Charger load box guiding voltage generation method and guiding circuit

Abstract

The invention discloses a charger load box guiding voltage generation method and a guiding circuit. The method comprises the following steps: in an insulation detection stage of the charger, controlling a single-pole double-throw relay in a relay control module to access an electrolytic capacitor to a direct-current positive electrode path and a direct-current negative electrode path of the charger for charging; after insulation detection of the charger is completed, switching of the single-pole double-throw relay is controlled, an electrolytic capacitor is connected to a voltage detection loop, voltage detection is carried out on the charger, and the electrolytic capacitor is used for maintaining stable output of voltage detection through stored charges. According to the invention, the technical problems of low stability and poor flexibility in a voltage detection stage in charging pile metrological verification in the prior art are solved.

Description

Technical Field

[0001] This invention relates to the field of charging pile technology, and more specifically, to a method and circuit for generating a guide voltage for a charger load box. Background Technology

[0002] In the booming development of the new energy vehicle industry, electric vehicle charging piles, as a key component of infrastructure, have their metering accuracy and reliability directly affecting user rights and grid security. To ensure accurate metering of charging piles, related technologies often employ external AC power supplies to generate stable detection voltages via AC-DC conversion modules, or use programmable resistor arrays combined with constant current sources to simulate vehicle interface voltages during the voltage detection phase. However, these methods have significant technical problems and limitations, particularly regarding stability and flexibility during the voltage detection phase.

[0003] First, solutions relying on AC-DC conversion modules are limited by the stability of the external power supply and the accuracy of the conversion circuit. If the AC-DC module's voltage regulation performance is poor, the generated DC voltage is prone to exceeding tolerances, leading to charger detection failure and affecting the overall accuracy and reliability of the verification. Furthermore, the complex hardware circuitry, large and heavy equipment, and the high cost of high-precision voltage regulator modules all increase the manufacturing and maintenance costs of the verification device. Second, while programmable resistor arrays can adapt to voltage variations under different charging standards, the characteristic of their resistance changing with time and temperature can lead to accumulated voltage detection errors after long-term operation, exceeding the ±5% range allowed by national standards. This not only reduces the accuracy of the verification but may also pose a potential threat to the safety of the charger and electric vehicle. In summary, related technologies suffer from low stability and poor flexibility in the voltage detection stage of charging pile metering verification.

[0004] There is currently no effective solution to the above problems. Summary of the Invention

[0005] This invention provides a method and circuit for generating a guide voltage for a charger load box, which at least solves the technical problems of low stability and poor flexibility in the voltage detection stage of charging pile metering verification in related technologies.

[0006] According to one aspect of the present invention, a method for generating a load box pilot voltage for a charger is provided, comprising: during the insulation detection phase of the charger, controlling a single-pole double-throw relay in a relay control module to connect an electrolytic capacitor to the DC positive and DC negative paths of the charger for charging; after the insulation detection of the charger is completed, controlling the single-pole double-throw relay to switch and connect the electrolytic capacitor to a voltage detection circuit to perform voltage detection on the charger, wherein the electrolytic capacitor is used to maintain a stable output of the voltage detection using the stored charge.

[0007] According to another aspect of the present invention, a guide circuit for a charger load box is also provided, which is applied to any of the above-described charger load box guide voltage generation methods. The guide circuit includes: an electrolytic capacitor for charging during the insulation detection phase of the charger; and a relay control module including a single-pole double-throw relay for switching the connection path of the electrolytic capacitor between the insulation detection phase and the voltage detection phase.

[0008] According to another aspect of the present invention, a non-volatile storage medium is also provided, which stores a plurality of instructions adapted for a charger load box boot voltage generation method, any one of which is loaded by a processor and executed.

[0009] According to another aspect of the present invention, an electronic device is also provided, including one or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to implement any one of the charger load box boot voltage generation methods.

[0010] According to another aspect of the present invention, a computer program product is also provided, including a computer program that, when executed by a processor, implements the steps of any of the charger load box boot voltage generation methods.

[0011] In this embodiment of the invention, during the insulation detection phase of the charger, a single-pole double-throw relay in the relay control module is used to connect the electrolytic capacitor to the DC positive and DC negative paths of the charger for charging. After the insulation detection of the charger is completed, the single-pole double-throw relay is switched to connect the electrolytic capacitor to the voltage detection circuit for voltage detection of the charger. The electrolytic capacitor is used to maintain a stable output of the voltage detection using its stored charge. This achieves the goal of charging the electrolytic capacitor using the voltage output by the charger itself during the insulation detection phase, and then connecting the electrolytic capacitor as a stable voltage source to the voltage detection circuit during the charging preparation phase. This allows for charger voltage detection without relying on an external power source, thereby achieving accurate and reliable voltage detection of chargers with different charging voltage ranges without relying on an external power source. This improves the stability and flexibility of charging pile metrological verification, and solves the technical problems of low stability and poor flexibility in the voltage detection phase of charging pile metrological verification in related technologies. Attached Figure Description

[0012] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a flowchart of a method for generating a charger load box pilot voltage according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the guiding circuit of the charger load box according to an embodiment of the present invention; Figure 3 This is a flowchart of an optional method for generating the pilot voltage of a charger load box according to an embodiment of the present invention; Figure 4 This is an optional guide circuit schematic diagram according to an embodiment of the present invention; Figure 5 This is a schematic diagram of a charger load box guiding voltage generation device according to an embodiment of the present invention. Detailed Implementation

[0013] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0014] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0015] According to an embodiment of the present invention, a method for generating a charger load box pilot voltage is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0016] Figure 1 This is a flowchart of a method for generating a charger load box pilot voltage according to an embodiment of the present invention, such as... Figure 1 As shown, the method includes the following steps: In step S102, during the insulation detection stage of the charger, the single-pole double-throw relay in the control relay module connects the electrolytic capacitor to the DC positive and DC negative paths of the charger for charging. Optionally, the execution entity for steps S102 to S104 can be the main control chip. During the process of the charger starting up and inserting the vehicle interface, the charger needs to perform an insulation test to ensure that there is no risk of short circuit between the charging line and the ground. At this stage, through the single-pole double-throw relay (DPDT relay) in the relay control module, the relay contacts are switched to the position connected to the electrolytic capacitor, so that the electrolytic capacitor can be directly connected to the DC positive (DC+) and DC negative (DC-) paths output by the charger. At this time, the voltage output by the charger will charge the electrolytic capacitor to the maximum allowable charging voltage of the charger. This operation does not require an additional AC-DC converter or other external power supply, and is completed entirely using the voltage output of the charger itself.

[0017] Step S104: After completing the insulation test of the charger, control the single-pole double-throw relay to switch and connect the electrolytic capacitor to the voltage detection circuit to perform voltage detection on the charger. The electrolytic capacitor is used to maintain a stable output of voltage detection by utilizing the stored charge.

[0018] Optionally, once the insulation test is successfully completed, indicating that the connection between the vehicle interface and the charger is safe and reliable, the next testing process—the voltage detection stage—needs to proceed. In this stage, the main control chip instructs the contacts of the single-pole double-throw relay to switch to the other end, connecting the fully charged electrolytic capacitor into the voltage detection circuit. At this time, the stored charge in the electrolytic capacitor acts as a voltage source, comparing the actual output voltage of the charger with the voltage expected by the vehicle's Battery Management System (BMS), ensuring their consistency and verifying whether the charger's voltage output meets the standard. During voltage detection, the charge stored in the electrolytic capacitor provides the stable voltage required for the detection stage. Because electrolytic capacitors have a large capacitance and low equivalent series resistance (ESR), they can effectively suppress voltage fluctuations caused by transient current changes in the circuit, ensuring stable voltage output during detection. Thus, even if there are slight fluctuations in communication or operation between the charger and the vehicle's BMS during the detection process, the electrolytic capacitor can maintain a stable voltage level, allowing the voltage detection to proceed smoothly and obtain accurate results.

[0019] In this embodiment, by utilizing the energy storage characteristics of the electrolytic capacitor and the flexible switching of the relay, not only can the dependence on the AC-DC conversion module in related technologies be overcome, simplifying circuit design, but also the accuracy and adaptability of voltage detection can be improved. In other words, through steps S102 to S108, the electrolytic capacitor can be charged using the voltage output by the charger itself during the insulation detection stage, and then connected to the voltage detection circuit as a stable voltage source during the charging preparation stage. This achieves the goal of charger voltage detection without relying on an external power source, thereby enabling accurate and reliable voltage detection of chargers with different charging voltage ranges without external power supply. This improves the stability and flexibility of charging pile metering verification, thus solving the technical problems of low stability and poor flexibility in the voltage detection stage of charging pile metering verification in related technologies.

[0020] In one optional embodiment, after completing the insulation test of the charger, the single-pole double-throw relay is switched to connect the electrolytic capacitor to the voltage detection circuit to perform voltage detection on the charger. This includes: after completing the insulation test of the charger, detecting whether the electrolytic capacitor is charged to a preset maximum allowable voltage; and if the electrolytic capacitor is charged to the preset maximum allowable voltage, controlling the single-pole double-throw relay to switch to connect the electrolytic capacitor to the voltage detection circuit.

[0021] Optionally, once the charger passes the insulation test and confirms there is no risk of a short circuit to ground in the charging circuit, the next stage is to check whether the electrolytic capacitor has been successfully charged to the preset maximum allowable voltage. This detection process is crucial because the electrolytic capacitor must reach a sufficient voltage to function as a valid voltage source during the voltage detection stage. If the capacitor's voltage is lower than the preset maximum allowable voltage, it may not provide a stable voltage output in the subsequent voltage detection stage, leading to unreliable detection results. Real-time monitoring of the voltage across the electrolytic capacitor using the main control chip's voltage sampling module ensures that the capacitor has reached the necessary voltage level before proceeding to the next step. Once the voltage of the electrolytic capacitor is detected to have reached the preset maximum allowable voltage, the main control chip will immediately issue a command to control the single-pole double-throw relay to perform a switching operation. At this time, the relay contacts will switch from the charger's output path to the voltage detection circuit, connecting the electrolytic capacitor to the circuit in the voltage detection stage. The charge stored in the electrolytic capacitor will serve as a stable voltage source for voltage detection during this stage. During this process, the voltage output of the electrolytic capacitor will be used by the charger for real-time voltage comparison to verify whether the charger's voltage output meets the standard requirements, thereby achieving accurate testing of the charger's metering performance.

[0022] By employing the above methods, it can be ensured that the electrolytic capacitor has reached and can maintain the preset voltage level during the voltage detection stage. This not only improves the accuracy of voltage detection but also enhances the stability and safety of the entire guiding voltage generation method. In practical applications, this control mechanism can effectively avoid misjudgments caused by insufficient electrolytic capacitor voltage, and has a significant effect on optimizing the metrological verification process of new chargers.

[0023] In an optional embodiment, the method further includes: controlling the analog-to-digital conversion module to acquire the current voltage value of the electrolytic capacitor; comparing the current voltage value with a preset target voltage value to obtain a comparison result; and correcting the current voltage value of the electrolytic capacitor if the comparison result indicates that the deviation between the current voltage value and the preset target voltage value exceeds a preset deviation range.

[0024] Optionally, an analog-to-digital converter (ADC) is responsible for acquiring the voltage information across the electrolytic capacitor in real time. The ADC converts the acquired analog voltage signal into a digital signal, facilitating processing and analysis by the main control chip. This process continues throughout the entire pilot voltage generation method, ensuring that any minute changes in the electrolytic capacitor voltage are captured. After receiving the current voltage value of the electrolytic capacitor from the ADC, the main control chip compares it with a preset target voltage value. The preset target voltage value refers to the voltage level that the charger should maintain during voltage detection. By comparing the values, it can be determined whether the actual voltage of the electrolytic capacitor accurately reflects the target voltage or whether there is any deviation. If the comparison shows that the deviation between the current voltage value of the electrolytic capacitor and the preset target voltage value exceeds the preset allowable deviation range, the main control chip will initiate a correction procedure. Correction methods may include, but are not limited to, adjusting the charger's output voltage to recharge the electrolytic capacitor until its voltage approaches the target value; or introducing additional voltage-regulating components, such as adjustable resistors or voltage feedback circuits, into the voltage detection circuit to finely adjust the electrolytic capacitor's discharge current, thereby controlling the electrolytic capacitor's voltage output and bringing it back to the expected voltage range. This closed-loop control mechanism ensures that the electrolytic capacitor provides a highly accurate and stable voltage output during the voltage detection phase, even under the influence of external environmental factors or minor fluctuations in the circuit, achieving the ±5% voltage detection error range required by national standards through real-time correction. This mechanism can significantly improve the reliability and accuracy of charger metrological verification.

[0025] In one optional embodiment, when the comparison result indicates that the deviation between the current voltage value and the preset target voltage value exceeds a preset deviation range, the current voltage value of the electrolytic capacitor is corrected, including: adjusting the charging and discharging state of the electrolytic capacitor so that the deviation between the corrected voltage value of the electrolytic capacitor and the preset target voltage value is within the preset deviation range; or controlling the adjustment of the resistance value of the target resistor so that the deviation between the corrected voltage value of the electrolytic capacitor and the preset target voltage value is within the preset deviation range.

[0026] Optionally, when the main control chip detects that the current voltage value of the electrolytic capacitor deviates from the preset target voltage value, and this deviation exceeds the preset allowable deviation range, it will automatically adjust the charging and discharging state of the electrolytic capacitor to correct its voltage. Specifically, if the current voltage is lower than the preset target voltage, the relay can be controlled to reconnect the electrolytic capacitor to the DC path of the charger for recharging until its voltage is close to the target value. Conversely, if the voltage of the electrolytic capacitor is higher than the target value, the resistance value in the discharge circuit can be increased, or the connection time between the electrolytic capacitor and the discharge circuit can be controlled, to reduce the stored charge and thus lower the voltage to the target range.

[0027] Another voltage correction strategy involves dynamically adjusting the value of a target resistor to control the voltage of the electrolytic capacitor. The target resistor, connected between the electrolytic capacitor and the voltage sensing circuit, alters the capacitor's discharge rate. The key to this strategy is that when the capacitor's current voltage is higher than the target value, the target resistor is decreased, increasing the discharge current and accelerating the voltage drop, bringing it closer to the target voltage more quickly. Conversely, when the capacitor's voltage is lower than the target value, the target resistor is increased, slowing the discharge rate. This may necessitate a recharging process to slowly raise the capacitor's voltage until the target value is reached.

[0028] Through the two refined voltage correction strategies described above, the method in this embodiment can ensure timely adjustment even when the voltage of the electrolytic capacitor is affected by external factors or internal changes. This keeps the voltage provided by the electrolytic capacitor stable within the allowable error range of the preset target voltage value, thereby guaranteeing the accuracy and reliability of voltage detection. This closed-loop control mechanism not only improves the automation level of the equipment but also enhances the adaptability of the entire guiding voltage generation method under different environmental conditions, providing a more efficient and accurate solution for charger metrological verification.

[0029] According to an embodiment of the present invention, a guiding circuit embodiment for a charger load box is also provided. Figure 2 This is a schematic diagram of the guiding circuit of the charger load box according to an embodiment of the present invention, as shown below. Figure 2 As shown, the guiding circuit can be applied to any of the above-mentioned charger load box guiding voltage generation methods. The guiding circuit includes: an electrolytic capacitor for charging during the insulation detection phase of the charger; and a relay control module, including a single-pole double-throw relay for switching the connection path of the electrolytic capacitor between the insulation detection phase and the voltage detection phase.

[0030] Optionally, the electrolytic capacitor is the core energy storage component in this guiding circuit. It is charged to the maximum permissible voltage during the insulation detection phase of the charger. The selection of the electrolytic capacitor must consider its high withstand voltage and low internal resistance characteristics to ensure that it can withstand the high-voltage DC output of the charger and stably provide the required voltage output during the voltage detection phase. For example, a high-voltage, low-internal-resistance aluminum electrolytic capacitor can be selected. The capacitance of the electrolytic capacitor needs to be calculated based on the permissible voltage drop rate during the voltage detection phase of the charger to ensure that the electrolytic capacitor can maintain the voltage drop within the permissible range (≤5%) within 1000ms during the detection phase, thereby meeting the relevant standard requirements. The relay control module is the key component in the circuit responsible for switching the connection path of the electrolytic capacitor. Its core is a single-pole double-throw relay (DPDT relay). During the insulation detection phase of the charger, the relay connects the electrolytic capacitor to the DC positive (DC+) and DC negative (DC-) paths of the charger for charging. Once the insulation detection is completed, the relay switches the electrolytic capacitor to the voltage detection circuit according to the instructions of the main control chip, and starts the voltage detection process. This switching mechanism allows the electrolytic capacitor to flexibly switch its function between different stages, serving as both an energy storage unit during the charging process and a voltage source during the voltage detection stage, thus achieving a highly efficient detection solution without the need for an external AC-DC conversion module.

[0031] In the guiding circuit of this embodiment, a novel, low-cost, and high-precision voltage detection method is provided for the metrological verification of chargers through the ingenious combination of electrolytic capacitors and relay control modules. The electrolytic capacitor, as an energy storage unit, can be efficiently charged during the insulation detection stage. In the subsequent voltage detection stage, through relay switching, the electrolytic capacitor transforms into a voltage source for the voltage detection circuit, utilizing its stored charge for voltage comparison to ensure the accuracy of the charger's output voltage. The dynamic switching capability of the relay control module allows the entire circuit to adapt to changes in the charger's maximum charging voltage, covering the detection requirements under different charging standards without additional hardware support, greatly improving the flexibility and efficiency of the detection process.

[0032] In one alternative embodiment, the electrolytic capacitor includes a plurality of aluminum electrolytic capacitors connected in series, wherein each aluminum electrolytic capacitor has a voltage rating of at least 1200V.

[0033] Optionally, in actual circuit design, electrolytic capacitors are connected in series to improve the overall voltage withstand capability of the circuit. This is because the voltage withstand value of a single electrolytic capacitor is often limited. By connecting multiple electrolytic capacitors in series, each capacitor only needs to withstand a portion of the total voltage, thus allowing the circuit to handle higher voltages. The number and specific parameters of the series capacitors need to be determined based on the charger's maximum charging voltage range and the circuit design requirements. For example, if the charger's maximum charging voltage is 1000V and the voltage withstand value of a single electrolytic capacitor is 1200V, then a small number of high-voltage capacitors can be connected in series to meet the requirements while maintaining circuit simplicity. Setting the electrolytic capacitors to high-voltage aluminum electrolytic capacitors with a voltage withstand value of at least 1200V is to cope with various high-voltage output situations that the charger may encounter, ensuring that the capacitors are not damaged by excessive voltage during charging and discharging. Currently, with the development of electric vehicle charging technology, the maximum charging voltage of new chargers has reached or even exceeded 1000V. Therefore, it is essential to select capacitors with a voltage rating of 1200V to ensure that the capacitors can operate stably in all types of chargers and provide a reliable voltage source during the voltage detection phase.

[0034] By using multiple high-voltage aluminum electrolytic capacitors connected in series, the guiding circuit in this embodiment can not only flexibly adapt to the maximum charging voltage requirements of different charger models, but also provide stable and highly accurate voltage detection services while ensuring safety. The series connection expands the circuit's voltage withstand range, allowing it to operate normally without failure even with chargers boasting output voltages of 1000V or higher. Simultaneously, the selection of high-voltage capacitors ensures the circuit's durability and reliability under harsh operating conditions, reducing maintenance costs and potential safety hazards, and providing a solid hardware foundation for charger metrological verification.

[0035] In one alternative embodiment, the guiding circuit further includes an analog-to-digital conversion module for real-time monitoring of the voltage of the electrolytic capacitor.

[0036] Optionally, the analog-to-digital converter (ADC) module is a key component in the circuit used to convert analog signals into digital signals. In this embodiment, it is mainly responsible for real-time monitoring of the voltage across the electrolytic capacitor. Since the voltage of the electrolytic capacitor changes dynamically during the charging and discharging process, the real-time monitoring function of the ADC module ensures that the main control chip can acquire the voltage data of the electrolytic capacitor in a timely manner, which is crucial for subsequent voltage comparison and correction operations. The ADC module can continuously read the voltage of the electrolytic capacitor and convert it into a digital signal for processing by the main control chip. Through real-time monitoring, any changes in the voltage of the electrolytic capacitor can be detected promptly, including voltage increases during charging and voltage drops during the voltage detection phase. The voltage data provided by the ADC module serves as control feedback to drive the voltage comparison and correction process in the aforementioned embodiment. If the deviation between the monitored voltage and the preset target voltage exceeds the allowable range, a correction mechanism will be activated to adjust the charging and discharging state of the electrolytic capacitor or the resistance value of the target resistor to ensure that the voltage provided by the electrolytic capacitor is stable and accurate.

[0037] The analog-to-digital converter (ADC) module is tightly integrated with other components of the pilot circuit, such as the electrolytic capacitor and relay control module, forming a complete closed-loop control system. In this system, the ADC module not only provides voltage monitoring data but also works collaboratively with the main control chip, relays, and electrolytic capacitors to achieve dynamic voltage control and stable output. This integrated design ensures that the entire pilot circuit can efficiently and accurately perform the charger's metrological verification, providing the necessary data support and control feedback during both the charger's insulation testing phase and the critical voltage detection phase.

[0038] By integrating an analog-to-digital converter (ADC) module into the guiding circuit, this embodiment enables real-time monitoring and closed-loop control of the electrolytic capacitor voltage. This not only enhances the automation level of the circuit but also improves the accuracy and reliability of voltage detection. As a key component for data acquisition and control feedback, the ADC module provides technical support for precise management of the electrolytic capacitor voltage during the charger's metrological verification process, ensuring that the testing process meets relevant standards. Simultaneously, it optimizes the hardware architecture and reduces overall costs.

[0039] In an optional embodiment, the relay control module further includes a DC relay for connecting a 100-ohm (R) resistor and a 60-kilo-ohm (K) resistor during the voltage detection phase to assist in detecting the voltage comparison between the charger and the vehicle battery management system.

[0040] Optionally, to enhance the accuracy and flexibility of the voltage detection stage, a DC relay is additionally included in the guiding circuit of this embodiment. During the voltage detection stage, this DC relay is used to connect resistors of different resistance values ​​(such as 100R and 60K resistors). These resistors play an auxiliary role in the circuit, helping to detect the voltage comparison between the charger and the vehicle's Battery Management System (BMS). During the voltage comparison between the charger and the vehicle's BMS, connecting resistors of different resistance values ​​via the DC relay can simulate the electrical characteristics of the vehicle's battery interface. The selection and connection of the 100R and 60K resistors depend on the circuit design requirements and specific application scenarios. For example, a 100R resistor might be used to simulate voltage detection under low impedance conditions, while a 60K resistor might be used to simulate voltage detection under high impedance conditions. By switching the connection of these resistors, the relay control module can provide a wider range of voltage detection conditions, thereby ensuring that the charger's voltage detection function operates normally under various possible vehicle interface impedances and meets the ±5% voltage detection error requirements of relevant standards.

[0041] Specifically, during the voltage detection phase, the main control chip, based on the acquired electrolytic capacitor voltage value and the specific communication requirements between the charger and the vehicle's BMS, selectively connects a 100R or 60K resistor to the detection circuit by controlling the switching of DC relay contacts. This process may rely on real-time voltage data monitored by the analog-to-digital converter module and feedback information from the vehicle's BMS obtained through the communication interface. In this way, the detection conditions can be adaptively adjusted to ensure accurate voltage comparison under various circumstances.

[0042] By including a DC relay in the relay control module, additional control functions can be provided to the guide circuit of the charger load box, making the operation during the voltage detection stage more flexible and precise. By connecting resistors of different values, this relay can simulate the electrical characteristics of various vehicle battery interfaces, thereby ensuring the accuracy of the charger's detection results when comparing voltages with different vehicles.

[0043] With the rapid growth of new energy vehicles, the demand for electric vehicle charging stations has also increased dramatically. Many cities have installed a large number of public and private charging stations. Therefore, verifying the metrological performance of electric vehicle charging stations has become an urgent issue closely related to people's lives. As a new and comprehensive industry, charging stations present many new requirements for metrological verification work. Implementing metrological verification for charging stations, improving the metrological verification guarantee for the entire charging station industry, and organically integrating metrological verification with the charging station industry are essential. Therefore, enforcing mandatory metrological verification for electric vehicle charging stations to ensure the accuracy of their metrological performance is crucial. According to relevant standards (such as national standard GB / T 18487.1), the charger must complete the power supply circuit voltage detection before outputting DC voltage: It obtains the real-time voltage value of the vehicle interface (provided by the vehicle's BMS) through communication messages and compares it with the actual voltage value detected by itself. If the error is ≤ ±5% and the voltage is within the charger's minimum (e.g., 200V) and maximum (e.g., 750V) charging voltage range, the voltage is considered normal, and the DC power supply circuit is activated. This mechanism is the core link to ensure electrical compatibility between the charger and the vehicle and to avoid overvoltage / undervoltage damage. Conventional calibration devices often use an "external AC power supply + AC-DC conversion" scheme: AC power (e.g., 220V / 380V) is rectified, filtered, and regulated to a stable DC voltage, directly simulating the vehicle interface voltage for charger detection. Another scheme is a "programmable resistor array + main control dynamic adjustment" guide circuit: the main control chip controls a multi-channel switch to switch the equivalent resistance value of the resistor array, combined with a low-power constant current source to generate the target detection voltage. Its advantage lies in the fact that it does not require an external AC power source and can flexibly adapt to different charging standards; however, the above-mentioned technologies have the following problems: 1) Using an AD-DC converter for boost voltage guidance relies on an external power supply. If the AC-DC conversion module's voltage regulation capability is insufficient, the converted DC voltage may exceed tolerances, causing the charger to fail the test. Furthermore, the hardware circuit's boost voltage value cannot be arbitrarily changed, failing to meet the needs of usage scenarios where the maximum charging voltage frequently changes. For example, the maximum charging voltage of current mainstream chargers is 750V, while newer chargers have reached 1000V.

[0044] 2) AD-DC circuits require the integration of multiple stages such as rectification, filtering, and voltage regulation, resulting in high hardware circuit complexity. Furthermore, high-precision voltage regulator modules are expensive, significantly increasing the overall cost.

[0045] 3) Programmable resistor arrays typically use multiple precision resistors switched by multiplexers to achieve equivalent adjustment, enabling matching of scenarios with variations in the highest charging voltage. However, the actual resistance value is affected by temperature and aging, and the cumulative error over long-term use may exceed ±5% of relevant standards (such as national standards). The specific problems with the above-mentioned technologies are as follows: 1) In related technologies, the calibration devices rely on external AC power to generate a test voltage via AC-DC conversion. The boost voltage is fixed by hardware circuitry (such as rectifier, filter, and voltage regulator modules) and cannot be flexibly adjusted. However, with the upgrading of charger technology, the mainstream maximum charging voltage has increased from 750V to 1000V, and may further increase in the future. Traditional solutions, due to their non-adjustable boost voltage, cannot meet the high-voltage testing requirements of new chargers. Furthermore, if the AC-DC conversion module's voltage regulation capability is insufficient, the converted DC voltage is prone to exceeding tolerances, leading to charger test failure and affecting calibration accuracy.

[0046] 2) The AC-DC conversion scheme in related technologies needs to integrate multiple complex components such as rectification, filtering, and voltage regulation (e.g., diode rectifier bridge, electrolytic capacitor, and switching power supply module). The high complexity of the hardware circuit not only leads to large size and heavy weight of the equipment, but also significantly increases the overall cost of the calibration device due to the high cost of high-precision voltage regulation modules (e.g., industrial-grade switching power supplies).

[0047] 3) The programmable resistor array solution simulates the detection voltage by switching resistor combinations, but its equivalent resistance is affected by temperature drift (such as the temperature coefficient of metal film resistors is about ±50ppm / ℃) and long-term aging (resistance drifts with the use time). After long-term operation, the cumulative error may exceed ±5% of the relevant standards.

[0048] To address the aforementioned problems, based on the above embodiments and optional embodiments, the present invention proposes an optional implementation method. Figure 3 This is a flowchart of an optional charger load box pilot voltage generation method according to an embodiment of the present invention. This method is applied to, for example... Figure 2 The guiding circuit shown mainly consists of the following hardware components: 1) Electrolytic capacitors: High-voltage, low-internal-resistance aluminum electrolytic capacitors are selected. The capacitance is calculated based on the allowable voltage drop rate during the detection phase. The detection phase lasts for 1000ms, and the allowable voltage drop is ≤5%. Therefore, the capacitance C = ΔVI × t, where I is the detection circuit current, t is the detection time, and ΔV is the allowable drop value. Multiple capacitors are ultimately selected in series, with a maximum voltage rating of 1200V, which is sufficient to meet the voltage range requirements of current market testing circuits. 2) Relay control module: A single-pole double-throw relay is used to control the on / off state of the "insulation detection circuit" and the "voltage detection circuit" respectively.

[0049] Figure 4This is an optional guide circuit schematic diagram according to an embodiment of the present invention, such as... Figure 4 As shown, the guiding circuit includes: a DC gun (i.e., charger, DC Gun), which is the interface part connected to the electric vehicle. It contains a charging positive terminal (DC+) and a charging negative terminal (DC-) for providing DC power to the electric vehicle. A DC circuit breaker is used to control the on / off state of the DC power supply and provide overload and short-circuit protection, protecting the circuit from damage caused by excessive current. Relay K1 is a single-pole double-throw relay: during the insulation detection stage, K1 connects the electrolytic capacitor to the DC+ and DC- paths of the charger, charging the electrolytic capacitor to the maximum allowable charging voltage; during the voltage detection stage, K1 switches positions, connecting the electrolytic capacitor to the voltage detection circuit as a stable voltage source. DC relay K2 plays an auxiliary role in the circuit; for example, during the electrolytic capacitor pre-charging stage, K2 closes to pre-charge the electrolytic capacitor to a certain voltage, avoiding voltage surges during the voltage detection stage and ensuring detection accuracy. The voltage sampling module (A / D Conversion Module) is used to monitor the voltage of the electrolytic capacitor in real time, converting the analog voltage signal into a digital signal for processing and analysis by the main control chip, thus enabling precise control of the electrolytic capacitor voltage. Other components include: VDD indicating the positive voltage of the power supply; 1K and 100R resistors for building the basic circuit structure and protecting the circuit from sudden current changes; and CC1 and CC2 markings to check if the charging gun or vehicle interface is correctly connected, i.e., whether the plug is fully inserted, to prevent charging when not fully connected, ensuring charging safety. The power supply (DC1000V 150A) is the charger's output power, providing 1000V DC voltage and 150A current for charging electric vehicles. High-voltage electrolytic capacitors are used for energy storage; their capacity and withstand voltage are designed according to the voltage drop requirements of the detection phase to ensure a stable and standard-compliant voltage output during voltage detection.

[0050] The overall hardware schematic of the bootloader system works as follows: Charger Startup: Power supply is ready, awaiting charging instructions. Insulation Detection Phase: K1 controls the connection of the electrolytic capacitor to the charger's output path, and the electrolytic capacitor begins charging to the maximum allowable charging voltage. During this phase, the charger checks the electrical isolation status between itself and the electric vehicle. Charger Opens Discharge Circuit: After the insulation detection passes, the charger opens its internal discharge circuit to safely disconnect the charging gun from the vehicle. Simultaneously, the main control chip controls K1 to disconnect the electrolytic capacitor from the charger output. Voltage Detection Phase: K1 again controls the switch of the electrolytic capacitor to the voltage detection circuit. At this time, the electrolytic capacitor acts as a stable voltage source for voltage comparison between the charger and the vehicle's BMS, ensuring voltage consistency and accuracy. Charging Start: If the voltage detection passes, the charger begins supplying power to the electric vehicle according to the parameters confirmed in previous communication until it reaches a stop state, at which point charging ends. Through the above process, this guidance scheme can charge the electrolytic capacitor using the voltage output by the charger itself without relying on an external power source. Then, the voltage is detected using the charge stored in the electrolytic capacitor. This simplifies the complexity of the detection device in related technologies, reduces costs, and improves the flexibility and accuracy of detection.

[0051] This embodiment proposes a charger-guided voltage generation scheme based on electrolytic capacitor energy storage, based on the charging process characteristics of chargers in relevant standards (such as national standard GB / T 18487.1), especially the stage sequence of insulation detection and voltage detection. Through ingenious stage switching control, the dynamic generation of detection voltage can be achieved without an external power supply, while taking into account low cost, high accuracy, and high adaptability. Figure 3 As shown, the method includes: The charging process of the charger follows the requirements of GB / T 18487.1, and must sequentially complete the stages of "insulation detection → charging preparation → voltage detection → charging start". This embodiment utilizes this process characteristic. During the insulation detection stage, a relay connects the electrolytic capacitor to the charger's DC positive path (DC+) and DC negative path (DC-), charging the capacitor to the charger's maximum allowable charging voltage. Since the charger opens the discharge circuit after insulation detection, the main control chip controls the relay to disconnect the insulation detection circuit. During the charging preparation stage (when the power supply circuit voltage needs to be detected), the electrolytic capacitor is reconnected to the detection circuit, using its stored charge as a detection voltage source for voltage comparison between the charger and the vehicle's BMS. The entire process requires no external AC-DC conversion module; the generation and stable output of the detection voltage can be achieved solely through the on / off control of the relay and the energy storage characteristics of the electrolytic capacitor.

[0052] It should be noted that this embodiment can achieve at least one of the following effects: 1) In this embodiment, the detection voltage is directly charged to the electrolytic capacitor by the maximum charging voltage output by the charger itself, without relying on the AC-DC conversion module, completely eliminating dependence on external AC power. It can also flexibly adapt to the maximum charging voltage requirements of different charger models. 2) In related technologies, AC-DC conversion schemes require multiple components such as rectifier bridges, filter capacitors, and switching power supplies. This embodiment only requires electrolytic capacitors, relays, and simple control circuits, reducing hardware complexity by more than 60% and eliminating the high cost of high-precision voltage regulator modules. 3) The voltage drop of the electrolytic capacitor is mainly caused by self-discharge. In this embodiment, by selecting low-leakage-current electrolytic capacitors and limiting the detection stage time, the voltage drop can be controlled within ±2%; combined with real-time sampling calibration of the main control chip, the final detection error can be stably controlled within ±5%.

[0053] This embodiment also provides a charger load box guide voltage generation device, which is used to implement the above embodiments and preferred embodiments, and will not be repeated as already described. As used below, the terms "module" and "device" can refer to a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0054] According to an embodiment of the present invention, an apparatus embodiment for implementing the above-described charger load box pilot voltage generation method is also provided. Figure 5 This is a schematic diagram of a charger load box guiding voltage generation device according to an embodiment of the present invention, as shown below. Figure 5 As shown, the above-mentioned charger load box guiding voltage generation device includes: an electrolytic capacitor charging control module 500 and a voltage detection module 502, wherein: The electrolytic capacitor charging control module 500 is used to control the single-pole double-throw relay in the relay control module to connect the electrolytic capacitor to the DC positive and DC negative paths of the charger for charging during the insulation detection stage of the charger. The voltage detection module 502 is connected to the electrolytic capacitor charging control module 500. After completing the insulation test of the charger, it controls the single-pole double-throw relay to switch and connect the electrolytic capacitor to the voltage detection circuit to perform voltage detection on the charger. The electrolytic capacitor is used to maintain a stable output of voltage detection by utilizing the stored charge.

[0055] It should be noted that the above modules can be implemented by software or hardware. For example, for the latter, it can be implemented in the following ways: the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0056] It should be noted that the electrolytic capacitor charging control module 500 and voltage detection module 502 mentioned above correspond to steps S102 to S104 in the embodiments. The examples and application scenarios implemented by the above modules and corresponding steps are the same, but are not limited to the content disclosed in the above embodiments. It should be noted that the above modules, as part of the device, can run in a computer terminal.

[0057] It should be noted that the optional or preferred implementation methods of this embodiment can be found in the relevant descriptions in the embodiments, and will not be repeated here.

[0058] The aforementioned charger load box guiding voltage generation device may also include a processor and a memory. The aforementioned electrolytic capacitor charging control module 500, voltage detection module 502, etc., are all stored in the memory as program modules, and the processor executes the aforementioned program modules stored in the memory to realize the corresponding functions.

[0059] The processor contains a core that retrieves the corresponding program modules from memory. One or more cores may be configured. Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory includes at least one memory chip.

[0060] According to an embodiment of this application, an embodiment of a non-volatile storage medium is also provided. Optionally, in this embodiment, the non-volatile storage medium includes a stored program, wherein, when the program runs, it controls the device containing the non-volatile storage medium to execute any of the charger load box boot voltage generation methods.

[0061] Optionally, in this embodiment, the non-volatile storage medium may be located in any computer terminal in a group of computer terminals in a computer network, or in any mobile terminal in a group of mobile terminals, and the non-volatile storage medium includes stored programs.

[0062] Optionally, a program may be used to control the device containing the non-volatile storage medium to execute any of the above-described steps of the charger load box boot voltage generation method during program execution.

[0063] According to an embodiment of this application, an embodiment of a processor is also provided. Optionally, in this embodiment, the processor is used to run a program, wherein the program executes any of the above-described charger load box boot voltage generation methods.

[0064] According to an embodiment of this application, an embodiment of a computer program product is also provided, which, when executed on a data processing device, is adapted to execute a program that initializes the charger load box boot voltage generation method steps described above.

[0065] This invention provides an electronic device, which includes a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps of the charger load box boot voltage generation method described above.

[0066] The order of the above embodiments of the present invention is merely for description and does not represent the superiority or inferiority of the embodiments.

[0067] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0068] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of modules described above can be a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, or indirect coupling or communication connection between modules, and may be electrical or other forms.

[0069] The modules described above as separate components may or may not be physically separate. Similarly, the components shown as modules may or may not be physical modules; they may be located in one place or distributed across multiple modules. Some or all of the modules can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0070] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The integrated modules described above can be implemented in hardware or as software functional modules.

[0071] If the aforementioned integrated modules are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable non-volatile storage medium. Based on this understanding, the technical solution of this invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a non-volatile storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned non-volatile storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0072] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for generating a pilot voltage for a charger load box, characterized in that, include: During the insulation detection phase of the charger, the single-pole double-throw relay in the control relay module connects the electrolytic capacitor to the DC positive and DC negative paths of the charger for charging. After completing the insulation test of the charger, the single-pole double-throw relay is switched to connect the electrolytic capacitor to the voltage detection circuit to perform voltage detection on the charger. The electrolytic capacitor is used to maintain a stable output of the voltage detection using the stored charge.

2. The method according to claim 1, characterized in that, After completing the insulation test on the charger, the step of controlling the single-pole double-throw relay to switch and connect the electrolytic capacitor to the voltage detection circuit to perform voltage detection on the charger includes: After completing the insulation test on the charger, check whether the electrolytic capacitor is charged to the preset maximum allowable voltage; When the electrolytic capacitor is charged to the preset maximum allowable voltage, the single-pole double-throw relay is switched to connect the electrolytic capacitor to the voltage detection circuit.

3. The method according to claim 1, characterized in that, The method further includes: The analog-to-digital converter module is controlled to acquire the current voltage value of the electrolytic capacitor; The current voltage value is compared with the preset target voltage value to obtain the comparison result; If the comparison result indicates that the deviation between the current voltage value and the preset target voltage value exceeds a preset deviation range, the current voltage value of the electrolytic capacitor is corrected.

4. The method according to claim 3, characterized in that, When the comparison result indicates that the deviation between the current voltage value and the preset target voltage value exceeds a preset deviation range, the current voltage value of the electrolytic capacitor is corrected, including: If the comparison result indicates that the deviation between the current voltage value and the preset target voltage value exceeds the preset deviation range, the charging and discharging state of the electrolytic capacitor is adjusted so that the deviation between the corrected voltage value of the electrolytic capacitor and the preset target voltage value is within the preset deviation range; or If the comparison result indicates that the deviation between the current voltage value and the preset target voltage value exceeds the preset deviation range, the resistance value of the target resistor is adjusted so that the deviation between the corrected voltage value of the electrolytic capacitor and the preset target voltage value is within the preset deviation range.

5. A guiding circuit for a charger load box, characterized in that, The method for generating a pilot voltage for a charger load box according to any one of claims 1 to 4, wherein the pilot circuit comprises: Electrolytic capacitors are used for charging during the insulation testing phase of the charger. The relay control module includes a single-pole double-throw relay for switching the connection path of the electrolytic capacitor between the insulation detection phase and the voltage detection phase.

6. The guiding circuit according to claim 5, characterized in that, The electrolytic capacitor includes multiple aluminum electrolytic capacitors connected in series, wherein each aluminum electrolytic capacitor has a voltage rating of at least 1200V.

7. The guiding circuit according to claim 5, characterized in that, The guiding circuit also includes an analog-to-digital conversion module for real-time monitoring of the voltage of the electrolytic capacitor.

8. The guiding circuit according to claim 5, characterized in that, The relay control module also includes a DC relay for connecting a 100-ohm resistor and a 60-kiloohm resistor during the voltage detection phase to assist in detecting the voltage comparison between the charger and the vehicle battery management system.

9. A non-volatile storage medium, characterized in that, The non-volatile storage medium stores multiple instructions adapted for loading and execution by a processor of the charger load box boot voltage generation method according to any one of claims 1 to 4.

10. An electronic device, characterized in that, It includes one or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to implement the charger load box boot voltage generation method according to any one of claims 1 to 4.

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