High-precision current detection device

Abstract

The utility model relates to the technical field of current testing, particularly provides a high-precision current detection device, and aims to solve the problem of how to accurately test micro current on the premise of not influencing an original circuit. In order to achieve the purpose, the high-precision current detection device comprises a fluxgate current sensor, a voltage measurement assembly, a wire and a power supply assembly. The wire passes through the fluxgate current sensor and is wound for a preset number of turns, and two ends of the wire are connected with a to-be-tested circuit; the input end of the voltage measuring assembly is connected with the voltage output port of the current sensor; the output end of the power supply assembly is connected with a power interface of the fluxgate current sensor. The current is measured through the fluxgate current sensor, and the measurement precision is higher. A sampling resistor does not need to be connected, the connected resistor is smaller, and on the premise that an original circuit is not affected, the tiny current can be tested more accurately.

Description

Technical Field

[0001] The utility model relates to the technical field of current testing, and specifically provides a high-precision current detection device. Background Art

[0002] In circuits, it is often necessary to detect tiny currents without connecting to the circuit. Tiny currents generally refer to currents in units of uA.

[0003] In existing technology, testing is often performed by connecting a sampling resistor. Specifically, the voltage across the sampling resistor is measured, and the current flowing through the resistor is calculated. However, this method requires the insertion of a high-resistance sampling resistor into the original circuit, significantly impacting the original circuit.

[0004] Therefore, the art needs a new high-precision current detection device to solve the above problems. Utility Model Content

[0005] In order to overcome the above-mentioned defects, the present invention is proposed to provide a solution or at least partially solve the problem of how to accurately test tiny currents without affecting the original circuit.

[0006] In a first aspect, the utility model provides a high-precision current detection device, the device comprising a fluxgate current sensor, a voltage measurement component, a wire, and a power supply component;

[0007] The wire passes through the fluxgate current sensor and is wound a preset number of times; both ends of the wire are used to connect to the circuit to be tested;

[0008] The input end of the voltage measurement component is connected to the voltage output port of the current sensor;

[0009] The output end of the power supply component is connected to the power interface of the fluxgate current sensor.

[0010] In one technical solution of the above-mentioned high-precision current detection device, the high-precision current detection device further includes a calibration resistor;

[0011] One end of the calibration resistor is connected to one end of the power supply component, and the other end of the calibration resistor is connected to the other end of the wire passing through the fluxgate current sensor.

[0012] In one technical solution of the above-mentioned high-precision current detection device, the high-precision current detection device further includes a calibration resistance switch;

[0013] One end of the calibration resistor switch is connected to one end of the calibration resistor, and the other end of the calibration resistor switch is connected to one end of the power supply component.

[0014] In a technical solution of the above-mentioned high-precision current detection device, there are multiple calibration resistors and calibration resistor switches, and the resistance values of each calibration resistor are different. One calibration resistor and one calibration resistor switch are connected in series to form a calibration series branch; multiple calibration series branches are connected in parallel.

[0015] In one technical solution of the above-mentioned high-precision current detection device, the preset number of turns is 10 turns or 5 turns.

[0016] In one technical solution of the above-mentioned high-precision current detection device, the device further includes a device output interface;

[0017] The device output interface is connected to the output end of the voltage measurement component.

[0018] In one technical solution of the above-mentioned high-precision current detection device, the wire passing through the fluxgate current sensor and wound around a preset number of turns is fixed to the fluxgate current sensor by glue.

[0019] In one technical solution of the above-mentioned high-precision current detection device, the device further includes a device power supply interface;

[0020] The device power interface is connected to the input end of the power supply component.

[0021] In one technical solution of the above-mentioned high-precision current detection device, the high-precision current detection device further includes a temperature sensor.

[0022] In a technical solution of the above-mentioned high-precision current detection device, there are multiple fluxgate current sensors and wires, one wire passes through one fluxgate current sensor and is wound a preset number of times to form a sensor branch, and both ends of the wire of each sensor branch are used to connect to the circuit to be tested.

[0023] The above one or more technical solutions of the present invention have at least one or more of the following beneficial effects:

[0024] In the technical solution for implementing the present invention, the high-precision current detection device of the present invention includes a fluxgate current sensor, a voltage measurement component, a wire, a power supply component, and a power supply interface of the device. The wire passes through the fluxgate current sensor and is wound a preset number of times; the two ends of the wire are used to connect to the circuit to be measured; the input end of the voltage measurement component is connected to the voltage output end of the fluxgate current sensor; and the output end of the power supply component is connected to the power supply interface of the fluxgate current sensor. Through the above-mentioned setting method, since the present invention measures the current through the fluxgate current sensor, it has higher measurement accuracy. At the same time, when measuring the current, it is an indirect measurement, and there is no need to connect a sampling resistor. The measurement can be achieved by only connecting the wire to the circuit to be measured, and it has a smaller access resistance. Therefore, the present application can achieve more accurate testing of small currents without affecting the original circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The disclosure of the present invention will become more easily understood with reference to the accompanying drawings. Those skilled in the art will readily appreciate that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. Furthermore, similar numbers in the figures represent similar components, where:

[0026] Figure 1 1 is a schematic diagram of the main components of a high-precision current detection device according to an embodiment of the present utility model;

[0027] Figure 2 1 is a schematic diagram of the main components of a high-precision current detection device according to an embodiment of the present utility model.

[0028] Reference Signs List :

[0029] 1: Fluxgate current sensor; 2: Voltage measurement component; 3: Wire; 4: Power supply component; 5: Calibration resistor; 6: Calibration resistor switch; 7: Device power interface; 8: Device output interface. DETAILED DESCRIPTION

[0030] Some embodiments of the present invention are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0031] It should be noted that, in the description of the present utility model, the terms "first", "second" and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0032] Furthermore, it should be noted that, in the description of this utility model, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0033] See attached Figure 1 , Figure 1 FIG. 1 is a schematic diagram of the main components of a high-precision current detection device according to an embodiment of the present invention. Figure 1 As shown, in an embodiment of the present invention, the high-precision current detection device mainly includes a fluxgate current sensor 1, a voltage measurement component 2, a wire 3, and a power supply component 4; the wire 3 passes through the fluxgate current sensor 1 and is wound a preset number of times; the two ends of the wire 3 are used to connect to the circuit to be measured; the input end of the voltage measurement component 2 is connected to the voltage output end of the fluxgate current sensor 1; the output end of the power supply component 4 is connected to one end of the wire 3 passing through the fluxgate current sensor 1, and the other end of the power supply component 4 is connected to the power interface of the wire 3 of the fluxgate current sensor 1. The power supply component 4 supplies power to the fluxgate current sensor 1. The voltage measurement component 2 can be used to measure voltage and convert the measurement result into current, thereby obtaining a high-precision current detection result. The fluxgate current sensor is a sensor that uses the magnetic effect of a high-permeability magnetic core to measure the weak magnetic field of a tiny current, and has inherent stability and higher accuracy.

[0034] In this embodiment, since current is measured using fluxgate current sensor 1, higher measurement accuracy is achieved. Furthermore, both ends of wire 3 can be directly connected to the circuit under test, making current measurement indirect. No sampling resistor is required; measurement is achieved simply by connecting wire 3 to the circuit under test, resulting in a smaller access resistance. Consequently, more accurate testing of minute currents is possible without affecting the original circuit.

[0035] In one embodiment, the voltage measuring component 2 can be a voltmeter. When connected to the circuit to be measured, the measured voltage is U 测 , data processing can be performed based on the following formula (1) to obtain the current test results.

[0036] I 测 = (U 测 -b) / k (1)

[0037] Among them, I 测 is the current test result, b is the zero point parameter, and k is the slope parameter.

[0038] In one embodiment, Figure 1 As shown, the preset number of turns can be 10 turns. Passing the wire 3 through the fluxgate current sensor 1 and winding it 10 turns can improve the measurement accuracy.

[0039] In another embodiment, the preset number of laps may be 5 laps.

[0040] In one embodiment, the wire 3, which passes through the fluxgate current sensor 1 and is wound a predetermined number of times, is secured to the fluxgate current sensor 1 with glue. This ensures that the position of the wire 3 relative to the fluxgate current sensor 1 is fixed, improving measurement consistency and avoiding the need to pass the measured circuit through the fluxgate current sensor 1 without being fixed for each measurement.

[0041] In one embodiment, the cross-sectional area of the wire 3 may be greater than or equal to 1 square millimeter. Selecting a thicker wire 3 can reduce the access resistance, for example, the access resistance may be less than 10 mΩ.

[0042] In one embodiment, see the attached Figure 2 , Figure 2 FIG. 1 is a schematic diagram of the main components of a high-precision current detection device according to an embodiment of the present utility model. Figure 2 As shown, the high-precision current detection device may further include a calibration resistor 5; one end of the calibration resistor 5 is connected to one end of the power supply component 4, and the other end of the calibration resistor 5 is connected to the other end of the wire 3 passing through the fluxgate current sensor 1.

[0043] In this embodiment, if Figure 2 As shown, the high-precision current detection device may further include a calibration resistor switch 6; one end of the calibration resistor switch 6 is connected to one end of the calibration resistor 5, and the other end of the calibration resistor switch 6 is connected to one end of the power supply component 4. The calibration resistor switch 6 can be used to connect and disconnect the calibration resistor 5.

[0044] In one embodiment, there may be multiple calibration resistors 5 and calibration resistor switches 6, each of which has a different resistance value. One calibration resistor 5 is connected in series with one calibration resistor switch 6 to form a calibration series branch; and multiple calibration series branches are connected in parallel.

[0045] In this embodiment, since the zero point parameters and slope parameters of the fluxgate current sensor 1 may change after a period of time, the calibration of the fluxgate current sensor 1, such as zero point calibration and slope calibration, can be achieved by connecting calibration series branches in parallel. In an example, Figure 1As shown, there are two calibration series branches. Zero-point calibration involves setting the output voltage of the fluxgate current sensor 1 to zero when no current flows. Slope calibration involves switching calibration resistors 5 of different standard resistance values to generate corresponding calibration currents in conductor 3. The slope is then obtained by performing a linear fit based on the measured multiple calibration currents. Power supply assembly 4 can power the calibration series branches.

[0046] In an example, the output voltage of the power supply component 4 is 12V, the test range of the high-precision current detection device is 0.12mA to 0.24mA, and the two calibration resistors 5 can be 100kΩ and 50kΩ respectively.

[0047] In one embodiment, the number of calibration resistors 5 can be varied, for example, five.

[0048] In one embodiment, the high-precision current detection device may further include a temperature sensor, which obtains the temperature of the fluxgate current sensor 1 through the temperature sensor, thereby performing temperature compensation on the test result of the fluxgate current sensor 1 according to the temperature to further improve the current detection accuracy.

[0049] In one embodiment, multiple fluxgate current sensors 1 and multiple conductors 3 can be provided. Each conductor 3 passes through a fluxgate current sensor 1 and is wound a predetermined number of times to form a sensor branch. Each sensor branch has two ends connected to a circuit under test. Specifically, a high-precision current detection device can include multiple fluxgate current sensors 1 and multiple conductors 3. Each fluxgate current sensor 1 and each conductor 3 form a sensor branch. Multiple sensor branches can share a common power supply assembly 4, voltage measurement assembly 2, and calibration resistor 5, enabling simultaneous testing of multiple circuits under test.

[0050] In one embodiment, Figure 1 and Figure 2 As shown, the high-precision current detection device may further include a device output interface 8, which may be connected to the output end of the voltage measurement component 2. The device output interface 8 may be used to output the test results of the voltage measurement component, such as connecting to a PC to display the test results on the PC.

[0051] In one embodiment, Figure 1 and Figure 2 As shown, the high-precision current detection device may further include a device power interface 7, which may be connected to the input end of the power supply component. The device power interface is used to connect to an external power supply, such as 220V AC power.

[0052] Furthermore, it should be understood that since the configuration of each module is merely for the purpose of illustrating the functional units of the apparatus of the present invention, the physical devices corresponding to these modules may be the processor itself, or a portion of the software in the processor, a portion of the hardware, or a combination of software and hardware. Therefore, the number of modules in the figure is merely illustrative.

[0053] Those skilled in the art will appreciate that the modules in the device can be adaptively split or combined. Such splitting or combining of specific modules will not cause the technical solution to deviate from the principles of the present invention. Therefore, the technical solutions after splitting or combining will fall within the scope of protection of the present invention.

[0054] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

Claims

1. A high-precision current detection device, characterized in that: The device includes a fluxgate current sensor, a voltage measurement component, a conductor and a power supply component; The wire passes through the fluxgate current sensor and is wound a preset number of times; both ends of the wire are used to connect to the circuit to be tested; The input end of the voltage measurement component is connected to the voltage output port of the fluxgate current sensor; The output end of the power supply component is connected to the power interface of the fluxgate current sensor.

2. The high-precision current detection device according to claim 1, characterized in that: The high-precision current detection device also includes a calibration resistor; One end of the calibration resistor is connected to one end of the power supply component, and the other end of the calibration resistor is connected to the other end of the wire passing through the fluxgate current sensor.

3. The high-precision current detection device according to claim 2, characterized in that: The high-precision current detection device also includes a calibration resistance switch; One end of the calibration resistor switch is connected to one end of the calibration resistor, and the other end of the calibration resistor switch is connected to one end of the power supply component.

4. The high-precision current detection device according to claim 3, characterized in that: There are multiple calibration resistors and calibration resistor switches, each of which has a different resistance value. One calibration resistor is connected in series with one calibration resistor switch to form a calibration series branch; multiple calibration series branches are connected in parallel.

5. The high-precision current detection device according to claim 1, characterized in that: The preset number of laps is 10 laps or 5 laps.

6. The high-precision current detection device according to any one of claims 1 to 5, characterized in that: The device also includes a device output interface; The device output interface is connected to the output end of the voltage measurement component.

7. The high-precision current detection device according to claim 1, characterized in that: The wire passing through the fluxgate current sensor and wound with a preset number of turns is fixed to the fluxgate current sensor by glue.

8. The high-precision current detection device according to any one of claims 1 to 5, characterized in that: The device also includes a device power interface; The device power interface is connected to the input end of the power supply component.

9. The high-precision current detection device according to claim 1, characterized in that: The high-precision current detection device further includes a temperature sensor.

10. The high-precision current detection device according to any one of claims 1 to 5 or 7 or 9, characterized in that: There are multiple fluxgate current sensors and wires. One wire passes through one fluxgate current sensor and is wound a preset number of times to form a sensor branch. Both ends of the wire of each sensor branch are used to connect to the circuit to be tested.

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