A circuit breaker, an electric meter and a current sensor thereof

Abstract

A circuit breaker, an electric meter and a current sensor thereof. The circuit breaker and the electric meter include the current sensor of the present invention. The current sensor includes a conductor component and a first PCB board provided with a TMR sensor component. The first PCB board is embedded in the middle of the conductor component, and the TMR sensor component is embedded in the middle of the conductor component. The magnetic field induction intensity in the middle of the conductor component is relatively large, so that the interference to the TMR sensor component is relatively small. In addition, this embedded structure makes the TMR sensor component closer to the inner center of the conductor component, so that the magnetic field induction intensity is maximized, and the problem of phase interference of the sensor can be effectively solved.

Description

Technical Field

[0001] The invention relates to a low-voltage electrical control element, in particular to a circuit breaker, an electric meter and a current sensor thereof. Background Art

[0002] The current sensor is an important component of the electronic low-voltage circuit breaker. It can detect the relevant information of the main circuit current signal and transmit this information to the controller to determine the main circuit current fault. Most traditional current sensors use a combination of magnetic core and coil to detect current information by sensing the changes in the main circuit magnetic field. Affected by the performance of the magnetic core and the processing technology of the coil, the current current sensor has the disadvantages of large size and high cost, and some important parameters of the current sensor, such as frequency response, response time, linearity, accuracy, etc., cannot be directly measured.

[0003] Based on the above reasons, the new coreless current sensor based on tunnel magnetoresistance technology has begun to attract everyone's attention. This sensor has the characteristics of high precision, wide linear range and wide application range, but is limited by the shielding magnetic field device and is still easily affected by phase interference during use. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide a circuit breaker, an electric meter and a current sensor thereof with simple structure and strong anti-interference.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A current sensor comprises a conductor component and a first PCB board provided with a TMR sensor component, wherein the first PCB board is embedded in the middle of the conductor component, and the TMR sensor component is embedded in the middle of the conductor component.

[0007] Preferably, it also includes a second PCB board, which is arranged on the surface of the conductor component, and the first PCB board is connected to the second PCB board, and a power supply unit and a signal processing module are arranged on the second PCB board, the power supply unit is used to supply power to the TMR sensor component and the signal processing module, and the signal processing module is used to collect the voltage signal of the TMR sensor component and the temperature signal around the TMR sensor component.

[0008] Furthermore, the TMR sensing component includes two TMR tunnel magnetoresistive chips, which are respectively arranged on two opposite sides of the first PCB board, and the distances between the two TMR tunnel magnetoresistive chips and the center of the conductor component are equal.

[0009] Furthermore, the first PCB board vertically protrudes from one side surface of the conductor component, the second PCB board is arranged parallel to one side surface of the conductor component, and the first PCB board and the second PCB board are located on the same side of the conductor component.

[0010] Furthermore, a mounting groove is provided in the middle of the conductor component, the first PCB board is vertically assembled in the mounting groove, and the first PCB board is connected to the second PCB board through respective pads.

[0011] Furthermore, the second PCB is arranged close to one side surface of the conductor component, a pad of the second PCB corresponds to the mounting groove, and the first PCB is assembled in the mounting groove and passes through the pad of the second PCB.

[0012] Furthermore, the conductor component is a copper busbar, and the TMR sensor assembly includes two TMR tunnel magnetoresistive chips, which are distributed on a cross-section of the copper busbar in a back-to-back manner, and the distances between the two TMR tunnel magnetoresistive chips and the center of the copper busbar are equal.

[0013] Furthermore, the signal processing module includes a signal conditioning unit and a temperature acquisition unit. The signal conditioning unit is used to receive the voltage signal transmitted by the TMR sensor component and transmit it to the outside after processing the voltage signal. The temperature acquisition unit is used to collect the temperature signal around the TMR sensor component and transmit the collected temperature signal to the outside.

[0014] Furthermore, the signal processing module also includes an interface unit for external connection, the interface unit is respectively connected to an external power supply and a user end, the interface unit is connected to a power supply unit so that the external power supply provides voltage to the power supply unit through the interface unit, and the interface unit is respectively connected to a signal conditioning unit and a temperature acquisition unit, and is used to transmit the electrical signal received by the signal conditioning unit and the temperature signal collected by the temperature acquisition unit to the user end.

[0015] A circuit breaker comprises a housing, wherein the above-mentioned current sensor is arranged in the housing.

[0016] An electric meter comprises a shell, in which the above-mentioned current sensor is arranged.

[0017] The present invention provides a current sensor, wherein a first PCB board provided with a TMR sensor component is embedded in the middle of a conductor component. The magnetic field induction intensity in the middle of the conductor component is relatively large, so that the interference to the TMR sensor component is relatively small. In addition, the embedded structure makes the TMR sensor component closer to the inner center of the conductor component, so that the magnetic field intensity sensed by the TMR sensor component is maximized, and the problem of phase interference between sensors can be effectively solved.

[0018] In addition, the two TMR tunnel magnetoresistance chips of the TMR sensor assembly are arranged on both sides of the first PCB board in a back-to-back manner, and the two TMR tunnel magnetoresistance chips are at an equal distance from the center of the conductor component, further reducing the degree of interference of the TMR tunnel magnetoresistance chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1-2 It is a structural schematic diagram of a current sensor of the present invention;

[0020] Figure 3 It is a schematic diagram of the principle of a current sensor of the present invention. DETAILED DESCRIPTION

[0021] The following is combined with Figures 1 to 3 The given embodiments further illustrate the specific implementation of a circuit breaker, an electric meter and a current sensor thereof of the present invention. A circuit breaker, an electric meter and a current sensor thereof of the present invention are not limited to the description of the following embodiments.

[0022] A current sensor comprises a conductor component 3 and a first PCB board 1 provided with a TMR sensor component, wherein the first PCB board 1 is embedded in the middle of the conductor component 3, and the TMR sensor component is embedded in the middle of the conductor component 3.

[0023] The present invention provides a current sensor, wherein a first PCB board 1 provided with a TMR sensor component is embedded in the middle of a conductor component 3. The magnetic field induction intensity in the middle of the conductor component 3 is relatively large, so that the interference to the TMR sensor component is relatively small. In addition, this embedded structure makes the TMR sensor component closer to the inner center of the conductor component 3, so that the magnetic field intensity sensed by the TMR sensor component is maximized, and the problem of phase interference between sensors can be effectively solved.

[0024] Preferably, Figure 1-2 The current sensor embodiment includes a conductor component 3, a first PCB board 1 and a second PCB board 2, wherein the first PCB board 1 is embedded in the middle of the conductor component 3, the second PCB board 2 is arranged on the surface of the conductor component 3, and the first PCB board 1 is connected to the second PCB board 2, a TMR sensor component is arranged on the first PCB board 1, the TMR sensor component is embedded in the middle of the conductor component 3, the TMR sensor component is used to sense the magnetic field around the conductor component 3 after power is turned on to generate a voltage signal, and a power supply unit and a signal processing module are arranged on the second PCB board 2, the power supply unit is used to supply power to the TMR sensor component and the signal processing module, and the signal processing module is used to collect the voltage signal of the TMR sensor component and the temperature signal around the TMR sensor component.

[0025] In the current sensor of this embodiment, the TMR sensor component, the power supply unit, and the signal processing module are respectively arranged on two PCB boards, and the first PCB board 1 provided with the TMR sensor component is embedded in the middle of the conductor component 3. The magnetic field induction intensity in the middle of the conductor component 3 is relatively large, so that the interference to the TMR sensor component is relatively small, and this embedded structure makes the TMR sensor component closer to the inner center of the conductor component 3, so that the magnetic field intensity sensed by the TMR sensor component is maximized, which can effectively solve the problem of phase interference of the sensor. It should be noted that in the present application, the power supply unit and the signal processing module arranged on the second PCB board 2 can be arranged on the first PCB board 1, but at this time the area of ​​the first PCB board 1 needs to be large enough, which will cause the height of the current sensor to be raised and the overall volume to be relatively large.

[0026] Specific, combined Figure 1-2 An embodiment of a current sensor is provided, a current sensor includes a conductor component 3, a first PCB board 1 and a second PCB board 2, preferably the conductor component 3 is a copper bar, a mounting groove 31 is opened near the middle of the copper bar, the first PCB board 1 is assembled in the mounting groove 31 to be embedded in the middle of the copper bar, the second PCB board 2 is arranged on the surface of the copper bar and is located on the same side of the copper bar as the first PCB board 1, preferably as Figure 1-2As shown, the second PCB board 2 is arranged parallel to and close to the surface of the copper bar, a pad on the second PCB board 2 corresponds to the mounting groove 31, the first PCB board 1 vertically passes through the pad of the second PCB board 2, and the first PCB board 1 and the second PCB board 2 are connected through their respective pads. Of course, the second PCB board 2 can also be arranged on one side of the first PCB board 1. In this case, the second PCB board 2 may not be provided with a pad corresponding to the mounting groove 31, and it is only necessary to ensure that it can be connected to the first PCB board 1. A TMR sensor component is arranged on the first PCB board 1, and the TMR sensor component is used to sense the magnetic field around the conductor component 3 after power is applied to generate a voltage signal. Since the first PCB board 1 is embedded in the middle of the copper bar, the TMR sensor component is located in the mounting groove 31 closer to the inner center of the copper bar, and the magnetic field around the copper bar after power is applied is sensed by the TMR sensor component to generate a voltage signal, and the magnetic induction intensity near the middle of the copper bar is relatively large, so that the TMR sensor component is less disturbed. Specifically, the TMR sensor assembly includes two TMR tunnel magnetoresistive chips, which are respectively arranged on opposite sides of the first PCB board 1, and the two TMR tunnel magnetoresistive chips are distributed on the cross-section of the copper bar in a back-to-back manner, and the distances between the two TMR tunnel magnetoresistive chips and the inner center of the copper bar are equal, which is conducive to solving the phase interference. A power supply unit and a signal processing module are arranged on the second PCB board 2, and the power supply unit is used to supply power to the TMR sensor assembly and the signal processing module, and the signal processing module is used to collect the voltage signal of the TMR sensor assembly and the temperature signal around the TMR sensor assembly.

[0027] The signal processing module includes a signal conditioning unit and a temperature acquisition unit. The TMR sensor component is used to sense the surrounding magnetic field when the conductor component 3 is energized to generate a voltage signal. The signal conditioning unit is used to receive the voltage signal transmitted by the TMR sensor component and transmit it to the outside after processing the voltage signal. The temperature acquisition unit is used to collect the temperature signal around the TMR sensor component and transmit the collected temperature signal to the outside.

[0028] Preferably, the signal processing module also includes an interface unit for external connection, the interface unit is respectively connected to an external power supply and a user end, the external power supply is connected to the V+ input terminal and the V- input terminal of the interface unit, and the V+ output terminal and the V- output terminal of the interface unit are connected to the power supply unit, so that the external power supply provides voltage to the power supply unit through the interface unit; the signal output terminal of the interface unit is connected to the user end, and the signal input terminal of the interface unit is respectively connected to the signal output terminals of the signal conditioning unit and the temperature acquisition unit, and is used to transmit the electrical signal received by the signal conditioning unit and the temperature signal collected by the temperature acquisition unit to the user end, and the user end performs data processing after reading the corresponding electrical signal and temperature signal, calculates the measurement error caused by the temperature, and calculates the size of the tested circuit after compensation for use.

[0029] When the current sensor is in use, the current flowing through the conductor component 3 is generally within 1000A, and the first PCB board 1 and the second PCB board 2 will not be damaged due to high temperature. Of course, in order to avoid a short circuit, an insulating material needs to be added between the second PCB board 2 and the conductor component 3; if necessary, a heat insulating material can also be added between the second PCB board 2 and the conductor component 3.

[0030] A circuit breaker includes a housing, in which a current sensor as described above is arranged, and the current sensor is connected between the connection terminals of the static contact of the circuit breaker through a conductor component 3. Of course, the current sensor of the present application can also be used in relays and electric meters. As a part of the current sensor, the conductor component 3 is not only used to assemble a first PCB board provided with a TMR sensor component, but also can be used as a wiring device, which is easy to assemble.

[0031] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A current sensor, characterized in that: It comprises a conductor component (3) and a first PCB board (1) provided with a TMR sensor component, wherein the first PCB board (1) is embedded in the middle of the conductor component (3), and the TMR sensor component is embedded in the middle of the conductor component (3); the TMR sensor component comprises two TMR tunnel magnetoresistive chips, the two TMR tunnel magnetoresistive chips are respectively arranged on two opposite sides of the first PCB board (1), and the distances between the two TMR tunnel magnetoresistive chips and the center of the conductor component (3) are equal; and the conductor component (3) is a copper busbar.

2. A current sensor according to claim 1, characterized in that: The invention also comprises a second PCB board (2), wherein the second PCB board (2) is arranged on the surface of the conductor component (3), and the first PCB board (1) is connected to the second PCB board (2). A power supply unit and a signal processing module are arranged on the second PCB board (2), wherein the power supply unit is used to supply power to the TMR sensor component and the signal processing module, and the signal processing module is used to collect a voltage signal of the TMR sensor component and a temperature signal around the TMR sensor component.

3. A current sensor according to claim 2, characterized in that: The first PCB board (1) protrudes vertically from a side surface of the conductor component (3), the second PCB board (2) is arranged parallel to a side surface of the conductor component (3), and the first PCB board (1) and the second PCB board (2) are located on the same side of the conductor component (3).

4. A current sensor according to claim 2, characterized in that: A mounting groove (31) is provided in the middle of the conductor component (3), the first PCB board (1) is vertically mounted in the mounting groove (31), and the first PCB board (1) and the second PCB board (2) are connected via respective solder pads.

5. A current sensor according to claim 4, characterized in that: The second PCB board (2) is arranged in close contact with a side surface of the conductor component (3); a soldering pad of the second PCB board (2) corresponds to the mounting groove (31); and the first PCB board (1) is assembled in the mounting groove (31) and passes through the soldering pad of the second PCB.

6. A current sensor according to claim 2, characterized in that: The signal processing module includes a signal conditioning unit and a temperature acquisition unit. The signal conditioning unit is used to receive the voltage signal transmitted by the TMR sensor component and transmit it outward after processing the voltage signal. The temperature acquisition unit is used to collect the temperature signal around the TMR sensor component and transmit the collected temperature signal outward.

7. A current sensor according to claim 6, characterized in that: The signal processing module also includes an interface unit for external connection, the interface unit is respectively connected to an external power supply and a user end, the interface unit is connected to a power supply unit so that the external power supply provides voltage to the power supply unit through the interface unit, and the interface unit is respectively connected to a signal conditioning unit and a temperature acquisition unit, and is used to transmit the electrical signal received by the signal conditioning unit and the temperature signal collected by the temperature acquisition unit to the user end.

8. A circuit breaker, characterized in that: A current sensor as claimed in any one of claims 1 to 7 is provided.

9. An electric meter, characterized in that: A current sensor as claimed in any one of claims 1 to 7 is provided.

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