A method, device and system for detecting loss of continuity of a protective earthing conductor of a charging station

Abstract

The application relates to a charging pile protection ground conductor continuity loss response detection method, device and system, which comprises the following steps: cutting off all protection ground electrical paths except the protection ground conductor connected to the input end of the charging pile; connecting an external protection ground conductor breaker in series between the charging gun line of the charging pile and a simulation load device; obtaining the control guide signal of the charging pile in the steady charging working condition as a first signal waveform; switching the protection ground conductor breaker from the on state to the off state, and obtaining the control guide signal waveform of the charging pile as a second signal waveform; judging whether the second signal waveform jumps from the first signal waveform to the fault state direct current level representing the protection ground loss within the preset time threshold; and outputting the detection result of the protection ground conductor electrical continuity loss protection response of the charging pile according to the judgment result.

Description

Technical Field

[0001] This invention relates to the field of charging pile technology, specifically to a method, device, and system for detecting the continuity loss response of the protective grounding conductor of a charging pile. Background Technology

[0002] In the type testing and 3C certification of AC charging piles, the continuous loss protection test of the protective grounding conductor (PE) is a key item for verifying the safety function of the equipment. According to the requirements of Appendix A.3.10.6 of GB / T 18487.1—2023, when the protective grounding conductor between the charging pile and the vehicle is lost, the charging pile should detect the fault within a specified time and cause the control guide signal to jump from the pulse width modulation waveform to the DC level indicating the fault state of protective grounding loss, and stop the power output.

[0003] Currently, this test typically uses an AC interoperability simulation box with an integrated PE relay to simulate vehicle load, simulating PE loss by controlling the on / off state of the PE relay. However, when testing using this method, a common phenomenon occurs where the PE relay is physically disconnected, but the control guidance signal still maintains a pulse width modulation waveform and fails to transition to the DC level of the fault state. This leads to the charging pile's protection function being unable to be accurately determined, resulting in a so-called "false disconnection" misjudgment. For example, a PE line protection system for a power supply and charging device described in patent publication number CN214044996U controls a switch to cut off the PE line through a drive circuit to prevent incorrect current from flowing into the PE line and causing electric shock hazard. Although this achieves PE line on / off control, it does not consider the ground loop problem introduced by the auxiliary equipment's own grounding in the test environment. For example, an AC charging pile grounding detection and control device described in patent application CN110884380A detects grounding faults and controls the AC contactor to disconnect power through circuits such as optocouplers and rectifier bridges. This device monitors grounding continuity in real time and cuts off the output in case of a fault. However, because the PE line of the analog box power supply, the ground wire of the oscilloscope probe, and the grounding of the equipment casing in the test system are all connected to the same distribution box grounding bar as the PE line of the charging pile input, multiple additional PE bypass paths are formed. This causes the charging pile's detection circuit to still sense low-impedance connections through bypasses even after the PE relay physically disconnects, thus failing to trigger the protection action. Therefore, developing a detection method that can eliminate ground loop interference in the test environment, ensure the charging pile responds accurately after the PE is physically disconnected, and thus accurately detect the loss of protective grounding conductor continuity protection function has become a pressing technical problem in this field.

[0004] This application relates to the development of a method, apparatus, and system for detecting the continuity loss response of the protective grounding conductor of a charging pile, in order to solve the aforementioned problems. Summary of the Invention

[0005] To achieve the above-mentioned objectives and other advantages of the present invention, a method for detecting the continuity loss response of the protective grounding conductor of a charging pile according to the present invention includes the following steps: Disconnect all protective grounding electrical paths except for the protective grounding conductor connected to the input terminal of the charging pile in order to perform grounding isolation operation on auxiliary equipment in the test environment; An external protective grounding conductor cut-off device is connected in series between the charging gun line of the charging pile and the simulated load device. The control guidance signal when the charging pile enters the steady-state charging condition is obtained and used as the first signal waveform; Switch the protective grounding conductor cut-off device from the on state to the off state, and obtain the control guidance signal waveform output by the charging pile at the switching moment as the starting point, as the second signal waveform; Determine whether the second signal waveform changes from the first signal waveform to a DC level indicating a fault state of grounding loss within a preset time threshold. Based on the judgment result, the detection result of the electrical continuity loss protection response of the protective grounding conductor of the charging pile is output.

[0006] Furthermore, the auxiliary equipment includes: The power supply for the simulated load device, the oscilloscope for monitoring the control guidance signal, the simulated load device itself, and other electrical equipment with protective grounding conductors in the detection system.

[0007] Furthermore, the grounding isolation operation performed on auxiliary equipment in the test environment includes the following steps: Disconnect the protective grounding conductor of the power supply line that supplies power to the simulated load device; An isolation transformer is used to power the oscilloscope used for monitoring and controlling the guidance signals, so that the oscilloscope is in a floating measurement state; Disconnect the independent grounding wire of the housing of the simulated load device.

[0008] Furthermore, before acquiring the control guidance signal when the charging pile enters the steady-state charging condition, the following steps are also included: Measure the equivalent resistance between the internal grounding node of the simulated load device and the power distribution system ground; Determine whether the equivalent resistance is greater than a preset resistance threshold; If the equivalent resistance is greater than the preset resistance threshold, the grounding isolation operation is confirmed to be effective, and subsequent steps are allowed to proceed. If the equivalent resistance is less than or equal to the preset resistance threshold, the grounding isolation operation is confirmed to be invalid, and the investigation continues to cut off any undiscovered protective grounding electrical paths.

[0009] Furthermore, the preset resistance threshold is set to 100kΩ.

[0010] A second objective of this invention is to provide a detection device for the continuity loss response of the protective grounding conductor of a charging pile, for performing the above-described method, comprising the following: The input interface includes a live wire input terminal, a neutral wire input terminal, a protective grounding input terminal, and a control guide input terminal, which are used to connect the charging gun wire of the charging pile; The output interface includes a live wire output terminal, a neutral wire output terminal, a protective grounding output terminal, and a control guide output terminal, which are used to connect the analog load device. A signal pass-through line is used to electrically connect the input interface to the corresponding terminals of the output interface, excluding the protective grounding terminal. A protective grounding conductor cut-off device is connected in series between the protective grounding input terminal and the protective grounding output terminal to realize the physical on / off control of the protective grounding conductor.

[0011] Furthermore, the protective grounding conductor cut-off device is an external, manually operated mechanical disconnect switch.

[0012] Furthermore, the mechanical disconnect switch has a visual mechanical status indication structure and is a passive device.

[0013] Furthermore, the protective grounding conductor cut-off device is equipped with an on / off status indicator.

[0014] A third objective of this invention is to provide a detection system for the continuity loss response of the protective grounding conductor of a charging pile, comprising: The protective grounding conductor continuity loss response detection device for the charging pile, as described above, is connected in series between the charging gun line of the charging pile and the simulated load device. A control unit, used to connect to the detection device and the charging pile; wherein the control unit includes: The test environment configuration module is used to disconnect all protective grounding electrical paths except for the protective grounding conductor connected to the input terminal of the charging pile, so as to perform grounding isolation operation on the auxiliary equipment in the test environment; The signal acquisition module is used to acquire the control guidance signal when the charging pile enters the steady-state charging condition, as the first signal waveform; and to switch the protective grounding conductor cut-off device from the on state to the off state, and acquire the control guidance signal waveform output by the charging pile at the switching moment as the second signal waveform. A detection module is used to determine whether the second signal waveform changes from the first signal waveform to a DC level indicating a fault state of protective grounding loss within a preset time threshold; based on the determination result, it outputs the detection result of the electrical continuity loss protection response of the protective grounding conductor of the charging pile. A fourth objective of this invention is to provide a readable storage medium storing a computer program, characterized in that, when the computer program is executed by a processor, it implements a method for detecting the continuity loss response of the protective grounding conductor of a charging pile.

[0015] Compared with the prior art, the beneficial effects of the present invention are: This invention relates to a method, apparatus, and system for detecting the continuity loss response of the protective grounding conductor in a charging pile. By disconnecting all protective grounding electrical paths in the test environment except for the protective grounding conductor connected to the charging pile input terminal to eliminate ground loop interference, an external protective grounding conductor cut-off device is connected in series between the charging gun line and the simulated load device. After acquiring the first signal waveform under steady-state charging conditions, the cut-off device is switched from the on state to the off state, and a second signal waveform is acquired starting from the switching moment. It is then determined whether the second signal waveform jumps from the first signal waveform to the DC level indicating a fault state of protective grounding loss within a preset time threshold. This not only avoids false disconnection misjudgments caused by multiple ground loops introduced by the auxiliary equipment's own grounding, but also accurately evaluates the protection response time of the charging pile by using the manual actuation moment as the timing start point, ensuring that the test results meet the timeliness requirements specified in the standard. Simultaneously, the use of an external physical cut-off device achieves true verification isolation of the protective grounding conductor, significantly improving the accuracy and reliability of the continuous loss protection function detection of the charging pile's protective grounding conductor.

[0016] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it according to the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Specific embodiments of the present invention are given in detail below with reference to the accompanying drawings. Attached Figure Description

[0017] 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 detecting the continuity loss response of the protective grounding conductor of a charging pile according to this application; Figure 2 This is a flowchart illustrating the grounding isolation operation performed on auxiliary equipment in the test environment as described in Example 1. Figure 3This is a flowchart illustrating the verification of the effectiveness of the grounding isolation operation described in Example 1; Figure 4 This is a schematic diagram of the first signal waveform described in Example 1; Figure 5 This is a schematic diagram of the DC level when the protective grounding conductor is lost and enters a fault state as described in Example 1; Figure 6 This is a flowchart illustrating the detection results of the protection grounding conductor electrical continuity loss protection response of the charging pile, as described in Example 1, based on the judgment result. Figure 7 Wiring diagram of the protective grounding conductor continuity loss response detection device for the charging pile described in Example 2. Figure 1 ; Figure 8 Wiring diagram of the protective grounding conductor continuity loss response detection device for the charging pile described in Example 2. Figure 2 ; Figure 9 This is a schematic diagram of the protective grounding conductor continuity loss response detection device for the charging pile described in Example 2; Figure 10 This is a schematic diagram of the protective grounding conductor continuity loss response detection system for the charging pile described in Example 3. Figure 1 ; Figure 11 This is a schematic diagram of the protective grounding conductor continuity loss response detection system for the charging pile described in Example 3. Figure 2 ; Figure 12 This is a schematic diagram of a computer-readable storage medium in Example 4; In the picture: 100. Insulating housing; 210. Live wire input terminal; 220. Neutral wire input terminal; 230. Protective grounding input terminal; 240. Control guide input terminal; 310. Live wire output terminal; 320. Neutral wire output terminal; 330. Protective grounding output terminal; 340. Control guide output terminal; 500. Protective grounding conductor cut-off device. Detailed Implementation

[0018] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0019] In the following description, the use of suffixes such as "module," "part," or "unit" to denote elements is solely for the purpose of illustrative purposes and has no specific meaning in itself. Therefore, "module," "part," or "unit" may be used interchangeably.

[0020] It should be noted that, in order to clearly and accurately define the key concepts involved in this application, the following terms are defined as follows: "Protective grounding conductor" refers to a conductor used to connect the exposed conductive parts of electrical equipment to an external grounding system, and may also be referred to as "PE wire" in this application.

[0021] "Control guidance signal" refers to the signal used between the charging pile and the device to be charged to transmit charging status, control commands and confirm connection. In this application, it can also be referred to as "CP signal".

[0022] "Simulated load device" refers to auxiliary test equipment used to simulate the control and guidance circuit and charging load characteristics of electric vehicles. In this application, it may also be referred to as "simulation box" or "AC interoperability simulation box".

[0023] "Power distribution system ground" refers to the power distribution system grounding terminal block that provides a common grounding reference point in the test environment, and may also be referred to as "distribution box grounding bar" in this application.

[0024] It should be understood that the different expressions of the above terms have the same technical meaning in this application, refer to the same object, and do not cause ambiguity due to differences in naming.

[0025] Example 1 A method for detecting the continuity loss response of the protective grounding conductor of a charging pile, such as Figure 1 As shown, the specific steps include the following: S101, disconnect all protective grounding electrical paths except for the protective grounding conductor connected to the input terminal of the charging pile, in order to perform grounding isolation operation on auxiliary equipment in the test environment; S102, An external protective grounding conductor cut-off device is connected in series between the charging gun line of the charging pile and the simulated load device. S103, acquire the control guidance signal when the charging pile enters the steady-state charging condition, and use it as the first signal waveform; S104, switch the protective grounding conductor cut-off device from the on state to the off state, and obtain the control guidance signal waveform output by the charging pile as the starting point of the switching moment, as the second signal waveform; S105, determine whether the second signal waveform jumps from the first signal waveform to the DC level indicating a fault state of grounding loss within a preset time threshold; S106, based on the judgment result, output the detection result of the electrical continuity loss protection response of the protective grounding conductor of the charging pile.

[0026] In some embodiments, the auxiliary device mentioned in step S101 includes: The power supply for the simulated load device, the oscilloscope for monitoring the control guidance signal, the simulated load device itself, and other electrical equipment with protective grounding conductors in the detection system.

[0027] In some embodiments, the test environment described in step S101 includes at least: an AC charging pile under test, a simulated load device for simulating the vehicle-side control guidance circuit and load characteristics, an oscilloscope for monitoring the control guidance signal waveform, and an auxiliary power supply for powering the simulated load device. In a normal connection state, the protective grounding conductor at the input end of the charging pile is directly electrically connected to the grounding terminal block of the power distribution system. The power protective grounding conductors of the simulated load device, the oscilloscope, the independent grounding wire of the simulated load device's casing, and the protective grounding conductors of other measuring instruments in the test environment are typically also connected to the same distribution box grounding busbar. These multiple grounding connection points together constitute multiple parallel protective grounding electrical paths, any of which can serve as a current return path for the charging pile's protective grounding detection circuit.

[0028] Specifically, it should be understood that when the PE relay inside the simulated load device is physically disconnected, if any of the above-mentioned bypass paths exist, the protective grounding detection circuit of the charging pile can still form a closed loop through the following bypass: It is led out from the protective grounding conductor at the input end of the charging pile, transmitted through the protective grounding conductor in the charging gun line to the internal vehicle grounding node of the simulated load device, then transmitted through the Y capacitor of the internal switching power supply of the simulated load device or through a direct electrical connection to the protective grounding conductor of the power supply line of the simulated load device, then returned to the grounding terminal block of the power distribution system, and finally back to the protective grounding conductor at the input end of the charging pile. In addition, a similar bypass loop can also be formed through the oscilloscope probe ground clamp and the oscilloscope power supply protective grounding conductor.

[0029] In some embodiments, to eliminate the aforementioned unintended protective grounding bypass path, the grounding isolation operation performed on auxiliary equipment in the test environment as described in step S101, such as... Figure 2 As shown, the specific steps include: S1011, Disconnect the protective grounding conductor of the power supply line that supplies power to the simulated load device; S1012, an isolation transformer is used to power the oscilloscope used for monitoring and controlling the guidance signal so that the oscilloscope is in a floating measurement state; S1013, disconnect the independent grounding wire of the housing of the simulated load device.

[0030] After completing the grounding isolation operation described in step S101, all protective grounding electrical paths in the test environment except for the protective grounding conductor connected to the charging pile input terminal have been cut off. At this time, the test environment presents a single-point grounding topology, that is, there is only one grounding path formed by the protective grounding conductor in the charging pile gun line from the internal grounding node of the simulated load device to the power distribution system ground.

[0031] To further verify the effectiveness of the grounding isolation operation, before step S102, as follows: Figure 3 As shown, it also includes the following steps: S1014, Measure the equivalent resistance between the internal grounding node of the simulated load device and the power distribution system ground; S1015, determine whether the equivalent resistance is greater than a preset resistance threshold; S1016a, if the equivalent resistance is greater than the preset resistance threshold, then the grounding isolation operation is confirmed to be effective, and subsequent steps are allowed to be executed.

[0032] S1016b, if the equivalent resistance is less than or equal to the preset resistance threshold, then the grounding isolation operation is confirmed to be invalid, and the undiscovered protective grounding electrical path is investigated and cut off until the equivalent resistance is greater than the preset resistance threshold.

[0033] In a preferred embodiment, the preset resistance threshold is set to 100kΩ.

[0034] Specifically, it should be understood that in step S1016b, if the grounding isolation operation is confirmed to be ineffective, the investigation continues and undetected protective grounding electrical paths are disconnected. After each suspected path is disconnected, the process returns to step S1014 to remeasure the equivalent resistance, and the judgments in steps S1015 and S1016b are executed again until the measured equivalent resistance is greater than the preset resistance threshold. The undetected protective grounding electrical paths include, but are not limited to: protective grounding conductor connections of other measuring instruments on the test platform, accidental grounding of cable shielding layers, implicit contact between the equipment casing and the power distribution system ground, and grounding connections of the metal parts of the test bench, to verify the effectiveness of the grounding isolation operation.

[0035] Through the investigation and verification mechanism in step S101, it is ensured that there is only one grounding path in the test environment from the internal grounding node of the simulated load device through the protective grounding conductor in the charging pile gun line to the power distribution system ground, thereby laying a reliable test foundation for the accurate detection of the continuity loss protection function of the charging pile protective grounding conductor.

[0036] After performing the grounding isolation operation in step S101 and confirming that the test environment meets the single-point grounding conditions, this application connects the external protective grounding conductor cut-off device into the test circuit.

[0037] In some embodiments, the protective grounding conductor cut-off device in step S102 is a manual physical cutting tool independent of the simulated load device. Specifically, it should be understood that the protective grounding conductor cut-off device is connected in series between the charging gun line of the charging pile and the simulated load device to realize the physical on / off control of the protective grounding circuit. Before the test begins, the cut-off device should be placed in the conducting state to ensure that the protective grounding circuit between the charging pile and the simulated load device is normally connected. When it is necessary to simulate a protective grounding conductor loss fault, the cut-off device is manually operated to switch it to the off state, thereby physically interrupting the protective grounding circuit.

[0038] It should be noted that the specific structure, components and connection relationships of the protective grounding conductor cut-off device will be described in detail in Embodiment 2 of this specification, and will not be repeated here.

[0039] In some embodiments, the steady-state charging condition in step S103 refers to a stable operating stage in which the initial communication and connection status between the charging pile and the simulated load device have been completed, the protective grounding circuit remains continuous, the control guidance signal presents a stable pulse width modulation output, and the AC contactor inside the charging pile is in a closed state, thereby possessing the conditions for power transmission.

[0040] In some embodiments, the control guidance signal in step S103 is used to characterize the charging state, transmit control commands, and confirm the connection. When the charging pile is in a steady-state charging condition, the control guidance signal appears as follows: Figure 4 The continuous pulse width modulation waveform shown is stored as the first signal waveform.

[0041] In a preferred embodiment, if a first signal waveform conforming to the pulse width modulation characteristics cannot be obtained within a preset time, it should be determined that the charging pile has not entered the steady-state charging condition normally, and the subsequent test process should be terminated. At the same time, a prompt message indicating abnormal connection or charging start failure should be output.

[0042] In another preferred embodiment, the preset time is defined according to the maximum allowable time for the charging pile and the simulated load device to complete the connection confirmation and charging start-up process as specified in GB / T 18487.1—2023 standard, and this application does not limit it here.

[0043] After obtaining the first signal waveform and confirming that the charging pile is in a steady-state charging condition in step S103, this application manually operates the protective grounding conductor cut-off device by executing step S104 to simulate a protective grounding conductor loss fault. Taking the moment when the protective grounding conductor cut-off device switches to the off state as the time starting point, the control guidance signal waveform output by the charging pile is continuously collected, and the response waveform of the charging pile to the protective grounding conductor loss fault is recorded as the second signal waveform.

[0044] For example, the operator manually actuates the protective grounding conductor cutoff device, switching it from the on state to the off state. Specifically, it should be understood that the on state refers to the state where the protective grounding circuit is normally connected, and the off state refers to the state where the protective grounding circuit is physically interrupted. During the acquisition process, the oscilloscope or other signal acquisition equipment should be kept in continuous acquisition mode to ensure that subsequent changes in the control guide signal are completely recorded from the moment of switching.

[0045] In a preferred embodiment, to ensure the synchronization between the switching time and the acquisition start point, the operator can trigger the oscilloscope's single acquisition mode while manually actuating the cut-off device, or automatically start acquisition through the oscilloscope's level trigger function.

[0046] In some embodiments, the fault state DC level indicating the loss of protective grounding in step S105 is a DC level characterizing that the charging pile has detected the loss of the protective grounding conductor and entered a fault state.

[0047] In a preferred embodiment, the fault state DC level is +12V DC level, and when the second signal waveform abruptly changes to the following within a preset time threshold: Figure 5 When a stable +12V DC level is displayed, it indicates that the charging pile has successfully identified the loss of protective grounding and stopped power output.

[0048] In some embodiments, after completing the judgment in step S105, the detection result of the electrical continuity loss protection response of the protective grounding conductor of the charging pile, as described in step S106, is output based on the judgment result. Figure 6 As shown, it includes the following steps: S1071a, If in step S105 it is determined that the second signal waveform jumps from the pulse width modulation waveform to the DC level indicating the fault state of the protective grounding loss within a preset time threshold, then the detection result indicating that the electrical continuity loss protection function of the protective grounding conductor of the charging pile is qualified is output. S1071b, if in step S105 it is determined that the second signal waveform does not undergo the jump within the preset time threshold, or always maintains the pulse width modulation waveform, then output a detection result indicating that the electrical continuity loss protection function of the protective grounding conductor of the charging pile is unqualified.

[0049] In a preferred embodiment, the test results can be output in various ways, including but not limited to: displaying “qualified” or “unqualified” text or icons on the test system interface, generating a test report containing the judgment conclusion, and issuing a prompt signal through an audible and visual alarm device.

[0050] This application eliminates false disconnection errors caused by ground loops by cutting off all protective grounding electrical paths in the test environment except for the protective grounding conductor connected to the charging pile input terminal. By acquiring the second signal waveform starting from the moment the protective grounding conductor cut-off device switches to the off state, it achieves precise synchronization between the physical interruption moment and the signal acquisition start point. Furthermore, by judging whether the second signal waveform jumps from the first signal waveform to the fault state DC level within a preset time threshold, it provides an objective basis for determining whether the charging pile protection function meets the requirements of GB / T 18487.1—2023 standard. At the same time, the grounding isolation effectiveness verification mechanism ensures the single-point grounding condition of the test environment, significantly improving the accuracy, consistency, and reproducibility of the test results, and is suitable for standardized test scenarios such as type testing and 3C certification.

[0051] Example 2 A device for detecting the continuity loss response of the protective grounding conductor of a charging pile, used to perform the method described in Example 1, such as... Figures 7-9 As shown, it includes: Insulating housing 100; The input interface, located on the insulating housing 100, includes a live wire input terminal 210, a neutral wire input terminal 220, a protective grounding input terminal 230, and a control guide input terminal 240, for connecting the charging gun wire of the charging pile; the input interface adopts an AC charging interface form that conforms to national standards to ensure reliable plugging with the charging pile gun wire; The output interface, located on the insulating housing 100, includes a live wire output terminal 310, a neutral wire output terminal 320, a protective grounding output terminal 330, and a control guide output terminal 340, for connecting the analog load device; the output interface adopts a standard plug form corresponding to the input interface to match the input socket of the analog load device. A signal pass-through line is provided inside the insulating housing 100, which is used to electrically connect the input interface and the corresponding terminals of the output interface, except for the protective grounding terminal; A protective grounding conductor cut-off device 500 is disposed inside the insulating housing 100 and connected in series between the protective grounding input terminal 230 and the protective grounding output terminal 330, for realizing the physical on / off control of the protective grounding conductor.

[0052] Specifically, it should be understood that the signal pass-through line directly electrically connects the live wire input terminal of the input interface to the live wire output terminal of the output interface, directly electrically connects the neutral wire input terminal to the neutral wire output terminal, and directly electrically connects the control guide input terminal to the control guide output terminal. None of these connections involve any switching elements, ensuring that the transmission of live wire, neutral wire, and control guide signals between the charging pile and the simulated load device is unaffected by the disconnector.

[0053] In some embodiments, the protective grounding conductor cut-off device 500 is an external, manually operated mechanical disconnect switch.

[0054] In a preferred embodiment, the mechanical disconnect switch has a visible mechanical status indication structure and is a passive device.

[0055] Specifically, it should be understood that the operator can manually switch the protective grounding conductor cut-off device 500 between the on and off states. When the protective grounding conductor cut-off device 500 is in the on state, the circuit between the protective grounding input terminal 230 and the protective grounding output terminal 330 is connected, and the protective grounding circuit of the charging pile is normal. When the protective grounding conductor cut-off device 500 is in the off state, the electrical connection between the protective grounding input terminal 230 and the protective grounding output terminal 330 is physically interrupted, thereby simulating a protective grounding conductor loss fault.

[0056] In a preferred embodiment, the insulating housing 100 is further provided with an on / off status indicator that is linked to the protective grounding conductor cut-off device 500, for displaying whether the protective grounding conductor cut-off device 500 is currently in the on or off state.

[0057] In some embodiments, the detection device further includes a charging connection confirmation port CC, which is disposed on the input interface and the output interface and is directly electrically connected through the signal pass-through line. In addition, the input interface and the output interface also include one or more reserved ports NC1 and NC2 for adapting to the supplementary interface of a three-phase output charging pile.

[0058] Specifically, it should be understood that NC1 and NC2 in the input interface are used to connect the output gun line of the charging pile; NC1 and NC2 in the output interface are used to connect the simulated load at the vehicle end.

[0059] In some embodiments, the detection device also integrates functional modules that are linked with the protective grounding conductor cut-off device 500, including: a PE physical cut-off and continuity acquisition module, a CP level detection module, and a logic judgment and alarm indication module.

[0060] In a preferred embodiment, the PE physical disconnection and on / off acquisition module is used to realize the mechanical disconnection and status isolation acquisition of the protective grounding circuit, and is composed of a miniature circuit breaker, an isolation optocoupler, a voltage comparator, a logic circuit chip, an isolation auxiliary power supply, a current limiting resistor, and a pull-up resistor.

[0061] Specifically, it should be understood that the miniature circuit breaker is connected in series in the PE main circuit as a preferred implementation of the protective grounding conductor cut-off device 500. The miniature circuit breaker is a manually operated mechanical disconnecting switch with a conduction resistance ≤1mΩ, which does not generate additional impedance to the PE circuit and does not introduce an additional grounding path.

[0062] The primary side of the isolation optocoupler is powered by an independent isolation power supply, used for isolated acquisition of the on / off state of the miniature circuit breaker. A current-limiting resistor is connected in series in the primary side circuit of the isolation optocoupler to limit the primary side forward current. For example, the isolation optocoupler is a PC817 type, the isolation power supply Vdet is a +5V isolation auxiliary power supply with a primary side forward voltage drop Vf = 1.2V, and the designed forward current If = 17.3mA. The resistance value of the current-limiting resistor is calculated according to the following formula: It should be noted that the value of the current-limiting resistor is such that the primary-side detection current is in the milliampere range, which is much smaller than the PE main circuit current and does not affect the safety impedance characteristics of the PE circuit.

[0063] The secondary side of the isolation optocoupler adopts an open collector output structure and is connected to the system power supply via a pull-up resistor, outputting the PE status signal Signal_A.

[0064] Specifically, it should be understood that the working logic of the PE physical disconnection and on / off acquisition module is as follows: when the miniature circuit breaker is closed, its primary circuit is connected, the isolation optocoupler is connected, the secondary transistor is saturated and connected, and Signal_A outputs a low level, indicating that the PE circuit is connected; when the miniature circuit breaker is open, its primary circuit is cut off, the isolation optocoupler is turned off, the secondary transistor is turned off, and Signal_A outputs a high level, indicating that the PE circuit is disconnected.

[0065] In a preferred embodiment, the CP level detection module is used to identify the level of the control guidance signal, and consists of an RC filter unit, a voltage divider reference unit, a voltage comparator, and an output pull-up resistor.

[0066] Specifically, it should be understood that the RC filter unit includes a current-limiting resistor R3 connected in series between the CP signal input terminal and the non-inverting input terminal of the voltage comparator, and a filter capacitor C1 connected in parallel between the non-inverting input terminal of the voltage comparator and ground, forming a first-order RC low-pass filter for suppressing high-frequency electromagnetic interference.

[0067] For example, R3 = 1kΩ, C1 = 100nF, and its cutoff frequency fc ≈ 1.59KHz, effectively suppressing high-frequency interference while ensuring attenuation-free transmission of the 1kHz CP signal. Furthermore, the module's input impedance is ≥100kΩ, and its voltage drop across the vehicle's equivalent resistance is less than 1%, without altering the original electrical characteristics of the CP circuit.

[0068] The voltage divider reference unit is used to generate the threshold voltage and is composed of an upper voltage divider resistor R4 and a lower voltage divider resistor R5 connected in series between the system power supply and ground. The common node of the upper voltage divider resistor R4 and the lower voltage divider resistor R5 is connected to the inverting input terminal of the voltage comparator.

[0069] For example, the system power supply is +12V, R4=9kΩ, R5=3kΩ, according to the voltage divider formula: It should be noted that the generated inverting input reference voltage is 3V, which is between the 0V and +6V levels of the CP signal, thus balancing anti-interference capability and positive pulse recognition sensitivity.

[0070] In a preferred embodiment, the voltage comparator is an LM393 open-collector output comparator, whose output terminal is connected to the +12V system power supply via a pull-up resistor R6, and outputs the CP status signal Signal_B.

[0071] The working logic of the CP level detection module is as follows: when the CP signal is a +6V pulse level, the voltage at the non-inverting input is higher than the reference voltage (3V) at the inverting input, the comparator outputs a high level, and Signal_B is high, indicating that there is a PWM pulse in the CP; when the CP signal is a -12V steady-state level or a +12V fault-state DC level, the voltage at the non-inverting input is lower than the reference voltage at the inverting input, the comparator outputs a low level, and Signal_B is low, indicating that the CP is in a DC steady state.

[0072] In some embodiments, the logic determination and alarm indication module is used to perform logical determination based on the PE status signal Signal_A and the CP status signal Signal_B, and output an alarm signal when it is determined that the false disconnection condition is caused by a ground loop.

[0073] In a preferred embodiment, the logic decision unit uses a 74LS08 quad 2-input AND gate chip to implement pure hardware logic decision.

[0074] Specifically, the first set of AND gate channels of the AND gate chip is used, with pin 1 connected to the PE status signal Signal_A, pin 2 connected to the CP status signal Signal_B, and pin 3 outputting the alarm signal Alarm. Pin 14 of the AND gate chip is connected to the +12V system power supply, and pin 7 is connected to system ground.

[0075] The truth table for logical decisions is shown in Table 1: The alarm indication unit includes an alarm signal output terminal and a light-emitting diode (LED) indicator circuit connected thereto. The alarm signal Alarm is connected to the anode of the red LED via a current-limiting resistor R7, and the cathode of the LED is connected to system ground. When Alarm is high, the LED lights up, visually indicating a false disconnection fault; when Alarm is low, the LED is off.

[0076] In a preferred embodiment, the operating current of the light-emitting diode is limited to approximately 15mA to 25mA by the current-limiting resistor R7 to ensure the indicator brightness and protect the light-emitting device.

[0077] Specifically, it should be understood that the PE status signal Signal_A output by the PE physical disconnection and continuity acquisition module, and the CP status signal Signal_B output by the CP level detection module, are respectively connected to the two input terminals of the logic determination and alarm indication module. The logic determination and alarm indication module performs an AND logic operation on Signal_A and Signal_B and outputs an alarm signal Alarm, which is then displayed visually through the alarm indication unit.

[0078] The charging pile protective grounding conductor continuity loss response detection device provided by this invention achieves independent physical on / off control of the protective grounding circuit by setting the protective grounding conductor cutter as an external, manually operated mechanical disconnecting switch. This avoids the unreliability problems caused by contact carbonization, oxidation, or electromagnetic interference of the electronically controlled relay integrated inside the simulated load device. The mechanical disconnecting switch has a visual mechanical status indication structure, allowing operators to directly observe the current on / off status without relying on external indicating circuits. The signal direct-through line directly electrically connects the live wire, neutral wire, and control guide signal, ensuring that other signal transmissions between the charging pile and the simulated load device are not affected during the protective grounding conductor cut-off process. The mechanical disconnecting switch is a passive device, containing no control coil or auxiliary power supply, and does not introduce additional electromagnetic interference or grounding paths. Combined with the grounding isolation operation in Embodiment 1, it eliminates the influence of ground loop interference on the test results from a hardware perspective. Furthermore, the on / off status indicator linked to the protective grounding conductor cutter on the insulating housing further enhances the visualization of the operation and the traceability of the test process. The device has a simple structure, is plug-and-play, and requires no external power supply, which significantly improves the convenience of testing operations and the reliability of test results.

[0079] Example 3 A system for detecting the continuity loss response of the protective grounding conductor in a charging pile, such as Figure 9 , Figure 10 As shown, it includes: The protective grounding conductor continuity loss response detection device for the charging pile as described in Example 2 is connected in series between the charging gun line of the charging pile and the simulated load device. A control unit, used to connect to the detection device and the charging pile; wherein the control unit includes: The test environment configuration module is used to disconnect all protective grounding electrical paths except for the protective grounding conductor connected to the input terminal of the charging pile, so as to perform grounding isolation operation on the auxiliary equipment in the test environment; The signal acquisition module is used to acquire the control guidance signal when the charging pile enters the steady-state charging condition, as the first signal waveform; and to switch the protective grounding conductor cut-off device from the on state to the off state, and acquire the control guidance signal waveform output by the charging pile at the switching moment as the second signal waveform. The detection module is used to determine whether the second signal waveform changes from the first signal waveform to a DC level indicating a fault state of grounding loss within a preset time threshold; and outputs the detection result of the electrical continuity loss protection response of the charging pile's protective grounding conductor based on the determination result.

[0080] This invention provides a detection system for the continuity loss response of the protective grounding conductor of a charging pile. By combining the hardware detection device described in Embodiment 2 with a control unit including a test environment configuration module, a signal acquisition module, and a detection module, a closed-loop detection system is constructed, encompassing environmental optimization, fault simulation, and response determination. The test environment configuration module performs grounding isolation operations independently of the detection device, achieving functional decoupling between hardware isolation and software determination, facilitating system debugging and fault diagnosis. The signal acquisition module synchronously triggers waveform acquisition based on the switching moment of the protective grounding conductor cut-off device in the detection device, eliminating measurement errors caused by manual operation delays or clock asynchrony between instruments. The detection module incorporates preset time threshold judgment logic directly corresponding to the GB / T 18487.1 standard, eliminating the need for manual calculation and judgment, reducing the risk of misjudgment, and is adaptable to different types of charging piles and simulated load devices. The control unit can flexibly adjust the grounding isolation strategy according to the type of auxiliary equipment without modifying the hardware, exhibiting good versatility and scalability, significantly improving the standardization and applicability of the detection.

[0081] Example 4 A computer-readable storage medium, such as Figure 11 As shown, it stores program instructions, which, when executed, implement a method for detecting the continuity loss response of the protective grounding conductor of a charging pile as described in Embodiment 1 above.

[0082] The program instructions are stored in a computer-readable storage medium (such as a CD-ROM, USB flash drive, or portable hard drive) or on a network, and include several computer program instructions to cause a computing device (such as a personal computer, server, or network device) to execute the above-described method according to the embodiments of this application.

[0083] Through the above description of the embodiments, those skilled in the art will readily understand that the exemplary embodiments described herein can be implemented by software or by combining software with necessary hardware. Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention, and other modifications can be easily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and examples shown and described herein.

[0084] The apparatus, electronic device, and non-volatile computer storage medium and method provided in the embodiments of this specification are corresponding. Therefore, the apparatus, electronic device, and non-volatile computer storage medium also have similar beneficial technical effects as the corresponding method. Since the beneficial technical effects of the method have been described in detail above, the beneficial technical effects of the corresponding apparatus, electronic device, and non-volatile computer storage medium will not be repeated here.

[0085] Those skilled in the art will also know that, besides implementing the controller in the form of purely computer-readable program code, the same functions can be achieved by logically programming the method steps, making the controller take the form of logic gates, switches, application-specific integrated circuits (ASICs), programmable logic controllers (PLCs), and embedded microcontrollers. Therefore, such a controller can be considered a hardware component, and the devices included within it for implementing various functions can also be considered structures within that hardware component. Alternatively, the devices for implementing various functions can be considered as both software modules implementing the method and structures within a hardware component.

[0086] The systems, devices, modules, or units described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer. Specifically, a computer can be, for example, a personal computer, laptop computer, cellular phone, camera phone, smartphone, personal digital assistant, media player, navigation device, email device, game console, tablet computer, wearable device, or any combination of these devices.

[0087] For ease of description, the above apparatus is described by dividing it into various functional units. Of course, when implementing one or more embodiments of this specification, the functions of each unit can be implemented in one or more software and / or hardware.

[0088] Those skilled in the art will understand that the embodiments of this specification can be provided as methods, systems, or computer program products. Therefore, the embodiments of this specification can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects.

[0089] This specification is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this specification. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, produce a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0090] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0091] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0092] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0093] Memory may include non-persistent storage 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 is an example of computer-readable media.

[0094] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0095] This specification can be described in the general context of computer-executable instructions that are executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform a specific task or implement a specific abstract data type. This specification can also be practiced in distributed computing environments, where tasks are performed by remote processing devices connected via a communication network. In distributed computing environments, program modules can reside on local and remote computer storage media, including storage devices.

[0096] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0097] The above description is merely an embodiment of this specification and is not intended to limit the scope of one or more embodiments of this specification. Various modifications and variations can be made to one or more embodiments of this specification by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of one or more embodiments of this specification should be included within the scope of the claims of one or more embodiments of this specification.

Claims

1. A method for detecting the continuity loss response of the protective grounding conductor of a charging pile, characterized in that, Specifically, the following steps are included: Disconnect all protective grounding electrical paths except for the protective grounding conductor connected to the input terminal of the charging pile in order to perform grounding isolation operation on auxiliary equipment in the test environment; An external protective grounding conductor cut-off device is connected in series between the charging gun line of the charging pile and the simulated load device. The control guidance signal when the charging pile enters the steady-state charging condition is obtained and used as the first signal waveform; Switch the protective grounding conductor cut-off device from the on state to the off state, and obtain the control guidance signal waveform output by the charging pile at the switching moment as the starting point, as the second signal waveform; Determine whether the second signal waveform changes from the first signal waveform to a DC level indicating a fault state of grounding loss within a preset time threshold. Based on the judgment result, the detection result of the electrical continuity loss protection response of the protective grounding conductor of the charging pile is output.

2. The method for detecting the continuity loss response of the protective grounding conductor of a charging pile according to claim 1, characterized in that, The auxiliary equipment includes: The power supply for the simulated load device, the oscilloscope for monitoring the control guidance signal, the simulated load device itself, and other electrical equipment with protective grounding conductors in the detection system.

3. The method for detecting the continuity loss response of the protective grounding conductor of a charging pile according to claim 2, characterized in that, The grounding isolation operation performed on auxiliary equipment in the test environment includes the following steps: Disconnect the protective grounding conductor of the power supply line that supplies power to the simulated load device; An isolation transformer is used to power the oscilloscope used for monitoring and controlling the guidance signals, so that the oscilloscope is in a floating measurement state; Disconnect the independent grounding wire of the housing of the simulated load device.

4. The method for detecting the continuity loss response of the protective grounding conductor of a charging pile according to claim 1, characterized in that, Before acquiring the control guidance signal when the charging pile enters steady-state charging condition, the following steps are also included: Measure the equivalent resistance between the internal grounding node of the simulated load device and the power distribution system ground; Determine whether the equivalent resistance is greater than a preset resistance threshold; If the equivalent resistance is greater than the preset resistance threshold, the grounding isolation operation is confirmed to be effective, and subsequent steps are allowed to proceed. If the equivalent resistance is less than or equal to the preset resistance threshold, the grounding isolation operation is confirmed to be invalid, and the investigation continues to cut off any undiscovered protective grounding electrical paths.

5. The method for detecting the continuity loss response of the protective grounding conductor of a charging pile according to claim 1, characterized in that, The preset resistance threshold is set to 100kΩ.

6. A device for detecting the continuity loss response of the protective grounding conductor of a charging pile, used to perform the method as described in any one of claims 1-5, characterized in that, include: The input interface includes a live wire input terminal, a neutral wire input terminal, a protective grounding input terminal, and a control guide input terminal, which are used to connect the charging gun wire of the charging pile; The output interface includes a live wire output terminal, a neutral wire output terminal, a protective grounding output terminal, and a control guide output terminal, which are used to connect the analog load device. A signal pass-through line is used to electrically connect the input interface to the corresponding terminals of the output interface, excluding the protective grounding terminal. A protective grounding conductor cut-off device is connected in series between the protective grounding input terminal and the protective grounding output terminal to realize the physical on / off control of the protective grounding conductor.

7. The charging pile protective grounding conductor continuity loss response detection device according to claim 6, characterized in that, The protective grounding conductor cut-off device is an external, manually operated mechanical disconnect switch.

8. The charging pile protective grounding conductor continuity loss response detection device according to claim 7, characterized in that, The mechanical disconnect switch has a visible mechanical status indication structure and is a passive device.

9. The charging pile protective grounding conductor continuity loss response detection device according to claim 7, characterized in that, The protective grounding conductor cut-off device is equipped with an on / off status indicator.

10. A system for detecting the continuity loss response of the protective grounding conductor of a charging pile, characterized in that, include: The protective grounding conductor continuity loss response detection device for the charging pile as described in any one of claims 6-9 is connected in series between the charging gun line of the charging pile and the simulated load device. A control unit, used to connect to the detection device and the charging pile; wherein the control unit includes: The test environment configuration module is used to disconnect all protective grounding electrical paths except for the protective grounding conductor connected to the input terminal of the charging pile, so as to perform grounding isolation operation on the auxiliary equipment in the test environment; The signal acquisition module is used to acquire the control guidance signal when the charging pile enters the steady-state charging condition, as the first signal waveform; and to switch the protective grounding conductor cut-off device from the on state to the off state, and acquire the control guidance signal waveform output by the charging pile at the switching moment as the second signal waveform. The detection module is used to determine whether the second signal waveform changes from the first signal waveform to a DC level indicating a fault state of grounding loss within a preset time threshold; and outputs the detection result of the electrical continuity loss protection response of the charging pile's protective grounding conductor based on the determination result.

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