Broadband voltage error measurement system and method

Abstract

The invention discloses a broadband voltage error measurement system and system, and the system is characterized in that a differential voltage signal measurement module carries out the differential operation of an input standard signal and a measured signal, and obtains a difference signal; the difference value signal is input into a conditioning link composed of a zero-flux-current induction unit of the isolation feedback module and a low-noise amplification circuit, and a difference value analog signal is output to the data acquisition module through the conditioning link; the standard signal measurement module is used for reducing the standard signal according to a preset proportion and outputting the reduced standard signal to the data acquisition module; the data acquisition module is used for converting the difference analog signal and the standard signal into a difference digital signal and a standard digital signal, and outputting the difference digital signal and the standard digital signal to the error analysis module; the error analysis module calculates a voltage error in a broadband range through a preset algorithm based on the difference digital signal and the standard digital signal, and generates an error characteristic curve.

Description

Technical Field

[0001] This invention relates to the field of AC voltage testing technology, and more specifically, to a broadband voltage error measurement system and method. Background Technology

[0002] With the development of new power systems and the large-scale integration of various power electronic devices and distributed energy sources into the power grid, power quality issues are becoming increasingly prominent. Voltage signals are affected by various factors such as harmonics, interharmonics, and transient impacts during power grid operation, exhibiting new characteristics such as wide frequency spectrum and rapid dynamic changes. Traditional voltage measurement methods are mostly centered on the power frequency, focusing on the measurement of the fundamental frequency and low-order harmonics. Their response capability to high-frequency harmonics and wideband signals is limited, making it difficult to meet the current power grid's demand for high-precision, wideband voltage measurement.

[0003] In practical applications, accurate assessment of voltage measurement errors is crucial for power quality analysis, relay protection, fault diagnosis, and equipment health monitoring. However, existing measurement systems often suffer from uneven amplitude response, inconsistent phase delay, and insufficient anti-interference capabilities over a wide frequency range, affecting the accuracy and reliability of measurement results. Especially in complex power grid environments with high penetration of new energy sources and flexible interconnection, the frequency domain components of voltage signals are richer, making traditional error measurement methods inadequate.

[0004] Currently, research on broadband voltage measurement is gradually unfolding both domestically and internationally, and related standards and testing methods are constantly being improved. However, existing technologies mostly rely on calibration and measurement of single frequency points or narrowband signals, lacking systematic analysis and compensation for errors over a wide bandwidth. While some methods can achieve error measurement within a certain range, they still have shortcomings in terms of signal bandwidth, measurement accuracy, and real-time performance, making it difficult to meet the actual needs of new power systems for high-precision voltage signal measurement across multiple frequency bands and scenarios.

[0005] Therefore, there is an urgent need to develop a voltage error measurement method and system that can cover a wide frequency band and possess high precision and real-time performance, in order to improve the measurement technology level of power systems and ensure the safe and stable operation of the power grid. This has significant practical implications and application value for promoting the healthy development of new power systems such as smart grids and the energy internet. Summary of the Invention

[0006] The present invention provides a wideband voltage error measurement system and method to solve the problem of how to accurately measure wideband voltage signals.

[0007] To address the aforementioned problems, this invention provides a wideband voltage error measurement system, comprising: a differential pressure signal measurement module, an isolation feedback module, a standard signal measurement module, a data acquisition module, and an error analysis module;

[0008] The differential pressure signal measurement module obtains a difference signal by performing differential operations on the input standard signal and the measured signal; the difference signal is input to a conditioning link composed of the zero flux current sensing unit of the isolation feedback module and a low noise amplifier circuit, and the differential analog signal is output to the data acquisition module via the conditioning link;

[0009] The standard signal measurement module is used to reduce the standard signal by a preset ratio and output the reduced standard signal to the data acquisition module;

[0010] The data acquisition module is used to convert the difference analog signal and the standard signal into a difference digital signal and a standard digital signal, and output the difference digital signal and the standard digital signal to the error analysis module;

[0011] The error analysis module calculates the voltage error over a wide frequency band based on the difference digital signal and the standard digital signal using a preset algorithm, and generates an error characteristic curve.

[0012] Preferably, the differential pressure signal measurement module is a differential voltage divider structure, including a low-temperature drift precision resistor, the resistance deviation of which is controlled within ±0.01%.

[0013] Preferably, the zero flux current sensing unit of the isolation feedback module is disposed at the output end of the differential pressure signal measurement module, and the direction of the sensing coil of the zero flux current sensing unit is consistent with the direction of the magnetic field of the input differential signal.

[0014] Preferably, the zero flux current sensing unit and the low noise amplifier circuit are connected in series to form a conditioning link;

[0015] The input impedance of the low-noise amplifier circuit is matched with the output impedance of the differential pressure signal measurement module; the gain of the low-noise amplifier circuit is set by an externally adjustable resistor.

[0016] Preferably, the error analysis module includes a program storage area and a data cache area;

[0017] The program storage area is used to store the error analysis algorithm, which is a fast Fourier transform algorithm.

[0018] The data buffer is used to store the difference digital signal and the standard digital signal.

[0019] According to another aspect of the present invention, the present invention provides a method for wideband voltage error measurement based on the above-described system, the method comprising:

[0020] The differential pressure signal measurement module performs differential calculations on the input standard signal and the measured signal to obtain the difference signal; the difference signal is then input to the conditioning link composed of the zero flux current sensing unit of the isolation feedback module and the low noise amplifier circuit, and the differential analog signal is output to the data acquisition module via the conditioning link;

[0021] The standard signal is reduced by a preset ratio using the standard signal measurement module, and the reduced standard signal is output to the data acquisition module.

[0022] The data acquisition module converts the difference analog signal and the standard signal into a difference digital signal and a standard digital signal, and outputs the difference digital signal and the standard digital signal to the error analysis module.

[0023] The error analysis module calculates the voltage error over a wide frequency band based on the difference digital signal and the standard digital signal using a preset algorithm, and generates an error characteristic curve.

[0024] Preferably, the differential pressure signal measurement module is a differential voltage divider structure, including a low-temperature drift precision resistor, the resistance deviation of which is controlled within ±0.01%.

[0025] Preferably, the zero flux current sensing unit of the isolation feedback module is disposed at the output end of the differential pressure signal measurement module, and the direction of the sensing coil of the zero flux current sensing unit is consistent with the direction of the magnetic field of the input differential signal.

[0026] Preferably, the zero flux current sensing unit and the low noise amplifier circuit are connected in series to form a conditioning link;

[0027] The input impedance of the low-noise amplifier circuit is matched with the output impedance of the differential pressure signal measurement module; the gain of the low-noise amplifier circuit is set by an externally adjustable resistor.

[0028] Preferably, the error analysis module includes a program storage area and a data cache area;

[0029] The program storage area is used to store the error analysis algorithm, which is a fast Fourier transform algorithm.

[0030] The data buffer is used to store the difference digital signal and the standard digital signal.

[0031] This invention provides a wideband voltage error measurement system, comprising: a differential pressure signal measurement module, an isolation feedback module, a standard signal measurement module, a data acquisition module, and an error analysis module. The differential pressure signal measurement module performs differential operations on the input standard signal and the measured signal to obtain a difference signal. The difference signal is input to a conditioning link composed of a zero-flux current sensing unit and a low-noise amplifier circuit of the isolation feedback module, and outputs a differential analog signal to the data acquisition module via the conditioning link. The standard signal measurement module reduces the standard signal by a preset ratio and outputs the reduced standard signal to the data acquisition module. The data acquisition module converts the differential analog signal and the standard signal into a differential digital signal and a standard digital signal, and outputs these two signals to the error analysis module. The error analysis module calculates the voltage error over a wide bandwidth based on the differential digital signal and the standard digital signal using a preset algorithm and generates an error characteristic curve. This invention improves the anti-interference capability of low-amplitude signals through a differential voltage divider structure and a zero-flux current sensing unit. It combines a low-noise amplifier circuit and a high-speed analog-to-digital converter for accurate signal acquisition and utilizes a fast Fourier transform algorithm for frequency domain decomposition and error calculation. This invention addresses the performance limitations of traditional equipment under high-frequency and low-amplitude signal conditions, significantly improving measurement accuracy and reliability, and providing assurance for the accurate measurement of wideband voltage signals. Attached Figure Description

[0032] Exemplary embodiments of the present invention can be more fully understood by referring to the following figures:

[0033] Figure 1 A structural diagram of a broadband voltage error measurement system according to a preferred embodiment of the present invention; and

[0034] Figure 2 This is a flowchart of a broadband voltage error measurement method according to a preferred embodiment of the present invention. Detailed Implementation

[0035] Exemplary embodiments of the invention will now be described with reference to the accompanying drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0036] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0037] Figure 1 This is a structural diagram of a broadband voltage error measurement system according to a preferred embodiment of the present invention.

[0038] This invention proposes a wideband voltage error measurement system. By introducing a multi-level signal conditioning and dynamic compensation mechanism, combined with high-precision digital acquisition and real-time error analysis technology, it can achieve accurate measurement and error correction of wideband voltage signals, while reducing the performance limitations of traditional measurement equipment in high-frequency bands and low-amplitude signals.

[0039] This invention proposes a wideband voltage error measurement system, comprising: a differential pressure signal measurement module, which adopts a differential voltage divider structure and consists of multiple precision resistors, respectively connected to a standard signal and the signal under test, and obtains the minute difference signal between the two through differential operation; an isolation feedback module, which includes a current sensing unit based on the zero flux principle and a set of low-noise amplifier circuits, used to perform level conversion and gain adjustment on the difference signal; a standard signal measurement module, used to measure a standard wideband voltage signal for error calculation; a data acquisition module, which integrates a high-speed analog-to-digital converter, receives the analog signal output from the signal conditioning module through a synchronous sampling interface, and converts it into a digital signal; and an error analysis module, which consists of a high-performance digital signal processor with a built-in fast Fourier transform algorithm, used to perform frequency domain decomposition and error calculation on the acquired digital signal.

[0040] This invention provides a system capable of accurately measuring wideband voltage signals. By introducing a differential voltage divider structure and a zero-flux current sensing unit, it solves the problem that traditional measuring equipment is susceptible to interference under low-amplitude signals. At the same time, it utilizes a low-noise amplifier circuit and a high-speed analog-to-digital converter to achieve accurate capture and digital processing of wideband signals.

[0041] This invention provides a wideband voltage error measurement system, which includes: a differential pressure signal measurement module, an isolation feedback module, a standard signal measurement module, a data acquisition module, and an error analysis module;

[0042] The differential pressure signal measurement module obtains the difference signal by performing differential operation on the input standard signal and the measured signal; the difference signal is input to the conditioning link composed of the zero flux current sensing unit of the isolation feedback module and the low noise amplifier circuit, and the differential analog signal is output to the data acquisition module through the conditioning link;

[0043] The standard signal measurement module is used to reduce the standard signal by a preset ratio and output the reduced standard signal to the data acquisition module;

[0044] The data acquisition module is used to convert the difference analog signal and the standard signal into the difference digital signal and the standard digital signal, and output the difference digital signal and the standard digital signal to the error analysis module;

[0045] The error analysis module calculates the voltage error over a wide frequency band based on the difference digital signal and the standard digital signal using a preset algorithm, and generates an error characteristic curve.

[0046] Preferably, the differential pressure signal measurement module is a differential voltage divider structure, including a low-temperature drift precision resistor, the resistance deviation of which is controlled within ±0.01%.

[0047] To further improve the stability and reliability of the system, the differential voltage divider structure of the differential pressure signal measurement module is made of low-temperature drift precision resistors, with resistance deviation controlled within ±0.01% to ensure the accuracy of differential signal extraction. The low-noise amplifier circuit is built using an instrumentation amplifier, whose input impedance is matched to the output impedance of the signal extraction module, thereby reducing signal reflection and distortion. The gain of the amplifier circuit is set by an external adjustable resistor, and high-frequency noise is suppressed through a multi-stage filtering network to improve signal quality.

[0048] Preferably, the zero flux current sensing unit of the isolation feedback module is located at the output end of the differential pressure signal measurement module, and the direction of the sensing coil of the zero flux current sensing unit is consistent with the direction of the magnetic field of the input differential signal.

[0049] Preferably, the zero flux current sensing unit and the low noise amplifier circuit are connected in series to form a conditioning link;

[0050] The input impedance of the low-noise amplifier circuit is matched with the output impedance of the differential pressure signal measurement module; the gain of the low-noise amplifier circuit is set by an externally adjustable resistor.

[0051] In the isolated feedback module of this invention, the zero-flux current sensing unit is installed at the output end of the signal extraction module and connected to the device housing via a fixed bracket. The direction of its sensing coil is aligned with the magnetic field direction of the input signal to maximize sensing efficiency. The low-noise amplifier circuit is directly soldered onto a multilayer printed circuit board and connected in series with the output end of the zero-flux current sensing unit, forming a complete signal conditioning link. This link adjusts the original signal to an amplitude range suitable for the input of the high-speed analog-to-digital converter through scaling and noise suppression processing.

[0052] Preferably, the error analysis module includes a program storage area and a data cache area;

[0053] The program storage area is used to store the error analysis algorithm, which is the Fast Fourier Transform algorithm;

[0054] The data buffer is used to store the difference digital signal and the standard digital signal.

[0055] The broadband voltage error measurement system of this invention achieves accurate measurement and error correction of broadband voltage signals through the coordinated operation of multiple modules. The following description, in conjunction with the appendix... Figure 1 The accompanying reference numerals are explained in detail.

[0056] The overall system structure of the present invention is as follows: Figure 1 As shown, it includes a differential pressure signal measurement module 1, an isolation feedback module 2, a standard signal measurement module 3, a data acquisition module 4, and an error analysis module 5.

[0057] The differential pressure signal measurement module 1 employs a differential voltage divider structure composed of multiple low-temperature drift precision resistors, with their resistance deviation controlled within ±0.01% to ensure the accuracy of differential signal extraction. These resistors are respectively connected to the standard signal and the signal under test, and the minute difference signal between the two is obtained through differential operation.

[0058] The output of the differential pressure signal measurement module 1 is connected to the isolation feedback module 2, which includes a zero-flux current sensing unit 2-1 and a low-noise amplifier circuit 2-2. The zero-flux current sensing unit 2-1 is mounted on the output of the differential pressure signal measurement module 1 and connected to the device housing via a mounting bracket. Its sensing coil is aligned with the magnetic field direction of the input signal to maximize sensing efficiency. The low-noise amplifier circuit 2-2 is directly soldered onto a multilayer printed circuit board and connected in series with the output of the zero-flux current sensing unit 2-1 to form a complete signal conditioning link. The low-noise amplifier circuit 2-2 uses an instrumentation amplifier, and its input impedance is matched to the output impedance of the differential pressure signal measurement module 1 to reduce signal distortion. The gain of the amplifier circuit is set by an external adjustable resistor, and a multi-stage filtering network is used to suppress high-frequency noise and improve signal quality.

[0059] The standard signal measurement module 3 uses the principle of electromagnetic induction to precisely reduce the standard signal according to a certain ratio. The output terminals of the standard signal measurement module 3 and the isolation feedback module 2 are connected to the data acquisition module 4.

[0060] The data acquisition module 4 integrates a high-speed analog-to-digital converter (ADC) that receives the analog signal output from the isolation feedback module 2 via a synchronous sampling interface and converts it into a digital signal. The output of the data acquisition module 4 is connected to the error analysis module 5. The internal memory of the error analysis module 5 is divided into a program storage area and a data buffer area. The program storage area stores the error analysis algorithm and control logic, while the data buffer area temporarily stores the real-time acquired signal data. A timer interrupt mechanism triggers the signal acquisition operation, and the acquired data is sequentially sent to the high-speed ADC for digitization. When calculating the error value, a preset fast Fourier transform algorithm is called, combining the sampled current and voltage values ​​to derive the error characteristic curve of the wideband signal.

[0061] This invention constructs a complete broadband voltage error measurement system by introducing a differential pressure signal measurement module 1, an isolation feedback module 2, a standard signal measurement module 3, a data acquisition module 4, and an error analysis module 5. The modules work collaboratively through clear connections and optimized techniques, not only solving the performance limitations of traditional measurement equipment under high-frequency and low-amplitude signals, but also significantly improving measurement accuracy and data transmission reliability, providing strong support for the accurate measurement of broadband voltage signals.

[0062] The digital signal processor (DSP) of this invention's error analysis module has a built-in dedicated mathematical operation unit, enabling it to quickly execute complex numerical calculations. Its internal memory is divided into a program storage area and a data buffer area. The program storage area stores the error analysis algorithm and control logic, while the data buffer area temporarily stores real-time acquired signal data. The DSP triggers signal acquisition operations through a timer interrupt mechanism and sequentially sends the acquired data to a high-speed analog-to-digital converter for digitization. When calculating the error value, the DSP calls a preset Fast Fourier Transform algorithm, combining the sampled current and voltage values ​​to derive the error characteristic curve of the broadband signal.

[0063] This invention constructs a complete broadband voltage error measurement system by introducing a differential pressure signal measurement module, an isolation feedback module, a standard signal measurement module, a data acquisition module, and an error analysis module. The modules work collaboratively through clear connections and optimized techniques, not only solving the performance limitations of traditional measurement equipment under high-frequency and low-amplitude signals, but also significantly improving measurement accuracy and data transmission reliability, providing strong support for the accurate measurement of broadband voltage signals.

[0064] Figure 2 This is a flowchart of a broadband voltage error measurement method according to a preferred embodiment of the present invention.

[0065] like Figure 2 As shown, the present invention provides a method for wideband voltage error measurement based on the system of claim 1, the method comprising:

[0066] Step 201: Perform differential operation on the input standard signal and the measured signal through the differential pressure signal measurement module to obtain the difference signal; input the difference signal to the conditioning link composed of the zero flux current sensing unit of the isolation feedback module and the low noise amplifier circuit, and output the difference analog signal to the data acquisition module through the conditioning link;

[0067] Step 202: The standard signal is reduced to a preset ratio using the standard signal measurement module, and the reduced standard signal is output to the data acquisition module;

[0068] Step 203: The data acquisition module converts the difference analog signal and the standard signal into a difference digital signal and a standard digital signal, and outputs the difference digital signal and the standard digital signal to the error analysis module;

[0069] Step 204: The error analysis module calculates the voltage error over a wide frequency band based on the difference digital signal and the standard digital signal using a preset algorithm, and generates an error characteristic curve.

[0070] Preferably, the differential pressure signal measurement module is a differential voltage divider structure, including a low-temperature drift precision resistor, the resistance deviation of which is controlled within ±0.01%.

[0071] Preferably, the zero flux current sensing unit of the isolation feedback module is located at the output end of the differential pressure signal measurement module, and the direction of the sensing coil of the zero flux current sensing unit is consistent with the direction of the magnetic field of the input differential signal.

[0072] Preferably, the zero flux current sensing unit and the low noise amplifier circuit are connected in series to form a conditioning link;

[0073] The input impedance of the low-noise amplifier circuit is matched with the output impedance of the differential pressure signal measurement module; the gain of the low-noise amplifier circuit is set by an externally adjustable resistor.

[0074] Preferably, the error analysis module includes a program storage area and a data cache area;

[0075] The program storage area is used to store the error analysis algorithm, which is the Fast Fourier Transform algorithm;

[0076] The data buffer is used to store the difference digital signal and the standard digital signal.

[0077] The broadband voltage error measurement method of the preferred embodiment of the present invention corresponds to the broadband voltage error measurement system of another preferred embodiment of the present invention, and will not be described again here.

[0078] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of the present invention can be implemented using various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0079] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0080] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0081] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0082] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the invention.

[0083] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

[0084] The invention has been described with reference to a few embodiments. However, as will be known to those skilled in the art, and as defined in the appended claims, other embodiments besides those disclosed above fall equivalently within the scope of the invention.

[0085] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the art, unless otherwise expressly defined herein. All references to “a / the / the [device, component, etc.]” ​​are openly interpreted as at least one instance of said device, component, etc., unless otherwise expressly stated. The steps of any method disclosed herein need not be performed in the exact order disclosed unless explicitly stated otherwise.

Claims

1. A wideband voltage error measurement system, the system comprising: Differential pressure signal measurement module, isolation feedback module, standard signal measurement module, data acquisition module, and error analysis module; The differential pressure signal measurement module obtains a difference signal by performing differential operation on the input standard signal and the measured signal; the difference signal is input to a conditioning link composed of the zero flux current sensing unit of the isolation feedback module and a low noise amplifier circuit, and the differential analog signal is output to the data acquisition module via the conditioning link; The standard signal measurement module is used to reduce the standard signal by a preset ratio and output the reduced standard signal to the data acquisition module; The data acquisition module is used to convert the difference analog signal and the standard signal into a difference digital signal and a standard digital signal, and output the difference digital signal and the standard digital signal to the error analysis module; The error analysis module calculates the voltage error over a wide frequency band based on the difference digital signal and the standard digital signal using a preset algorithm, and generates an error characteristic curve.

2. The system according to claim 1, wherein the differential pressure signal measurement module is a differential voltage divider structure, including a low-temperature drift precision resistor, wherein the resistance deviation of the low-temperature drift precision resistor is controlled within ±0.01%.

3. In the system according to claim 1, the zero flux current sensing unit of the isolation feedback module is disposed at the output end of the differential pressure signal measurement module, and the direction of the sensing coil of the zero flux current sensing unit is consistent with the direction of the magnetic field of the input differential signal.

4. In the system according to claim 1, the zero flux current sensing unit and the low noise amplifier circuit are connected in series to form a conditioning link; The input impedance of the low-noise amplifier circuit is matched with the output impedance of the differential pressure signal measurement module; the gain of the low-noise amplifier circuit is set by an externally adjustable resistor.

5. The system according to claim 1, wherein the error analysis module includes a program storage area and a data cache area; The program storage area is used to store the error analysis algorithm, which is a fast Fourier transform algorithm. The data buffer is used to store the difference digital signal and the standard digital signal.

6. A method for wideband voltage error measurement based on the system of claim 1, the method comprising: The differential pressure signal measurement module performs differential calculations on the input standard signal and the measured signal to obtain the difference signal. The difference signal is input to the conditioning link consisting of the zero flux current sensing unit of the isolation feedback module and the low noise amplifier circuit, and the difference analog signal is output to the data acquisition module via the conditioning link; The standard signal is reduced by a preset ratio using the standard signal measurement module, and the reduced standard signal is output to the data acquisition module. The data acquisition module converts the difference analog signal and the standard signal into a difference digital signal and a standard digital signal, and outputs the difference digital signal and the standard digital signal to the error analysis module. The error analysis module calculates the voltage error over a wide frequency band based on the difference digital signal and the standard digital signal using a preset algorithm, and generates an error characteristic curve.

7. The method according to claim 6, wherein the differential pressure signal measurement module is a differential voltage divider structure, including a low-temperature drift precision resistor, and the resistance deviation of the low-temperature drift precision resistor is controlled within ±0.01%.

8. The method according to claim 6, wherein the zero flux current sensing unit of the isolation feedback module is disposed at the output terminal of the differential pressure signal measurement module, and the direction of the sensing coil of the zero flux current sensing unit is consistent with the direction of the magnetic field of the input differential signal.

9. The method according to claim 6, wherein the zero flux current sensing unit and the low noise amplifier circuit are connected in series to form a conditioning link; The input impedance of the low-noise amplifier circuit is matched with the output impedance of the differential pressure signal measurement module; the gain of the low-noise amplifier circuit is set by an externally adjustable resistor.

10. The method according to claim 6, wherein the error analysis module includes a program storage area and a data cache area; The program storage area is used to store the error analysis algorithm, which is a fast Fourier transform algorithm. The data buffer is used to store the difference digital signal and the standard digital signal.

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