further damage to the battery.

[0052] Reference Figure 1 In one implementation of this application, each charging pile body can be equipped with multiple charging guns. Correspondingly, the number of ports of the switching switch in the diagnostic module is the same as and corresponds one-to-one with the number of charging guns, and the number of charging modules is also the same as and corresponds one-to-one with the number of charging guns. For example, the figure illustrates two charging guns (charging gun A and charging gun B) as an example. Accordingly, the switching switch of the diagnostic module has two ports, port A and port B, and the charging modules include a first charging module and a second charging module.

[0053] Of course, in another implementation, the diagnostic module and the charging module can be operated separately. In this case, the diagnostic module and each charging module are connected in parallel, so that after the charging gun is connected to the vehicle battery, only one of the diagnostic module and the charging module is allowed to remain connected to the charging gun at any given time. That is, the diagnostic process and the charging process cannot be carried out at the same time. When the battery is being diagnosed, the charging module is disconnected, and when the battery is being charged, the diagnostic module is disconnected.

[0054] To achieve the above objectives, each charging module is equipped with a DC contact switch between itself and the corresponding charging gun. The two ports A and B of the switching switch are equipped with control switches K3 and K4, respectively. The connection between the diagnostic module and the corresponding charging pile is selectively connected or disconnected through switches K3 and K4. Figure 1 Each charging module has a DC contact switch K1 connected to its positive DC bus and a DC contact switch K2 connected to its negative DC bus. The output line of diagnostic module port A is connected to the end of DC contact switch K1 near charging gun A, and the output line of diagnostic module port B is connected to the end of DC contact switch K2 near charging gun B. This ensures that K1 / K2 of charging gun A and port A of diagnostic module are logically interlocked and cannot be closed simultaneously, and K1 / K2 of charging gun B and port B of diagnostic module are also logically interlocked and cannot be closed simultaneously. For example, when diagnosis is needed, port A is connected to charging gun A, and K1 / K2 is disconnected; when charging is needed, port A is disconnected from charging gun A, and K1 / K2 is closed.

[0055] To implement the above solution, a controller is installed inside the charging pile. The controller controls the connection or disconnection between the diagnostic module and the charging gun, as well as the connection or disconnection between the charging module and the charging gun.

[0056] Of course, the charging station is also equipped with a power distribution unit (i.e. Figure 1The DC power generated by the charging module (PK1 and PK2) is first connected to the power distribution unit through the positive (DC+) and negative (DC-) output terminals. The power distribution unit then switches the power transmission path. For example, when charging with charging gun A, the main control board controls the power distribution unit to engage PK1 and PK2 at the contacts leading to charging gun A. At this time, the power from the charging module is guided through PK1 / PK2 to the front end of the K1 / K2 switch on charging gun A. Once the K1 / K2 switch on charging gun A is closed, power can be delivered to the vehicle.

[0057] This application also discloses a charging system integrating power battery diagnostic functions, which includes a charging pile as described in any of the above embodiments, and a battery management module. The main control board of the charging pile is communicatively connected to the battery management module via a communication module. In one embodiment of this application, the battery management module is an on-board battery management module, that is, the battery management module is integrated into the vehicle's BMS system.

[0058] In one embodiment of this application, the communication module can be a 4G communication module. During the charging process of the vehicle, the health status of the target battery is first diagnosed by the diagnostic module. Specifically, the raw frequency response data collected by the diagnostic module is uploaded to the battery management module, and then the battery management module analyzes the frequency response data and calculates and determines the diagnostic result.

[0059] By centralizing diagnostic computing services locally (i.e., in the vehicle), signal interruption issues caused by network problems can be prevented.

[0060] In some embodiments, the battery management module includes a battery big data storage unit and a battery diagnostic model storage unit. The battery big data storage unit stores historical charging data of the target battery, and may also include EIS spectrum libraries for different brands and models of batteries, battery failure case data, etc. The battery diagnostic model storage unit inputs the received raw frequency response data into the battery diagnostic model and then obtains the diagnostic results.

[0061] For example, the execution steps of the battery diagnostic model storage unit may include:

[0062] Feature extraction: Extract key features (such as impedance values ​​at specific frequencies, relaxation time constants, etc.) from the uploaded raw frequency response data.

[0063] Model Analysis: Using machine learning and deep learning models, real-time data is compared and analyzed with historical charging data stored in the battery's big data storage unit. In practical applications, historical charging data from the battery's big data storage unit can be used to update the diagnostic model in real time, thereby improving the model's testing accuracy.

[0064] Fusion Diagnosis: By combining the vehicle's historical charging data (such as the trend of EIS changes in previous years), a longitudinal comparison is made to determine the rate of decline in battery state of health (SOH).

[0065] Report generation: Finally, the current battery health (SOH), internal short circuit risk, lithium plating risk and other indicators are calculated and a comprehensive diagnostic report is generated.

[0066] The technical solutions of this application have been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of this application.

Claims

1. A charging pile with integrated power battery diagnostic function, characterized in that, The system includes a charging pile body, a main control board disposed within the charging pile body, a charging gun disposed on the charging pile body, and a diagnostic module and a charging module respectively connected to the main control board. The diagnostic module includes: The main control unit includes a communication unit, which is communicatively connected to the main control board via the communication unit. An excitation signal generation module includes an adjustable sine wave generator, which is used to generate a sinusoidal AC signal; The response signal processing module includes an impedance transformation unit and an amplitude-frequency and phase-frequency characteristic testing unit. The impedance transformation unit is used to condition the response signal returned by the target battery, and the amplitude-frequency and phase-frequency characteristic testing unit is used to acquire the conditioned response signal. A power supply module, which provides DC power to the diagnostic module; A switching switch is used to control the connection between the diagnostic module and the charging gun; A DC blocking capacitor is disposed at the output terminal of the diagnostic module, and the DC blocking capacitor is used to isolate DC power. The charging module includes a trickle charging submodule, which is communicatively connected to the main control board. The output terminal of the charging module is equipped with an LC filter circuit, which is used to suppress AC excitation signals and prevent AC excitation signals from interfering with trickle charging.

2. The charging pile according to claim 1, characterized in that, The excitation signal generation module also includes a programmable frequency selection network, which is used to filter and set the frequency point of the sinusoidal AC signal generated by the adjustable sine wave generator.

3. The charging pile according to claim 1, characterized in that, The charging guns are provided in multiple ways. The number of ports of the switching switch is the same as the number of charging guns and corresponds one-to-one with each charging gun. The number of charging modules is the same as the number of charging guns and corresponds one-to-one with each charging gun.

4. The charging pile according to claim 3, characterized in that, The diagnostic module is connected in parallel with each of the charging modules, and each charging module is provided with a DC contact switch between itself and the corresponding charging gun to control the connection and disconnection between the charging module and the charging gun.

5. The charging pile according to claim 1, characterized in that, The charging pile uses PLC communication.

6. The charging pile according to any one of claims 1 to 5, characterized in that, The charging station also includes: A controller is used to control the connection or disconnection of the diagnostic module and the charging gun, and to control the connection or disconnection of the charging module and the charging gun.

7. A charging system integrating power battery diagnostic functions, characterized in that, include: The charging pile according to any one of claims 1 to 6; The main control board communicates with the battery management module via a communication module to upload the raw frequency response data collected by the diagnostic module to the battery management module, and diagnoses the status of the target battery through the battery management module.

8. The charging system according to claim 7, characterized in that, The battery management module includes: A battery big data storage unit is used to store historical charging data of the target battery. The battery diagnostic model storage unit diagnoses the state of the target battery based on the historical charging data, the raw frequency response data obtained by the diagnostic module, and the battery diagnostic model.

9. The charging system according to claim 7, characterized in that, The communication module is a 4G communication module.

10. The charging system according to claim 7, characterized in that, The battery management module is an on-board battery management module.

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