Electric leakage sensor of charging equipment and charging equipment

Abstract

The electric leakage sensor comprises a magnetic induction module and a signal processing module which are separately arranged, and a connector is detachably arranged on the magnetic induction module; when the connector and the magnetic induction module are detached, the magnetic induction module adopts wave soldering to realize PCB installation, and the signal processing module adopts an SMT patch mode to realize PCB installation; when the connector is installed on the magnetic induction module, the magnetic induction module is communicated with external equipment through the connector. According to the invention, the board distribution difficulty of a user can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of leakage sensors, in particular to a leakage sensor for a charging device and the charging device. Background Art

[0002] A leakage sensor is a current detection device based on the fluxgate principle, applying mutual inductor and magnetic modulation technologies, which isolates and converts a small current signal within a certain bandwidth into a standard analog signal such as a linear proportional DC current or voltage, or into a digital signal that is processed by digital signal processing and transmitted in a certain protocol manner.

[0003] Leakage sensors are widely used in fields such as power systems, industrial control systems, and household appliances to monitor and protect circuits from damage caused by leakage. Especially in the new energy field, it plays a crucial role in the safety of the high-voltage system of electric vehicles and is currently mainly applied to electric vehicle charging protection and insulation impedance monitoring.

[0004] Currently, the magnetic induction module and the signal processing module of most leakage sensors are integrated on one structure, with a relatively large volume, and the installation and maintenance of the product are relatively complicated. Summary of the Utility Model

[0005] Based on the above description, the utility model provides a leakage sensor for a charging device and the charging device to solve the problems of the relatively large volume of the leakage sensor and the complicated installation and maintenance.

[0006] On the one hand, the utility model of the present application provides a leakage sensor for a charging device, including a separately arranged magnetic induction module and a signal processing module, and a connector is detachably arranged on the magnetic induction module;

[0007] When the connector is detached from the magnetic induction module, the magnetic induction module realizes PCB installation by wave soldering, and the signal processing module realizes PCB installation by SMT patching;

[0008] When the connector is installed on the magnetic induction module, the magnetic induction module realizes connection with external devices through the connector.

[0009] Based on the above technical solution, the utility model can be further improved as follows.

[0010] Further, the magnetic induction module includes a housing and a magnetic core coil arranged inside a magnetic core housing, the housing includes a connecting portion, and installation blocks are arranged on both sides of the connecting portion;

[0011] The connector is provided with a clamping hole, and when the connector is connected to the magnetic induction module, the installation blocks are inserted into the clamping hole.

[0012] Furthermore, the installation clamping block includes a first side wall and a second side wall which are oppositely arranged. The first side wall is an inclined surface, and the second side wall includes a vertical surface and an inclined surface;

[0013] A buckle is also fixed on the side wall of the connector around the clamping hole.

[0014] Furthermore, a positioning piece also protrudes from the end face of the connecting portion. A positioning through hole is provided on the connector. When the connector is connected to the magnetic induction module, the positioning piece is correspondingly inserted into the positioning through hole, and the side wall of the positioning piece is in contact with the side wall of the positioning through hole.

[0015] Furthermore, the signal processing module includes a PCBA and a shielding cover arranged outside the PCBA. The circuit architecture of the PCBA includes:

[0016] A magnetic induction module driving circuit, which is used to drive the magnetic induction module to generate an oscillation signal with a fixed frequency;

[0017] A signal sampling circuit, which is used to collect the current signal transmitted by the magnetic induction module and convert it into a voltage signal;

[0018] A signal processing circuit, which is used to amplify and filter the voltage signal;

[0019] An MCU signal analysis circuit, which is correspondingly connected to the signal processing circuit one by one, is used to convert and calculate the magnitude of the leakage current, and at the same time, according to the leakage standard threshold of the charging pile, output a leakage level;

[0020] Leakage output, which is used to transmit a leakage alarm signal to the charging pile.

[0021] Furthermore, the magnetic core coil includes a magnetic core, a secondary side primary winding wound around the magnetic core, and a secondary side secondary winding communicated with the secondary side primary winding;

[0022] The circuit architecture of the PCBA further includes:

[0023] A zero point calibration circuit, which is correspondingly connected to the secondary side secondary winding one by one, and is used to calibrate the zero point parameters during the curve fitting of the product end;

[0024] A gain calibration circuit, which is used to calibrate the gain parameters during the curve fitting of the product end.

[0025] Furthermore, the circuit architecture of the PCBA further includes:

[0026] An oscillation frequency acquisition circuit, which is correspondingly connected to the magnetic induction module driving circuit module one by one, and is used to collect the fixed oscillation frequency signal of the magnetic induction module;

[0027] The half-duplex serial port transceiver circuit is connected one-to-one with the MCU signal analysis circuit module, and is used to implement the internal serial port protocol of the MCU and the upgrade of the APP program.

[0028] On the other hand, the utility model of the present application provides a charging device, which includes the above-mentioned leakage sensor and a leakage action mechanism connected to the leakage sensor. The leakage action mechanism is used to disconnect the power supply line when the magnitude of the leakage current signal detected by the leakage sensor is greater than the threshold set by the standard.

[0029] Compared with the prior art, the technical solution of the present application has the following beneficial technical effects:

[0030] 1. The present utility model adopts a scheme in which the magnetic induction module and the signal processing module are separated. The magnetic induction module can be connected to the user control board by a connector or installed on the PCB by wave soldering. The signal processing module is installed on the PCB by SMT patching. This separated installation method not only reduces the difficulty of the user's circuit board layout, but also makes debugging and replacement more convenient.

[0031] 2. The design of the signal processing module of the present application can provide circuit drive for the magnetic induction module, collect the current signal transmitted by the magnetic induction module, and after processing and analysis, transmit a leakage alarm signal to the charging pile, thereby realizing the leakage protection of the charging pile during the charging process.

[0032] 3. The connector of the present application is detachably connected to the magnetic induction module, so that the connector is convenient for installation and disassembly, and thus it is possible to choose whether to install the connector according to different functional requirements, and the applicability is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is the effect diagram of the leakage sensor in the embodiment of the present application;

[0034] Figure 2 It is the overall structure diagram of the magnetic induction module in the embodiment of the present application;

[0035] Figure 3 It is the exploded structure diagram of the magnetic induction module in the embodiment of the present application;

[0036] Figure 4 is Figure 3 the enlarged schematic diagram at A in

[0037] Figure 5 It is the exploded structure diagram of the signal processing module in the embodiment of the present application.

[0038] In the drawings, the list of components represented by each reference numeral is as follows:

[0039] 1. Magnetic induction module; 11. Housing; 111. Upper housing; 112. Lower housing; 12. Installation clamping block; 121. First side wall; 122. Second side wall; 13. Positioning piece; 14. Core coil; 141. Core; 142. Secondary side primary winding; 143. Secondary side secondary winding; 15. Core protection box; 151. Upper cover; 152. Lower cover; 2. Connector; 21. Clamping hole; 22. Positioning through hole; 23. Conducting wire; 24. Plug-in part; 25. Buckle piece; 3. Signal processing module; 31. PCBA; 32. Shielding cover. Detailed implementation manner

[0040] To facilitate the understanding of this application, the following will describe this application more comprehensively with reference to the relevant drawings. Embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of this application more thorough and comprehensive.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the specification of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0042] This application provides a leakage sensor for a charging device. Referring to Figure 1 , it includes a separately arranged magnetic induction module 1 and a signal processing module 3. The leakage sensor of this application is used to detect various leakage currents of the charging device.

[0043] Referring to Figures 2-5 , the magnetic induction module 1 is used to detect the leakage current signal of the charging device, and includes an annular housing 11. The housing specifically includes an upper housing 111 and a lower housing 112 that are buckled up and down; a core protection box 15 is arranged inside the housing 11. The core protection box 15 specifically includes an upper cover 151 and a lower cover 152 that are buckled to each other. A core coil 14 is arranged inside the core protection box 15. The core coil 14 includes a core 141, a secondary side primary winding 142 wound around the core 141, and a secondary side secondary winding 143 communicated with the secondary side primary winding 142.

[0044] The current loop to be monitored passes through the through hole in the middle of the housing 11. When a leakage fault occurs in one or more phases of the load end of the charging device to the ground, it causes a current deviation in the original balanced loop, that is, a residual current is generated. The generated residual current can be collected in real time by the magnetic induction module 1 and transmitted to the signal processing module 3 to complete the analysis and determination of the current signal.

[0045] The output end of the magnetic induction module 1 is detachably provided with a connector 2, and the output end of the connector 2 is also connected with a wire 23 and a plug-in connector 24 in sequence, so that the magnetic induction module 1 can be connected to an external device through the connector 2. Specifically, the signal processing module 3 uses an SMT patch to achieve installation with a corresponding PCB; when the connector 2 and the magnetic induction module 1 are disassembled, the magnetic induction module 1 uses wave soldering to achieve installation with a corresponding PCB; when the connector 2 and the magnetic induction module 1 are installed, the magnetic induction module 1 is connected to an external device through the connector 2, thereby being able to meet different installation methods of the magnetic induction module 1 and having a wider applicability.

[0046] The shell 11 includes a connecting portion, and mounting blocks 12 are fixed on both side walls opposite to each other of the connecting portion. The mounting blocks 12 include a first side wall 121 and a second side wall 122 that are relatively arranged. The first side wall 121 is an inclined surface, and the second side wall 122 includes an inclined surface and a vertical surface. The connector 2 is provided with card holes 21 corresponding to the number of the mounting blocks 12. When the connector 2 and the shell 11 are connected, the mounting blocks 12 are inserted into the card holes 21 one by one. When the connector 2 and the shell 11 are connected, the connector 2 first contacts the first side wall 121. After the installation is completed, the side wall of the card hole 21 abuts against the vertical surface of the second side wall 122.

[0047] A buckle piece 25 is also fixed on the side wall of the connector 2 located around the snap-in hole 21; when the connector 2 needs to be separated from the magnetic induction module 1, the operator can move the buckle piece 25 to cause the area where the connector 2 contacts the connecting part to deform, thereby allowing the connector 2 to slide along the inclined surface of the second side wall 122 until the connector 2 and the connecting part are separated.

[0048] Furthermore, a positioning piece 13 extends from the end face of the connecting portion, and a positioning through hole 22 is opened on the connector 2. When the connector 2 is connected to the magnetic induction module 1, the positioning piece 13 is correspondingly inserted into the positioning through hole 22, and the side wall of the positioning piece 13 is in contact with the side wall of the positioning through hole 22. By providing the positioning piece 13, the convenience of installing the connector 2 can be improved and the alignment of the connector 2 and the magnetic induction module 1 can be facilitated.

[0049] The signal processing module 3 is used to provide circuit driving for the magnetic induction module 1, and collect, amplify, filter and analyze the current signal transmitted by the magnetic induction module 1. The signal processing module 3 includes a PBCA 31 and a shielding cover 32 arranged outside the PCBA 31.

[0050] The PCBA circuit architecture includes a magnetic induction module drive circuit, a signal sampling circuit, a signal processing circuit, an MCU signal analysis circuit, and a leakage current output circuit. The magnetic induction module drive circuit is connected to the secondary side primary winding 142 of the magnetic induction module 1 in a one-to-one correspondence. This module includes an H-bridge composed of four MOS transistors and a comparison circuit with analog signal comparison function. The middle of the H-bridge passes through the magnetic induction module 1 to drive the magnetic induction module 1 to generate an oscillation signal with a fixed frequency; the signal sampling circuit is connected to the magnetic induction module drive circuit module in a one-to-one correspondence, and is used to collect the current signal passing through the H-bridge to the ground. This signal is linearly related to the current input to the magnetic induction module 1 within a corresponding time range; the signal processing circuit is connected to the signal sampling circuit module in a one-to-one correspondence, and is used to filter the DC component of the current signal collected by the sampling circuit and amplify the signal at the same time; the MCU signal analysis circuit is connected to the signal processing circuit in a one-to-one correspondence, and is used to convert and calculate the magnitude of the leakage current, and output the leakage level according to the leakage standard threshold of the charging pile; the leakage current output circuit is connected to the MCU signal analysis circuit in a one-to-one correspondence, and is used to drive and output the leakage level.

[0051] In a preferred embodiment, the signal processing module 3 further includes a zero point calibration circuit, a gain calibration circuit, an oscillation frequency acquisition circuit, and a half-duplex serial port transceiver circuit. The zero point calibration circuit is connected to the secondary side secondary winding 143 in a one-to-one correspondence, and is used to calibrate the zero point parameter during the curve fitting at the product end; the gain calibration circuit is used with the magnetic induction module 1 to calibrate the gain parameter during the curve fitting at the product end; the oscillation frequency acquisition circuit is connected to the magnetic induction module 1 drive circuit in a one-to-one correspondence, and is used to collect the fixed oscillation frequency signal of the magnetic induction module 1; the half-duplex serial port transceiver circuit is connected to the MCU signal analysis circuit in a one-to-one correspondence, and is used to realize the upgrade of the internal serial port protocol of the MCU and the APP program.

[0052] In one embodiment, the zero point calibration circuit further includes an input pin for commands, which is used to receive the zero current calibration instruction to realize the zero point calibration function.

[0053] In one embodiment, the gain calibration circuit further includes an input pin for commands, which is used to receive the gain calibration instruction to realize the gain calibration function.

[0054] In one embodiment, the half-duplex serial port transceiver circuit further includes an input pin for serial port commands, which is used to multiplex the gain calibration function and the half-duplex serial port command transceiver function.

[0055] In this application, the signal processing module 3 drives the circuit comparison circuit and the H-bridge circuit through the magnetic induction module 1 to drive the magnetic induction module 1 to generate an oscillation signal with a fixed frequency; the signal sampling circuit collects the current signal transmitted by the magnetic induction module 1 through an internal sampling resistor and converts it into a voltage signal; the signal processing circuit amplifies and filters the voltage signal converted by the sampling circuit; and transmits it to the MCU for the operation and analysis of the leakage current magnitude. The MCU signal analysis circuit realizes the determination of different thresholds and different leakage waveforms according to different charging pile leakage standards; finally, through the leakage output circuit, a leakage alarm signal is transmitted to the charging pile.

[0056] This application also provides a charging device, including the above-mentioned leakage sensor and a leakage action mechanism connected to the leakage sensor. The action mechanism is used to disconnect the power supply line when the magnitude of the leakage current signal detected by the leakage detection device is greater than the threshold set by the standard.

[0057] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A leakage sensor for a charging device, characterized in that: It comprises a magnetic induction module (1) and a signal processing module (3) which are separately arranged, wherein the magnetic induction module (1) is detachably provided with a connector (2); When the connector (2) and the magnetic induction module (1) are disassembled, the magnetic induction module (1) is mounted on a PCB using wave soldering, and the signal processing module (3) is mounted on a PCB using an SMT patch; When the connector (2) is mounted on the magnetic induction module (1), the magnetic induction module (1) is connected to an external device via the connector (2).

2. A leakage sensor for a charging device according to claim 1, characterized in that: The magnetic induction module (1) comprises a housing (11) and a magnetic core coil (14) arranged in a protective shell of a magnetic core (141); the housing (11) comprises a connecting portion, and mounting blocks (12) are arranged on both sides of the connecting portion; The connector (2) is provided with a card connection hole (21); when the connector (2) is connected to the magnetic induction module (1), the installation card block (12) is inserted into the card connection hole (21).

3. The leakage sensor of a charging device according to claim 2, characterized in that: The mounting block (12) comprises a first side wall (121) and a second side wall (122) which are arranged opposite to each other, the first side wall (121) is an inclined surface, and the second side wall (122) comprises a vertical surface and an inclined surface; A buckle piece (25) is also fixed on the side wall of the connector (2) located around the clamping hole (21).

4. The leakage sensor of a charging device according to claim 2, characterized in that: A positioning piece (13) extends from the end surface of the connection portion, and a positioning through hole (22) is provided on the connector (2). When the connector (2) is connected to the magnetic induction module (1), the positioning piece (13) is correspondingly inserted into the positioning through hole (22), and the side wall of the positioning piece (13) is in contact with the side wall of the positioning through hole (22).

5. The leakage sensor of a charging device according to claim 2, characterized in that: The signal processing module (3) comprises a PCBA (31) and a shielding cover (32) arranged outside the PCBA (31), and the PCBA circuit architecture comprises: A magnetic induction module driving circuit, used to drive the magnetic induction module (1) to generate an oscillation signal of a fixed frequency; A signal sampling circuit, used for collecting the current signal transmitted by the magnetic induction module (1) and converting it into a voltage signal; A signal processing circuit, used for amplifying and filtering the voltage signal; The MCU signal analysis circuit is connected to the signal processing circuit in a one-to-one correspondence, and is used to convert and calculate the leakage current, and output the leakage level according to the standard threshold of the charging pile leakage; Leakage output is used to transmit leakage alarm signal to the charging pile.

6. A leakage sensor for charging equipment according to claim 5, characterized in that: The magnetic core coil (14) comprises a magnetic core (141), a secondary-side primary winding (142) wound outside the magnetic core (141), and a secondary-side secondary winding (143) connected to the secondary-side primary winding (142); The PCBA circuit architecture also includes: A zero point calibration circuit, connected in a one-to-one correspondence with the secondary winding (143) on the secondary side, and used to implement zero point parameter calibration during curve fitting at the product end; The gain calibration circuit is used to implement gain parameter calibration during curve fitting at the product end.

7. A leakage sensor for a charging device according to claim 6, characterized in that: The PCBA circuit architecture also includes: An oscillation frequency acquisition circuit, connected in a one-to-one correspondence with the magnetic induction module (1) drive circuit module, and used for acquiring a fixed oscillation frequency signal of the magnetic induction module (1); The half-duplex serial port transceiver circuit is connected one-to-one with the MCU signal analysis circuit module to implement the internal serial port protocol of the MCU and the upgrade of the APP program.

8. A charging device, comprising the leakage sensor according to any one of claims 1 to 7, characterized in that: It also includes a leakage action mechanism connected to the leakage sensor, and the leakage action mechanism is used to disconnect the power supply line when the leakage sensor detects that the magnitude of the leakage current signal is greater than the threshold set by the standard.

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