A low frequency current transformer circuit based on hardware processing module correction

Abstract

This invention addresses the problem in existing low-frequency current transformers where leakage flux leads to measurement inaccuracies, hindering precision control and data acquisition. It provides a low-frequency current transformer circuit based on hardware processing module correction. The circuit includes a current transformer (CT), whose primary winding is connected to the external circuit being measured; a resistor R connected in series in the secondary winding loop of the CT; an analog-to-digital converter (ADC) with its two input terminals connected in parallel across the resistor R; the ADC converts the analog voltage across the resistor R into a digital value; and a hardware processing module connected to the ADC. The hardware processing module parses the digital voltage value from the ADC into a current value, matches this current value to the actual value, and outputs the actual current value for use by an external receiving device.

Description

Technical Field

[0001] This utility model relates to the field of current transformer technology, and in particular to a low-frequency current transformer circuit based on hardware processing module correction. Background Technology

[0002] High precision and reliability of current measurement are crucial in fields such as power system monitoring, industrial automation control, and smart grid construction.

[0003] Although traditional low-frequency current transformer circuits can achieve current signal acquisition and conversion, they are limited by the leakage flux of low-frequency current transformers, which often leads to deviations in measurement results and makes it difficult to meet the requirements of precision control and data acquisition. Utility Model Content

[0004] This invention addresses the problem in existing technologies where low-frequency current transformers suffer from magnetic leakage, leading to measurement deviations and hindering precision control and data acquisition. It provides a low-frequency current transformer circuit based on hardware processing module correction.

[0005] The technical solution adopted in this utility model is:

[0006] A low-frequency current transformer circuit based on hardware processing module correction includes:

[0007] Current transformer (CT), the primary winding of the current transformer (CT) is connected to the external circuit being measured;

[0008] Resistor R is connected in series in the secondary winding circuit of current transformer CT;

[0009] An analog-to-digital converter (ADC) has two input terminals connected in parallel across a resistor R; the ADC converts the analog voltage across the resistor R into a digital value.

[0010] The hardware processing module is connected to the analog-to-digital converter. The hardware processing module parses the digital value of the voltage input from the analog-to-digital converter into a current value. This current value matches the actual value, and the output terminal of the hardware processing module outputs the actual current value for use by an external receiving device.

[0011] Furthermore, the hardware processing module includes:

[0012] The parsing submodule is connected to the analog-to-digital converter (ADC). It receives the voltage value from the ADC, parses the digital value of the voltage value into a current value, and outputs the current value.

[0013] The mapping submodule matches the current value output by the parsing submodule with the actual current value and outputs it for use by the external receiving device.

[0014] Furthermore, the hardware processing module is an FPGA.

[0015] Furthermore, the analog-to-digital converter and the FPGA are integrated on the same printed circuit board.

[0016] Furthermore, both the parsing submodule and the mapping submodule are internal circuits of the FPGA.

[0017] Furthermore, the hardware processing module is ZYNQ.

[0018] Furthermore, the analog-to-digital converter is integrated with the ZYNQ on the same printed circuit board.

[0019] Furthermore, both the parsing submodule and the mapping submodule are internal circuits of ZYNQ.

[0020] Furthermore, the hardware processing module is an ASIC.

[0021] Furthermore, both the parsing submodule and the mapping submodule are internal circuits of the ASIC.

[0022] The beneficial effects of this utility model are:

[0023] The current transformer circuit based on hardware processing module correction acquires the current of the circuit under test through the current transformer (CT), converts it into a voltage signal through the resistor R in the secondary circuit, then converts it into a digital signal by an analog-to-digital converter (ADC), and finally, the hardware processing module analyzes and matches the actual current value for output. This circuit integrates the ADC and the hardware processing module, effectively reducing signal transmission interference and improving conversion accuracy. The hardware processing module calculates the current value based on the digital signal and matches it to the actual value, significantly reducing measurement errors and achieving high-precision detection of the current in the circuit under test. This meets the stringent requirements for current measurement accuracy in industrial control, power monitoring, and other scenarios. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, 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.

[0025] Figure 1 This is a circuit schematic of a low-frequency current transformer that is corrected based on a hardware processing module. Detailed Implementation

[0026] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0027] The following disclosure provides many different embodiments or examples for implementing various structures of this invention. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of this invention.

[0028] The embodiments of the utility model will now be described in detail with reference to the accompanying drawings.

[0029] As attached Figure 1 As shown, the current transformer circuit based on hardware processing module correction disclosed in this embodiment includes the following components: current transformer CT, resistor R, analog-to-digital converter 1, and hardware processing module 2. In addition to the complete low-frequency current transformer circuit, a test circuit 3 and an external receiving device 4 are also provided. The effective value of the current in the test circuit 3 is a 10A sinusoidal alternating current.

[0030] External receiving device 4 receives the actual value of the current output by the low-frequency current transformer circuit.

[0031] The primary winding of the current transformer (CT) is connected to the external circuit being measured.

[0032] A resistor R is connected in series in the secondary winding circuit of the current transformer CT, and the resistance of resistor R is 100Ω.

[0033] The two input terminals of analog-to-digital converter 1 are connected in parallel across resistor R. Analog-to-digital converter 1 converts the analog voltage value into a digital value. In this embodiment, analog-to-digital converter 1 uses AD7606 analog-to-digital converter chip, whose input voltage range can be configured from -5V to 5V.

[0034] Hardware processing module 2 is connected to analog-to-digital converter 1. Hardware processing module 2 parses the digital value of the voltage input from analog-to-digital converter 1 into a current value. This current value matches the actual value, and the output of hardware processing module 2 outputs the actual current value for use by external receiving device 4. In this embodiment, hardware processing module 2 is an FPGA.

[0035] The workflow of the current transformer circuit based on hardware processing module correction disclosed in the above embodiments is as follows:

[0036] The current transformer (CT) collects the current of the circuit under test 3. The effective value of the secondary winding of the current transformer (CT) is 20mA AC. According to Ohm's law, the voltage across the resistor R is 2V.

[0037] Analog-to-digital converter 1 converts the analog voltage across resistor R into a digital value and sends it to hardware processing module 2. Hardware processing module 2 matches the digital voltage across resistor R to the actual value.

[0038] Finally, the output terminal of hardware processing module 2 outputs the actual value of the current for use by external receiving device 4.

[0039] The beneficial effects of the above technical solution are as follows: This embodiment is based on a current transformer circuit calibrated by a hardware processing module. The current transformer CT acquires the 310A sinusoidal AC current of the circuit under test. The 20mA current on the secondary side generates a 2V voltage on a 100Ω resistor R. The AD7606 analog-to-digital converter 1 converts the voltage into a digital value. Then, the FPGA hardware processing module 2 analyzes and matches the real current value, which can accurately convert the measured current into a digital signal output, meeting the requirements of the external receiving device 4 for obtaining the real current value. It has the advantages of high measurement accuracy, stable conversion, and adaptability to low-frequency current detection.

[0040] Furthermore, the hardware processing module 2 includes: a parsing submodule 21 and a mapping submodule 22.

[0041] The parsing submodule 21 is connected to the analog-to-digital converter 1, receives the voltage value input from the converter, parses the digital value of the voltage value into a current value, and outputs the current value, expressed as...

[0042] Current value = Voltage value / Resistance value of resistor R;

[0043] The mapping submodule 22 is connected to the parsing submodule 21. The mapping submodule 22 matches the actual value of the current value according to the current value output by the parsing submodule 21 and outputs it for use by the external receiving device 4.

[0044] The mapping submodule 22 matches the actual current value based on the current value output by the parsing submodule 21 using the following method:

[0045] First, the difference between the current value output by the analysis submodule 21 and the actual value is calculated. For example, if the current value output by the analysis submodule 21 is 9.9A and the actual value is 10A, the difference is 0.1A. This difference is then stored in the mapping submodule 22. When the low-frequency current transformer circuit performs its test, the current value output by the analysis submodule 21 (e.g., 8A) is added to the difference (0.1A) to obtain 8.1A. Finally, 8.1A is taken as the actual current value and output.

[0046] Furthermore, the hardware processing module 2 includes a parsing submodule 21 and a mapping submodule 22. Both the parsing submodule 21 and the mapping submodule 22 are internal circuits of the FPGA, i.e., modules developed within the FPGA. The analog-to-digital converter 1 is integrated with the FPGA on the same printed circuit board.

[0047] Furthermore, the hardware processing module 2 includes a parsing submodule 21 and a mapping submodule 22. Both the parsing submodule 21 and the mapping submodule 22 are internal circuits of the ZYNQ, meaning they are modules developed within the ZYNQ. The analog-to-digital converter 1 is integrated with the ZYNQ on the same printed circuit board.

[0048] Furthermore, the hardware processing module 2 includes a parsing submodule 21 and a mapping submodule 22. Both the parsing submodule 21 and the mapping submodule 22 are internal circuits of the ASIC, that is, modules developed within the ASIC.

[0049] The beneficial effects of the above technical solution are as follows: Through the collaborative work of the analysis submodule 21 and the mapping submodule 22, the analysis submodule 21 first accurately analyzes the current value according to the formula "current value = voltage value / resistance value R", and then the mapping submodule 22 dynamically corrects the current based on the pre-stored difference (e.g., correcting 8A to 8.1A), thereby achieving high-precision measurement of the current of the circuit under test 3. The analysis submodule 21 and the mapping submodule 22 can be developed based on the internal circuitry of FPGA, ZYNQ, or ASIC, and integrated with the analog-to-digital converter 1 on the same printed circuit board. They combine the advantages of hardware-level processing speed, stability, and integration, effectively improving measurement accuracy and are suitable for industrial control, power monitoring, and other scenarios with stringent requirements for current detection accuracy.

Claims

1. A low-frequency current transformer circuit based on hardware processing module correction, characterized in that, include: Current transformer (CT), the primary winding of the current transformer (CT) is connected to the external circuit being measured; Resistor R is connected in series in the secondary winding circuit of current transformer CT; An analog-to-digital converter (ADC) has two input terminals connected in parallel across a resistor R; the ADC converts the analog voltage across the resistor R into a digital value. The hardware processing module is connected to the analog-to-digital converter. The hardware processing module parses the digital value of the voltage input from the analog-to-digital converter into a current value. This current value matches the actual value, and the output terminal of the hardware processing module outputs the actual current value for use by an external receiving device.

2. The low-frequency current transformer circuit based on hardware processing module correction according to claim 1, characterized in that, The hardware processing module includes: The parsing submodule is connected to the analog-to-digital converter (ADC). It receives the voltage value from the ADC, parses the digital value of the voltage value into a current value, and outputs the current value. The mapping submodule matches the current value output by the parsing submodule with the actual current value and outputs it for use by the external receiving device.

3. The low-frequency current transformer circuit based on hardware processing module correction according to claim 1, characterized in that, The hardware processing module is an FPGA.

4. The low-frequency current transformer circuit based on hardware processing module correction according to claim 3, characterized in that, The analog-to-digital converter and the FPGA are integrated on the same printed circuit board.

5. The low-frequency current transformer circuit based on hardware processing module correction according to claim 3, characterized in that, Both the parsing submodule and the mapping submodule are internal circuits of the FPGA.

6. The low-frequency current transformer circuit based on hardware processing module correction according to claim 1, characterized in that, The hardware processing module is ZYNQ.

7. The low-frequency current transformer circuit based on hardware processing module correction according to claim 6, characterized in that, The analog-to-digital converter is integrated with the ZYNQ on the same printed circuit board.

8. The low-frequency current transformer circuit based on hardware processing module correction according to claim 6, characterized in that, Both the parsing submodule and the mapping submodule are internal circuits of ZYNQ.

9. The low-frequency current transformer circuit based on hardware processing module correction according to claim 1, characterized in that, The hardware processing module is an ASIC.

10. The low-frequency current transformer circuit based on hardware processing module correction according to claim 9, characterized in that, Both the parsing submodule and the mapping submodule are internal circuits of the ASIC.

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