An electric leakage protection circuit, a charging module and a method

Abstract

This application relates to the field of electric vehicle charging technology, and provides a leakage current protection circuit, a charging module, and a method. The leakage current protection circuit is applied to a charging device and includes a leakage current detection unit, a control unit, a first switching unit, and a second switching unit. The first switching unit is connected in series between the input terminal of the charging device and the power supply. The second switching unit is connected in series between the output terminal of the charging device and the device to be charged. The leakage current detection unit is installed on the power supply line between the input terminal of the charging device and the power supply, or installed between the output terminal of the charging device and the second switching unit. The control unit is electrically connected to the first switching unit, the second switching unit, and the leakage current detection unit. The leakage current protection circuit provided by this application can solve the problem of leakage current during the use of AC slow charging piles causing damage to AC slow charging piles and new energy vehicles.

Description

Technical Field

[0001] This application belongs to the field of electric vehicle charging technology, and in particular relates to a leakage protection circuit, a charging module and a method. Background Technology

[0002] With the increasing popularity of electric vehicles, sales of new energy vehicles have risen rapidly. AC slow charging stations have become the optimal choice for charging new energy vehicles due to their low cost, charging time meeting daily living and work needs, and minimal battery wear. However, AC slow charging stations sometimes experience leakage during use, which can damage both the charging station and the new energy vehicle. Summary of the Invention

[0003] This application provides a leakage protection circuit, a charging module, and a method that can solve the problem of leakage damage to AC slow charging piles and new energy vehicles during use.

[0004] In a first aspect, embodiments of this application provide a leakage current protection circuit applied to a charging device, including a leakage current detection unit, a control unit, a first switch unit, and a second switch unit; the first switch unit is connected in series between the input terminal of the charging device and the power supply, the second switch unit is connected in series between the output terminal of the charging device and the device to be charged, the leakage current detection unit is installed on the power supply line between the input terminal of the charging device and the power supply or between the output terminal of the charging device and the second switch unit, and the control unit is electrically connected to the first switch unit, the second switch unit, and the leakage current detection unit respectively; the leakage current detection unit is used to detect the leakage current signal of the charging device and transmit the leakage current signal to the control unit; the control unit is used to control the first switch unit or the second switch unit to disconnect according to the leakage current signal.

[0005] In one possible implementation of the first aspect, the leakage current detection unit is installed on the power supply line between the input terminal of the charging device and the power supply. When the charging device is in the working state, the control unit controls the second switching unit to open according to the leakage current signal, and the operating state of the charging device switches to the standby state. When the charging device is in the standby state, the control unit controls the first switching unit to open according to the leakage current signal.

[0006] In one possible implementation of the first aspect, the first switching unit includes a circuit breaker; the circuit breaker is connected in series between the input terminal of the charging device and the power supply.

[0007] The second switching unit includes a relay; the relay is connected in series between the output terminal of the charging device and the device to be charged;

[0008] Both the circuit breaker and the relay are electrically connected to the control unit.

[0009] In one possible implementation of the first aspect, the leakage current detection unit includes a zero-sequence current transformer and a signal processing circuit; the zero-sequence current transformer is installed on the power supply line between the input terminal of the charging device and the power supply, the output terminal of the zero-sequence current transformer is electrically connected to the input terminal of the signal processing circuit, and the output terminal of the signal processing circuit is electrically connected to the control unit.

[0010] The zero-sequence current transformer is used to detect the leakage current signal of the charging device and transmit the leakage current signal to the signal processing circuit; the signal processing circuit is used to process the leakage current signal and transmit the processed leakage current signal to the control unit.

[0011] In one possible implementation of the first aspect, the control unit includes a control circuit, a first drive circuit, and a second drive circuit; the control circuit is electrically connected to the first drive circuit, the second drive circuit, and the signal processing circuit, respectively; the first drive circuit is electrically connected to the circuit breaker, and the second drive circuit is electrically connected to the relay.

[0012] The control circuit is used to send a second drive signal to the second drive circuit according to the leakage current signal and the operating state of the charging device, and the second drive circuit is used to drive the relay to disconnect according to the second drive signal; the control circuit is also used to send a first drive signal to the first drive circuit according to the leakage current signal and the operating state of the charging device, and the first drive circuit is used to drive the circuit breaker to disconnect according to the first drive signal.

[0013] In one possible implementation of the first aspect, the leakage protection circuit further includes a first indicating unit and a second indicating unit; both the first indicating unit and the second indicating unit are electrically connected to the control circuit.

[0014] The control circuit is further configured to control the second indicator unit to turn on when the second switch unit is disconnected; the control circuit is further configured to control the first indicator unit to turn on when the first switch unit is disconnected.

[0015] In one possible implementation of the first aspect, the leakage current detection unit is further configured to detect the duration of the leakage current signal and transmit the duration to the control unit; the control unit is configured to control the first switching unit or the second switching unit to disconnect based on the leakage current signal and the duration.

[0016] Secondly, embodiments of this application provide a charging module, including an AC-CDC conversion circuit, a charging device, and a leakage protection circuit provided in the first aspect of this application; the leakage protection circuit is electrically connected to the charging device and the AC-CDC conversion circuit respectively, and the charging device is connected in series between the power supply and the device to be charged.

[0017] The leakage protection circuit is used to detect the leakage current signal of the charging module, and control the first switching unit or the second switching unit to open according to the leakage current signal, so that the charging device is disconnected from the power supply or the charging device is disconnected from the device to be charged.

[0018] The AC-DC conversion circuit is used to convert the AC power input to the charging module into DC power to supply power to the leakage protection circuit.

[0019] In one possible implementation of the second aspect, the charging module further includes a wireless communication circuit; the wireless communication circuit is electrically connected to the leakage protection circuit, and the wireless communication circuit is used to enable remote communication between the charging module and the mobile terminal.

[0020] In one possible implementation of the second aspect, the charging module further includes a display circuit and a metering circuit; both the display circuit and the metering circuit are electrically connected to the leakage protection circuit; the metering circuit is used to collect the power information of the charging module; and the display circuit is used to display the power information of the charging module.

[0021] In one possible implementation of the second aspect, the charging module is mounted on a guide rail.

[0022] Thirdly, embodiments of this application provide a leakage current detection method, applied to the leakage current protection circuit provided in the first aspect of embodiments of this application, including:

[0023] Acquire the leakage current signal of the charging device;

[0024] The first or second switching unit is controlled to disconnect based on the leakage current signal, so that the charging device is disconnected from the power supply or the charging device is disconnected from the device to be charged.

[0025] In one possible implementation of the third aspect, when the leakage current detection unit is installed on the power supply line between the input terminal of the charging device and the power supply, the step of controlling the first switching unit or the second switching unit to disconnect according to the leakage current signal, so as to disconnect the charging device from the power supply or the charging device from the device to be charged, includes:

[0026] Obtain the operating status of the charging device;

[0027] When the charging device is in the working state and the leakage current signal is detected, the second switching unit is controlled to open, so that the charging device is disconnected from the device to be charged; wherein, when the second switching unit is opened, the operating state of the charging device is switched to the standby state;

[0028] When the charging device is in standby mode and the leakage current signal is detected, the first switching unit is controlled to open, so that the charging device is disconnected from the power supply.

[0029] The beneficial effects of the embodiments in this application compared with the prior art are:

[0030] The leakage current protection circuit provided in this application embodiment protects both the device to be charged and the charging device when leakage occurs. Specifically, the leakage current detection unit detects the leakage current signal of the charging device and transmits it to the control unit. The control unit controls the second switch unit to open based on the leakage current signal, disconnecting the charging device from the device to be charged and de-energizing the device, thus preventing damage to the device from the leakage current. Alternatively, the control unit controls the first switch unit to open based on the leakage current signal, disconnecting the charging device from the power supply and de-energizing the device. This cuts off the power supply as soon as leakage occurs in the charging pile, protecting the user and preventing damage to the charging device. The leakage current protection circuit provided in this application embodiment solves the problem that leakage during the use of AC slow charging piles, if not promptly protected, can damage the AC slow charging pile and the new energy vehicle, thus protecting the user, the AC slow charging pile, and the new energy vehicle.

[0031] It is understood that the beneficial effects of the second and third aspects mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the leakage protection circuit provided in one embodiment of this application;

[0034] Figure 2 This is a schematic diagram of the leakage protection circuit provided in another embodiment of this application;

[0035] Figure 3 This is a schematic diagram of the leakage protection circuit provided in another embodiment of this application;

[0036] Figure 4 This is a schematic diagram of the leakage protection circuit provided in another embodiment of this application;

[0037] Figure 5 This is a schematic diagram of the leakage protection circuit provided in another embodiment of this application;

[0038] Figure 6 This is a schematic diagram of the leakage protection circuit provided in another embodiment of this application;

[0039] Figure 7 This is a schematic diagram of the leakage protection circuit provided in another embodiment of this application;

[0040] Figure 8 This is a schematic diagram of the leakage protection circuit provided in another embodiment of this application;

[0041] Figure 9 This is a schematic diagram of the structure of a charging module provided in one embodiment of this application;

[0042] Figure 10 This is a schematic diagram of the structure of a charging module provided in another embodiment of this application;

[0043] Figure 11 This is a schematic diagram of the structure of a charging module provided in another embodiment of this application;

[0044] Figure 12 This is a schematic diagram of a leakage current detection method provided in an embodiment of this application;

[0045] Figure 13 This is a schematic diagram of a leakage current detection method provided in another embodiment of this application;

[0046] Figure 14This is a schematic diagram of a leakage current detection method provided in another embodiment of this application.

[0047] In the diagram: 10. Charging module; 100. Leakage protection circuit; 101. First switching unit; 1011. Circuit breaker; 102. Second switching unit; 1021. Relay; 103. Leakage current detection unit; 1031. Zero-sequence current transformer; 1032. Signal processing circuit; 104. Control unit; 1041. Control circuit; 1042. First drive circuit; 1043. Second drive circuit; 105. First indicating unit; 106. Second indicating unit; 200. AC / DC conversion circuit; 300. Wireless communication circuit; 400. Display circuit; 500. Metering circuit; 600. Charging device; 700. Power supply; 800. Device to be charged. Detailed Implementation

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

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

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

[0051] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if [the described condition or event] is detected" may be interpreted, depending on the context, as "once determined," "in response to determination," "once [the described condition or event] is detected," or "in response to detection of [the described condition or event]."

[0052] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0053] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0054] Currently, AC slow charging stations sometimes experience leakage during use. If leakage protection is not implemented promptly, it can damage both the AC slow charging station and the new energy vehicle. To address the deficiencies in existing technology, this application provides a leakage protection circuit, such as... Figure 1 As shown, the leakage protection circuit is applied to the charging device 600 and includes a leakage current detection unit 103, a control unit 104, a first switching unit 101, and a second switching unit 102. The first switching unit 101 is connected in series between the input terminal of the charging device 600 and the power supply 700. The second switching unit 102 is connected in series between the output terminal of the charging device 600 and the device 800 to be charged. The control unit 104 is electrically connected to the first switching unit 101, the second switching unit 102, and the leakage current detection unit 103.

[0055] Specifically, when the charging device 600 does not leak current, both the first switch unit 101 and the second switch unit 102 are in the conducting state, and the power supply 700 charges the device 800 to be charged normally through the charging device 600.

[0056] The leakage current detection unit 103 is installed at the input terminal of the charging device 600 and on the power supply line of the power supply 700. For example... Figure 1 As shown, the leakage current detection unit 103 is installed between the input terminal of the charging device 600 and the first switching unit 101. Figure 3 As shown, the leakage current detection unit 103 is installed between the power supply 700 and the first switching unit 101. Or as... Figure 2 As shown, the leakage current detection unit 103 is installed between the output terminal of the charging device 600 and the second switching unit 102.

[0057] The leakage current detection unit 103 continuously monitors the leakage current signal. When leakage occurs in the charging device 600, the leakage current detection unit 103 transmits the leakage current signal to the control unit 104. The control unit 104 controls the first switch unit 101 or the second switch unit 102 to disconnect based on the leakage current signal, thereby protecting the charging device 600 and the device 800 to be charged. Specifically, the control unit 104 controls the second switch unit 102 to disconnect based on the leakage current signal, disconnecting the charging device 600 from the device 800 to be charged, thus de-energizing the device 800 and preventing damage from the leakage current, thus protecting the device 800. Alternatively, the control unit 104 controls the first switch unit 101 to disconnect based on the leakage current signal, disconnecting the charging device 600 from the power supply 700, thus de-energizing the charging device 600. This means that the power is cut off when the charging pile leaks current, protecting the user and preventing damage to the charging device 600 from the leakage current, thus protecting the charging device 600. It can also prevent the first switching unit 101 and the second switching unit 102 from disconnecting.

[0058] The leakage protection circuit provided in this application embodiment solves the problem that leakage occurs during the use of AC slow charging piles, and if leakage protection is not carried out in time, it will damage the AC slow charging piles and new energy vehicles, thus protecting users, AC slow charging piles and new energy vehicles.

[0059] For example, when the charging device 600 experiences leakage, the leakage current detection unit 103 outputs a leakage current signal; when the charging device 600 does not experience leakage, the leakage current detection unit 103 does not output a signal.

[0060] The leakage current detection unit 103 is installed at the input terminal of the charging device 600 and on the power supply line of the power supply 700. For example... Figure 1 As shown, the leakage current detection unit 103 is installed between the input terminal of the charging device 600 and the first switching unit 101. Figure 3 As shown, the leakage current detection unit 103 is installed between the power supply 700 and the first switching unit 101. When the charging device 600 is in the working state, the control unit 104 controls the second switching unit 102 to open based on the leakage current signal, and the charging device 600 switches to the standby state. When the charging device 600 is in the standby state, the control unit 104 controls the first switching unit 101 to open based on the leakage current signal.

[0061] Specifically, when the charging device 600 does not leak current, both the first switch unit 101 and the second switch unit 102 are in the on state, and the power supply 700 charges the device 800 to be charged normally through the charging device 600.

[0062] The leakage current detection unit 103 continuously monitors the leakage current signal. When leakage occurs in the charging device 600, the leakage current detection unit 103 transmits the leakage current signal to the control unit 104. The control unit 104 controls the first switch unit 101 to open or controls the second switch unit 102 to open based on the leakage current signal and the operating state of the charging device 600. For example, when the charging device 600 is in the working state, the control unit 104 controls the second switch unit 102 to open based on the leakage current signal, thereby disconnecting the charging device 600 from the device 800 to be charged, de-energizing the device 800, preventing leakage current from damaging the device 800, and protecting the device 800. After the second switch unit 102 is opened, the charging device 600 switches to the standby state, and the leakage current detection unit 103 performs leakage current detection periodically. When the charging device 600 is in standby mode, the control unit 104 controls the first switch unit 101 to disconnect according to the leakage current signal, so that the power supply 700 is disconnected from the charging device 600, and the charging device 600 is de-energized. That is, the power supply is cut off when the pile body leaks current, which protects the user and prevents the leakage current from damaging the charging device 600, thus protecting the charging device 600.

[0063] It should be noted that the operating status of the charging device 600 can be obtained through the detection unit inside the charging device 600. Since the detection of the operating status of the charging device 600 is existing technology, it will not be described in detail here.

[0064] like Figure 4 As shown, the first switching unit 101 includes a circuit breaker 1011. The circuit breaker 1011 is connected in series between the input terminal of the charging device 600 and the power supply 700. The second switching unit 102 includes a relay 1021. The relay 1021 is connected in series between the output terminal of the charging device 600 and the device 800 to be charged. Both the circuit breaker 1011 and the relay 1021 are electrically connected to the control unit 104.

[0065] Specifically, when the charging device 600 does not leak current, both the first switch unit 101 and the second switch unit 102 are in the on state, and the power supply 700 charges the device 800 to be charged normally through the charging device 600.

[0066] like Figure 4As shown, the leakage current detection unit 103 is installed between the circuit breaker 1011 and the input terminal of the charging device 600. The leakage current detection unit 103 continuously monitors the leakage current signal. When leakage occurs in the charging device 600, the leakage current detection unit 103 transmits the leakage current signal to the control unit 104. The control unit 104 controls the circuit breaker 1011 to open or controls the relay 1021 to open based on the leakage current signal and the operating state of the charging device 600. For example, when the charging device 600 is in the working state, the control unit 104 controls the relay 1021 to open based on the leakage current signal, disconnecting the charging device 600 from the device 800 to be charged, thus de-energizing the device 800 and preventing damage from the leakage current, thereby protecting the device 800. After the relay 1021 opens, the charging device 600 switches to the standby state, and the leakage current detection unit 103 periodically performs leakage current detection. When the charging device 600 is in standby mode, the control unit 104 controls the circuit breaker 1011 to open based on the leakage current signal, disconnecting the power supply 700 from the charging device 600 and de-energizing it. This cuts off the power supply when there is leakage in the charging pile, protecting the user and preventing damage to the charging device 600 from the leakage current. It also prevents the relay 1021 and circuit breaker 1011 from tripping.

[0067] This should be understood as follows: since leakage of the charging device 600 itself is relatively rare, and considering the improvement of user experience, when the charging device 600 is in operation and leakage occurs, the leakage current detection unit 103 detects the leakage current signal of the charging device 600 and transmits the leakage current signal to the control unit 104. The control unit 104, based on the leakage current signal, first controls the relay 1021 to open, disconnecting the charging device 600 from the device 800 to be charged, thus de-energizing the device 800 and protecting it. After the relay 1021 opens, it only disconnects the charging line between the charging device 600 and the device 800 currently being charged. In scenarios where the charging device 600 is configured with multiple charging guns, it will not affect the charging of other devices 800, improving the user experience. The circuit breaker 1011 will only be tripped when leakage occurs in the charging device 600 itself, i.e., when leakage occurs in the charging pile itself, to minimize the impact on other users. After relay 1021 is disconnected, charging device 600 enters standby mode, and leakage current detection unit 103 periodically performs leakage current detection. When charging device 600 is in standby mode and leakage occurs, control unit 104 controls circuit breaker 1011 to open based on the leakage current signal, disconnecting charging device 600 from power supply 700 and de-energizing charging device 600. This cuts off power to the charging device 600 when leakage occurs in the charging pile, protecting both the user and the charging device 600. The above operation also allows for the step-by-step elimination of leakage faults.

[0068] like Figure 5 As shown, the leakage current detection unit 103 includes a zero-sequence current transformer 1031 and a signal processing circuit 1032. The zero-sequence current transformer 1031 is installed on the power supply line between the input terminal of the charging device 600 and the power supply 700, specifically between the circuit breaker 1011 and the input terminal of the charging device 600. The output terminal of the zero-sequence current transformer 1031 is electrically connected to the input terminal of the signal processing circuit 1032, and the output terminal of the signal processing circuit 1032 is electrically connected to the control unit 104.

[0069] Specifically, when the charging device 600 does not leak current, both the first switch unit 101 and the second switch unit 102 are in the on state, and the power supply 700 charges the device 800 to be charged normally through the charging device 600.

[0070] The zero-sequence current transformer 1031 continuously monitors the leakage current signal. When leakage occurs in the charging device 600, the zero-sequence current transformer 1031 transmits the leakage current signal to the signal processing circuit 1032. The signal processing circuit 1032 processes the leakage current signal and transmits the processed leakage current signal to the control unit 104. The control unit 104 controls the circuit breaker 1011 to open or controls the relay 1021 to open based on the leakage current signal and the operating status of the charging device 600. For example, when the charging device 600 is in the working state, the control unit 104 controls the relay 1021 to open based on the leakage current signal, disconnecting the charging device 600 from the device 800 to be charged, thus de-energizing the device 800 and preventing damage from the leakage current, thereby protecting the device 800. After the relay 1021 opens, the charging device 600 switches to the standby state, and the zero-sequence current transformer 1031 periodically performs leakage current detection. When the charging device 600 is in standby mode, the control unit 104 controls the circuit breaker 1011 to disconnect according to the leakage current signal, thereby disconnecting the power supply 700 from the charging device 600 and cutting off the power to the charging device 600. This means that the power is cut off when there is leakage in the pile body, which protects the user and prevents the leakage current from damaging the charging device 600, thus protecting the charging device 600.

[0071] For example, the zero-sequence current transformer 1031 can be a current transformer of model TA1419L-F3M. The signal processing circuit 1032 is an integrated circuit, specifically a bipolar linear integrated circuit LW54123A.

[0072] like Figure 6As shown, the control unit 104 includes a control circuit 1041, a first drive circuit 1042, and a second drive circuit 1043. The control circuit 1041 is electrically connected to the first drive circuit 1042, the second drive circuit 1043, and the signal processing circuit 1032. The first drive circuit 1042 is electrically connected to the circuit breaker 1011. The second drive circuit 1043 is electrically connected to the relay 1021. A zero-sequence current transformer 1031 is installed between the circuit breaker 1011 and the input terminal of the charging device 600.

[0073] Specifically, control circuit 1041 is used to send a first drive signal to first drive circuit 1042 based on leakage current signal and operating status of charging device 600. First drive circuit 1042 is used to drive circuit breaker 1011 to open based on the first drive signal. Control circuit 1041 is also used to send a second drive signal to second drive circuit 1043 based on leakage current signal and operating status of charging device 600. Second drive circuit 1043 is used to drive relay 1021 to open based on the second drive signal.

[0074] For example, when the charging device 600 does not leak current, both the first switch unit 101 and the second switch unit 102 are in the on state, and the power supply 700 charges the device 800 to be charged normally through the charging device 600.

[0075] The zero-sequence current transformer 1031 continuously detects the leakage current signal. When leakage occurs in the charging device 600, the zero-sequence current transformer 1031 transmits the leakage current signal to the signal processing circuit 1032. The signal processing circuit 1032 processes the leakage current signal and transmits the processed leakage current signal to the control circuit 1041. When the charging device 600 is in the working state, the control circuit 1041 sends a second drive signal to the second drive circuit 1043 based on the leakage current signal. The second drive circuit 1043 drives the relay 1021 to disconnect based on the second drive signal, disconnecting the charging device 600 from the device 800 to be charged, thus de-energizing the device 800 and preventing damage from the leakage current, thereby protecting the device 800. After the relay 1021 disconnects, the charging device 600 switches to the standby state, and the zero-sequence current transformer 1031 periodically performs leakage current detection. When the charging device 600 is in standby mode, the control circuit 1041 sends a first drive signal to the first drive circuit 1042 based on the leakage current signal. The first drive circuit 1042 drives the circuit breaker 1011 to open based on the first drive signal, disconnecting the charging device 600 from the power supply 700 and de-energizing the charging device 600. This cuts off the power supply when the charging pile leaks current, protecting the user and preventing damage to the charging device 600 from the leakage current, thus protecting the charging device 600.

[0076] For example, the control circuit 1041 can be a microcontroller processor, and the microcontroller processor can be a GD32F303RET6 chip.

[0077] In the event of a leakage fault, to facilitate quick identification of the leakage location by the user, the leakage protection circuit of this application embodiment is equipped with an indicator unit. For example... Figure 7 As shown, the leakage protection circuit also includes a first indicator unit 105 and a second indicator unit 106. Both the first indicator unit 105 and the second indicator unit 106 are connected to the control circuit 1041.

[0078] Specifically, when leakage occurs in the charging device 600 during operation, the zero-sequence current transformer 1031 detects the leakage current signal and transmits it to the signal processing circuit 1032. The signal processing circuit 1032 processes the leakage current signal and transmits the processed signal to the control circuit 1041. The control circuit 1041 sends a second drive signal to the second drive circuit 1043 based on the leakage current signal. The second drive circuit 1043 drives the relay 1021 to disconnect based on the second drive signal. Simultaneously, the control circuit 1041 also controls the second indicating unit 106 to open, indicating that leakage has occurred between the charging device 600 and the device 800 to be charged. When leakage occurs in the charging device 600 during standby, the zero-sequence current transformer 1031 detects the leakage current signal and transmits it to the signal processing circuit 1032. The signal processing circuit 1032 processes the leakage current signal and transmits it to the control circuit 1041. The control circuit 1041 sends a first drive signal to the first drive circuit 1042 based on the leakage current signal. The first drive circuit 1042 drives the circuit breaker 1011 to open based on the first drive signal. At the same time, the control circuit 1041 also controls the first indicator unit 105 to open to indicate that the charging device 600 itself has a leakage current, that is, the charging pile body has a leakage current.

[0079] For example, the first indicating unit 105 includes a first light-emitting diode (LED), and the second indicating unit 106 includes a second LED. The first LED and the second LED emit different lights to enable the user to quickly identify the location of the leakage.

[0080] like Figure 8As shown, circuit breaker 1011 includes two linked circuit breaker contacts CB1 and CB2, which are connected in series between the input terminal of charging device 600 and power supply 700. First drive circuit 1042 is electrically connected to the two linked circuit breaker contacts CB1 and CB2. Relay 1021 includes two linked relay contacts S1 and S2, which are connected in series between the output terminal of charging device 600 and device 800 to be charged. Second drive circuit 1043 is electrically connected to the two linked relay contacts S1 and S2.

[0081] Specifically, when the charging device 600 does not leak current, both the first switch unit 101 and the second switch unit 102 are in the conducting state, and the power supply 700 charges the device 800 to be charged normally through the charging device 600.

[0082] The zero-sequence current transformer 1031 continuously detects the leakage current signal. When leakage occurs in the charging device 600, the zero-sequence current transformer 1031 transmits the leakage current signal to the signal processing circuit 1032. The signal processing circuit 1032 processes the leakage current signal and transmits the processed leakage current signal to the control circuit 1041. When the charging device 600 is in the working state, the control circuit 1041 sends a second drive signal to the second drive circuit 1043 according to the leakage current signal. The second drive circuit 1043 drives two linked relay contacts S1 and S2 to open according to the second drive signal, disconnecting the charging device 600 from the device to be charged 800, de-energizing the device to be charged 800, preventing leakage current from damaging the device to be charged 800, and protecting the device to be charged 800. After the two linked relay contacts S1 and S2 open, the charging device 600 switches to the standby state, and the zero-sequence current transformer 1031 periodically performs leakage current detection. When the charging device 600 is in standby mode, the control circuit 1041 sends a first drive signal to the first drive circuit 1042 based on the leakage current signal. The first drive circuit 1042 drives the two linked circuit breaker contacts CB1 and CB2 to open according to the first drive signal, thereby disconnecting the charging device 600 from the power supply 700 and de-energizing the charging device 600. This cuts off the power supply when the charging pile leaks current, protecting the user and preventing damage to the charging device 600 from the leakage current, thus protecting the charging device 600.

[0083] For example, the power supply 700 is an AC power source, and the device to be charged 800 is an onboard charger (OBC).

[0084] Specifically, when the charging device 600 does not leak current, the two linked circuit breaker contacts CB1 and CB2 and the two linked relay contacts S1 and S2 are all in the conducting state, and the AC power supply charges the vehicle OBC normally through the charging device 600.

[0085] The zero-sequence current transformer 1031 continuously detects the leakage current signal. When leakage occurs in the charging device 600, the zero-sequence current transformer 1031 transmits the leakage current signal to the signal processing circuit 1032. The signal processing circuit 1032 processes the leakage current signal and transmits the processed leakage current signal to the control circuit 1041. When the charging device 600 is in the working state, the control circuit 1041 sends a second drive signal to the second drive circuit 1043 according to the leakage current signal. The second drive circuit 1043 drives two linked relay contacts S1 and S2 to open according to the second drive signal, disconnecting the charging device 600 from the vehicle OBC, de-energizing the vehicle OBC, preventing leakage current from damaging the vehicle OBC, and protecting the vehicle OBC. After the two linked relay contacts S1 and S2 open, the charging device 600 switches to the standby state, and the zero-sequence current transformer 1031 periodically performs leakage detection. When the charging device 600 is in standby mode, the control circuit 1041 sends a first drive signal to the first drive circuit 1042 based on the leakage current signal. The first drive circuit 1042 drives the two linked circuit breaker contacts CB1 and CB2 to open according to the first drive signal, disconnecting the charging device 600 from the AC power supply and de-energizing the charging device 600. This cuts off the power supply when the charging pile leaks current, protecting the user and preventing damage to the charging device 600 from the leakage current, thus protecting the charging device 600.

[0086] In real-world scenarios, interference signals such as leakage current signals may be generated. That is, if the charging device 600 does not leak current, the first switch unit 101 or the second switch unit 102 may be disconnected, causing the first switch unit 101 or the second switch unit 102 to malfunction, which reduces the user's experience during use.

[0087] To improve the detection accuracy of the leakage current signal, the leakage current detection unit 103 is also used to detect the duration of the leakage current signal and transmit the duration to the control unit 104. The control unit 104 controls the first switching unit 101 or the second switching unit 102 to open based on the leakage current signal and the duration.

[0088] Specifically, when the charging device 600 does not leak current, both the first switch unit 101 and the second switch unit 102 are in the conducting state, and the power supply 700 charges the device 800 to be charged normally through the charging device 600.

[0089] The leakage current detection unit 103 continuously monitors the leakage current signal. When leakage occurs in the charging device 600, the leakage current detection unit 103 transmits the leakage current signal to the control unit 104. Simultaneously, the leakage current detection unit 103 also detects the duration of the leakage current signal and transmits the duration to the control unit 104. When the duration exceeds a preset time, the control unit 104 controls either the first switching unit 101 or the second switching unit 102 to disconnect, thereby protecting the charging device 600 and the device 800 to be charged. By detecting the duration of the leakage current signal, the leakage current detection unit 103 determines whether it is an interference signal, thus improving the accuracy of leakage current protection.

[0090] like Figure 9 As shown, this application also provides a charging module 10, including an AC-DC conversion circuit 200, a charging device 600, and the aforementioned leakage protection circuit 100. The leakage protection circuit 100 is electrically connected to both the charging device 600 and the AC-DC conversion circuit 200. The charging device 600 is connected in series between the power supply 700 and the device 800 to be charged.

[0091] Specifically, when there is no leakage in the charging module 10, the power supply 700 charges the device 800 to be charged normally through the charging module 10.

[0092] The leakage current protection circuit 100 continuously monitors the leakage current signal. When leakage occurs in the charging module 10, the leakage current protection circuit 100 controls the second switching unit to open based on the leakage current signal, thereby disconnecting the charging device 600 from the device 800 to be charged, de-energizing the device 800, and preventing damage to the device 800 from the leakage current, thus protecting the device 800. Alternatively, the leakage current protection circuit 100 controls the first switching unit to open based on the leakage current signal, thereby disconnecting the charging device 600 from the power supply 700, and de-energizing the charging module 10. In other words, the power supply is cut off when there is leakage in the charging pile, protecting the user and preventing damage to the charging module 10 from the leakage current, thus protecting the charging module 10.

[0093] The AC-DC conversion circuit 200 is used to convert the AC power input to the charging module 10 into DC power to power the control unit in the leakage protection circuit 100.

[0094] It should be noted that the charging device 600 can be a traditional charging pile without leakage protection, while the charging module 10 is a charging pile with integrated leakage protection. In practical applications, the charging module 10 integrates an electricity meter, leakage protection circuit, and charging circuit, with the charging circuit being equivalent to the charging device 600.

[0095] like Figure 10As shown, the charging module 10 also includes a wireless communication circuit 300. The wireless communication circuit 300 is electrically connected to the leakage protection circuit 100.

[0096] Specifically, the charging module 10 can communicate wirelessly with the mobile terminal via the wireless communication circuit 300. Specifically, the charging module 10 can send its own status information to the mobile terminal for the user to view via the wireless communication circuit 300. The charging module 10 can also receive information sent by the user via the wireless communication circuit 300, enabling the user to wirelessly control the charging module 10.

[0097] like Figure 11 As shown, the charging module 10 also includes a display circuit 400 and a metering circuit 500. Both the display circuit 400 and the metering circuit 500 are electrically connected to the leakage protection circuit 100.

[0098] Specifically, the metering circuit 500 can collect the power information of the charging module 10 and send the collected power information to the leakage protection circuit 100. The leakage protection circuit 100 can display the collected power information through the display circuit 400 for user convenience.

[0099] For example, the charging module 10 is mounted on a guide rail. This mounting method makes the mounting position of the charging module 10 flexible and easier to install, which helps to promote the use of the charging module 10.

[0100] like Figure 12 As shown, this application also provides a leakage current detection method applied to the above-mentioned leakage current protection circuit, including:

[0101] S121. Obtain the leakage current signal of the charging device.

[0102] Specifically, the leakage current signal is obtained through the leakage protection circuit.

[0103] S122. Control the first switching unit or the second switching unit to disconnect according to the leakage current signal, so that the charging device is disconnected from the power supply or the charging device is disconnected from the device to be charged.

[0104] Specifically, the leakage current protection circuit controls the second switching unit to open based on the leakage current signal, thereby disconnecting the charging device from the device to be charged, de-energizing the device, and preventing damage from the leakage current, thus protecting the device. Alternatively, the leakage current protection circuit controls the first switching unit to open based on the leakage current signal, thereby disconnecting the charging device from the power supply, de-energizing the charging device. In other words, the power is cut off when there is leakage in the charging pile, protecting the user and preventing damage to the charging device from the leakage current.

[0105] like Figure 13 As shown, when the leakage current detection unit is installed on the power supply line between the input terminal of the charging device and the power supply, step S122 further includes:

[0106] S1221. Obtain the operating status of the charging device.

[0107] Specifically, the operating status of the charging device can be obtained through the detection unit inside the charging device.

[0108] S1222. When the charging device is in the working state and a leakage current signal is detected, the second switch unit is controlled to open, so that the charging device is disconnected from the device to be charged; wherein, when the second switch unit is opened, the operating state of the charging device is switched to the standby state.

[0109] Specifically, when the charging device is in operating mode and a leakage current signal is detected, the leakage protection circuit controls the second switching unit to open, thereby disconnecting the charging device from the device to be charged, de-energizing the device, preventing leakage current from damaging it, and protecting the device. When the second switching unit is open, the charging device switches to standby mode, and the leakage protection circuit periodically performs leakage current detection.

[0110] S1223. When the charging device is in standby mode and a leakage current signal is detected, the first switching unit is controlled to open so that the charging device is disconnected from the power supply.

[0111] Specifically, when the charging device is in standby mode and a leakage current signal is detected, the leakage protection circuit controls the first switch to open, thereby disconnecting the charging device from the power supply and cutting off the power to the charging device. In other words, the power is cut off when the charging pile leaks current, protecting the user and preventing the leakage current from damaging the charging device, thus protecting the charging device.

[0112] The following is combined Figure 14 The working process of step S122 is described in detail.

[0113] When the charging device is in standby mode and a leakage current signal is detected, the circuit breaker will trip if a leakage current signal is detected, disconnecting the charging device from the power supply and de-energizing it. After power loss, manual intervention is required to troubleshoot the fault before the charging device can be restored.

[0114] When the charging device is in working mode and a leakage current signal is detected, if a leakage current signal is detected, the control relay will open, disconnecting the charging device from the device being charged and de-energizing the device, putting the charging device into standby mode. The leakage current signal detection continues; if no leakage current signal is detected, the charging device remains in standby mode. If a leakage current signal is detected, the control circuit breaker will open, disconnecting the charging device from the power supply and de-energizing the device. After the charging device is powered off, manual intervention is required to troubleshoot the fault before it can be restored.

[0115] When the charging device is in working state and a leakage current signal is detected, if no leakage current signal is detected, the charging device is in charging until the charging is completed. After the charging is completed, the charging device is in standby state.

[0116] The leakage detection method provided in this application embodiment makes the leakage detection method of the circuit breaker in the leakage protection circuit consistent with the leakage detection method of the charging device, so that the two will not affect each other and can act in time when leakage occurs, thereby eliminating safety hazards.

[0117] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0118] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A leakage current protection circuit, applied to a charging device, characterized in that, The device includes a leakage current detection unit, a control unit, a first switch unit, and a second switch unit. The first switch unit is connected in series between the input terminal of the charging device and the power supply. The second switch unit is connected in series between the output terminal of the charging device and the device to be charged. The leakage current detection unit is installed on the power supply line between the input terminal of the charging device and the power supply or between the output terminal of the charging device and the second switch unit. The control unit is electrically connected to the first switch unit, the second switch unit, and the leakage current detection unit. The leakage current detection unit is used to detect the leakage current signal of the charging device and transmit the leakage current signal to the control unit; the control unit is used to control the first switching unit or the second switching unit to disconnect according to the leakage current signal. The leakage current detection unit is installed on the power supply line between the input terminal of the charging device and the power supply. When the charging device is in the working state, the control unit controls the second switch unit to open according to the leakage current signal, and the charging device switches to the standby state. When the charging device is in the standby state, the control unit controls the first switch unit to open according to the leakage current signal.

2. The leakage current protection circuit according to claim 1, characterized in that, The first switching unit includes a circuit breaker; the circuit breaker is connected in series between the input terminal of the charging device and the power supply. The second switching unit includes a relay; the relay is connected in series between the output terminal of the charging device and the device to be charged; Both the circuit breaker and the relay are electrically connected to the control unit.

3. The leakage protection circuit according to claim 2, characterized in that, The leakage current detection unit includes a zero-sequence current transformer and a signal processing circuit; the zero-sequence current transformer is installed on the power supply line between the input terminal of the charging device and the power supply, the output terminal of the zero-sequence current transformer is electrically connected to the input terminal of the signal processing circuit, and the output terminal of the signal processing circuit is electrically connected to the control unit. The zero-sequence current transformer is used to detect the leakage current signal of the charging device and transmit the leakage current signal to the signal processing circuit; the signal processing circuit is used to process the leakage current signal and transmit the processed leakage current signal to the control unit.

4. The leakage protection circuit according to claim 3, characterized in that, The control unit includes a control circuit, a first drive circuit, and a second drive circuit; the control circuit is electrically connected to the first drive circuit, the second drive circuit, and the signal processing circuit, respectively; the first drive circuit is electrically connected to the circuit breaker, and the second drive circuit is electrically connected to the relay. The control circuit is used to send a second drive signal to the second drive circuit according to the leakage current signal and the operating state of the charging device, and the second drive circuit is used to drive the relay to disconnect according to the second drive signal; the control circuit is also used to send a first drive signal to the first drive circuit according to the leakage current signal and the operating state of the charging device, and the first drive circuit is used to drive the circuit breaker to disconnect according to the first drive signal.

5. The leakage protection circuit according to claim 4, characterized in that, The leakage protection circuit further includes a first indicator unit and a second indicator unit; both the first indicator unit and the second indicator unit are electrically connected to the control circuit. The control circuit is further configured to control the second indicator unit to turn on when the second switch unit is disconnected; the control circuit is further configured to control the first indicator unit to turn on when the first switch unit is disconnected.

6. The leakage current protection circuit according to any one of claims 1-5, characterized in that, The leakage current detection unit is also used to detect the duration of the leakage current signal and transmit the duration to the control unit; the control unit is used to control the first switching unit or the second switching unit to disconnect according to the leakage current signal and the duration.

7. A charging module, characterized in that, The device includes an AC / DC conversion circuit, a charging device, and a leakage protection circuit as described in any one of claims 1-6; the leakage protection circuit is electrically connected to the charging device and the AC / DC conversion circuit respectively, and the charging device is connected in series between the power supply and the device to be charged; The leakage protection circuit is used to detect the leakage current signal of the charging module, and control the first switching unit or the second switching unit to open according to the leakage current signal, so that the charging device is disconnected from the power supply or the charging device is disconnected from the device to be charged. The AC-DC conversion circuit is used to convert the AC power input to the charging module into DC power to supply power to the leakage protection circuit.

8. The charging module according to claim 7, characterized in that, The charging module also includes a wireless communication circuit; the wireless communication circuit is electrically connected to the leakage protection circuit, and the wireless communication circuit is used to realize remote communication between the charging module and the mobile terminal.

9. The charging module according to claim 7, characterized in that, The charging module further includes a display circuit and a metering circuit; both the display circuit and the metering circuit are electrically connected to the leakage protection circuit; the metering circuit is used to collect the power information of the charging module; the display circuit is used to display the power information of the charging module.

10. A leakage current detection method, applied to the leakage current protection circuit according to any one of claims 1-6, characterized in that, include: Acquire the leakage current signal of the charging device; The first or second switching unit is controlled to disconnect based on the leakage current signal, so that the charging device is disconnected from the power supply or the charging device is disconnected from the device to be charged.

11. The leakage current detection method according to claim 10, characterized in that, When the leakage current detection unit is installed on the power supply line between the input terminal of the charging device and the power supply, the step of controlling the first switching unit or the second switching unit to disconnect according to the leakage current signal, so as to disconnect the charging device from the power supply or the charging device from the device to be charged, includes: Obtain the operating status of the charging device; When the charging device is in the working state and the leakage current signal is detected, the second switching unit is controlled to open, so that the charging device is disconnected from the device to be charged; wherein, when the second switching unit is opened, the operating state of the charging device is switched to the standby state; When the charging device is in standby mode and the leakage current signal is detected, the first switching unit is controlled to open, so that the charging device is disconnected from the power supply.

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