High-frequency current sensor transmission impedance verification method and system

Abstract

The invention provides a high-frequency current sensor transmission impedance verification method and system, and the method comprises the following steps: considering periodic pulse interference, and constructing a response mathematical model of a to-be-verified high-frequency current sensor; calculating to obtain an interference compensation coefficient based on the response mathematical model; and calculating a transmission impedance curve of the to-be-verified high-frequency current sensor by using the interference compensation coefficient, and completing transmission impedance verification of the to-be-verified high-frequency current sensor. According to the technical scheme, the transmission impedance verification accuracy of the high-frequency current sensor is improved; and the accurate verification result is beneficial to improving the reliability of partial discharge monitoring, so that the safe and stable operation of a power system is ensured.

Description

Background Art

[0002] As the power system develops towards high voltage and large capacity, the accuracy and reliability of power equipment status monitoring are increasingly required. Partial discharge is one of the important factors affecting the safe operation of power equipment, and its monitoring technology has become a research hotspot in the field of power system monitoring. As an effective partial discharge monitoring tool, the accuracy of the performance of high-frequency current sensors is directly related to the accuracy of partial discharge detection.

[0003] The traditional high-frequency current sensor transmission impedance calibration method is carried out in a laboratory environment, ignoring the interference that may exist in the field environment. These interferences may come from a variety of factors such as high-frequency protection signals, carrier communications, harmonics generated in the power system, radio broadcasts, etc., which will have a significant impact on the sensor's measurement results. Therefore, the existing calibration method may not accurately reflect the performance of the sensor in a real working environment in actual applications.

[0004] In order to improve the accuracy of monitoring data, a high-frequency current sensor transmission impedance verification method that can take into account the influence of periodic pulse interference is needed. This method should be able to accurately verify the transmission impedance of the sensor in the actual working environment to ensure the reliability of the monitoring results. Summary of the invention

[0005] The present application provides a method and system for calibrating the transmission impedance of a high-frequency current sensor, which are used to accurately calibrate the transmission impedance of the sensor in a field environment with periodic pulse interference, thereby improving the accuracy of partial discharge monitoring and the safety of the power system.

[0006] In a first aspect, a method for verifying the transmission impedance of a high-frequency current sensor is provided, comprising the following steps:

[0007] Taking into account periodic pulse interference, constructing a response mathematical model of the high-frequency current sensor to be verified;

[0008] Based on the response mathematical model, an interference compensation coefficient is calculated;

[0009] The interference compensation coefficient is used to calculate the transmission impedance curve of the high-frequency current sensor to be verified, and the transmission impedance verification of the high-frequency current sensor to be verified is completed.

[0010] In the above technical scheme, by taking into account periodic pulse interference, a response mathematical model of the high-frequency current sensor to be verified is constructed; based on the response mathematical model, the interference compensation coefficient is calculated; using the interference compensation coefficient, the transmission impedance curve of the high-frequency current sensor to be verified is calculated, and the transmission impedance verification of the high-frequency current sensor to be verified is completed; the accuracy of the transmission impedance verification of the high-frequency current sensor is improved; accurate verification results help to improve the reliability of partial discharge monitoring, thereby ensuring the safe and stable operation of the power system.

[0011] In a specific embodiment, it also includes:

[0012] Generate an excitation signal and input it into the high-frequency current sensor to be calibrated.

[0013] In a specific implementation manner, the excitation signal is an excitation signal D(f0) whose output frequency is an independent variable f0.

[0014] In a specific implementation scheme, the frequency domain model J(f1) of the periodic pulse interference is:

[0015]

[0016] Where A is the amplitude of periodic pulse interference, τ is the width of pulse interference within one cycle, and f c is the center frequency of the pulse interference, and Sa is the sampling function.

[0017] In a specific implementation scheme, the mathematical model of the response of the high-frequency current sensor to be verified to the excitation signal D(f0) is:

[0018] U out (f)=|H(f)|·D(f0)·δ(f-f0)+|H(f-f1)|·J(f1)·δ(f-f1);

[0019] Among them, δ(f) is the Dirac function, J(f1) is the frequency domain model of periodic pulse interference, and H(f) is the response of the high-frequency current sensor to be verified to the excitation signal D(f0).

[0020] In a specific implementation scheme, the calculation formula of the interference compensation coefficient C is:

[0021]

[0022] Wherein, R is the outer diameter of the high-frequency current sensor coil to be calibrated, r is the inner diameter of the coil, and σ is the eccentricity of the coil.

[0023] In a specific implementation scheme, the calculation formula of the transmission impedance of the high-frequency current sensor to be verified is:

[0024]

[0025] Among them, R is the standard resistance; U R is the voltage value of the standard resistor; U out is the output voltage value of the high-frequency current sensor to be verified.

[0026] In a specific implementation manner, the frequency range of the excitation signal D(f0) is 3 MHz to 30 MHz.

[0027] In a second aspect, a high-frequency current sensor transmission impedance verification system is provided, comprising:

[0028] A signal generator, used to generate an excitation signal and input it into the high-frequency current sensor to be calibrated;

[0029] The host computer is used to detect the output voltage value of the high-frequency current sensor to be verified and complete the transmission impedance verification of the high-frequency current sensor to be verified.

[0030] In the above technical scheme, by taking into account periodic pulse interference, a response mathematical model of the high-frequency current sensor to be verified is constructed; based on the response mathematical model, the interference compensation coefficient is calculated; using the interference compensation coefficient, the transmission impedance curve of the high-frequency current sensor to be verified is calculated, and the transmission impedance verification of the high-frequency current sensor to be verified is completed; the accuracy of the transmission impedance verification of the high-frequency current sensor is improved; accurate verification results help to improve the reliability of partial discharge monitoring, thereby ensuring the safe and stable operation of the power system.

[0031] In a specific implementation scheme, the host computer includes:

[0032] A model module, used to take into account periodic pulse interference and construct a response mathematical model of the high-frequency current sensor to be verified;

[0033] A coefficient module, used for calculating an interference compensation coefficient based on the response mathematical model;

[0034] The impedance module is used to calculate the transmission impedance curve of the high-frequency current sensor to be verified by using the interference compensation coefficient, and complete the transmission impedance verification of the high-frequency current sensor to be verified. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A flowchart of a method for verifying the transmission impedance of a high-frequency current sensor provided in an embodiment of the present application;

[0036] Figure 2A structural block diagram of a host computer of a high-frequency current sensor transmission impedance calibration system provided in an embodiment of the present application;

[0037] Figure 3 A schematic diagram of a periodic pulse interference signal provided in an embodiment of the present application;

[0038] Figure 4 A structural diagram of a high-frequency current sensor transmission impedance calibration system provided in an embodiment of the present application;

[0039] Figure 5 This is a structural diagram of the sensor coil provided in an embodiment of the present application. DETAILED DESCRIPTION

[0040] The present application is further described in detail below through the accompanying drawings and embodiments. Through these descriptions, the characteristics and advantages of the present application will become clearer and more specific.

[0041] The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise noted.

[0042] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0043] To facilitate understanding of the high-frequency current sensor transmission impedance calibration method and system provided in the embodiment of the present application, its application scenario is first explained. The high-frequency current sensor transmission impedance calibration method and system provided in the embodiment of the present application are used to accurately calibrate the transmission impedance of the sensor in a field environment with periodic pulse interference, thereby improving the accuracy of partial discharge monitoring and the safety of the power system. As the power system develops towards high voltage and large capacity, the accuracy and reliability of power equipment status monitoring are increasingly required. Partial discharge is one of the important factors affecting the safe operation of power equipment, and its monitoring technology has become a research hotspot in the field of power system monitoring. As an effective partial discharge monitoring tool, the accuracy of the performance of the high-frequency current sensor is directly related to the accuracy of partial discharge detection. The traditional high-frequency current sensor transmission impedance calibration method is carried out in a laboratory environment, ignoring the interference that may exist in the field environment. These interferences may come from various factors such as high-frequency protection signals, carrier communications, harmonics generated in the power system, radio broadcasts, etc., which will have a significant impact on the measurement results of the sensor. Therefore, the existing calibration method may not accurately reflect the performance of the sensor in a real working environment in practical applications. In order to improve the accuracy of monitoring data, a high-frequency current sensor transmission impedance calibration method that can consider the influence of periodic pulse interference is needed. This method should be able to accurately calibrate the transmission impedance of the sensor in an actual working environment to ensure the reliability of the monitoring results. To this end, the embodiment of the present application provides a method and system for calibrating the transmission impedance of a high-frequency current sensor to accurately calibrate the transmission impedance of the sensor in a field environment with periodic pulse interference, thereby improving the accuracy of partial discharge monitoring and the safety of the power system. The following is a detailed description of the embodiment in conjunction with specific drawings.

[0044] refer to Figures 1 to 5 , Figure 1 A flowchart of a method for verifying the transmission impedance of a high-frequency current sensor provided in an embodiment of the present application; Figure 2 A structural block diagram of a host computer of a high-frequency current sensor transmission impedance calibration system provided in an embodiment of the present application; Figure 3 A schematic diagram of a periodic pulse interference signal provided in an embodiment of the present application; Figure 4 A structural diagram of a high-frequency current sensor transmission impedance calibration system provided in an embodiment of the present application; Figure 5 This is a structural diagram of the sensor coil provided in an embodiment of the present application.

[0045] exist Figure 1 In the embodiment of the present application, a method for verifying the transmission impedance of a high-frequency current sensor is provided, comprising the following steps:

[0046] Taking into account periodic pulse interference, constructing a response mathematical model of the high-frequency current sensor to be verified;

[0047] Based on the response mathematical model, an interference compensation coefficient is calculated;

[0048] The interference compensation coefficient is used to calculate the transmission impedance curve of the high-frequency current sensor to be verified, and the transmission impedance verification of the high-frequency current sensor to be verified is completed.

[0049] In the above technical scheme, by taking into account periodic pulse interference, a response mathematical model of the high-frequency current sensor to be verified is constructed; based on the response mathematical model, the interference compensation coefficient is calculated; using the interference compensation coefficient, the transmission impedance curve of the high-frequency current sensor to be verified is calculated, and the transmission impedance verification of the high-frequency current sensor to be verified is completed; the accuracy of the transmission impedance verification of the high-frequency current sensor is improved; accurate verification results help to improve the reliability of partial discharge monitoring, thereby ensuring the safe and stable operation of the power system.

[0050] In a specific embodiment, it also includes:

[0051] Generate an excitation signal and input it into the high-frequency current sensor to be calibrated.

[0052] In a specific implementation manner, the excitation signal is an excitation signal D(f0) whose output frequency is an independent variable f0.

[0053] In a specific implementation scheme, the frequency domain model J(f1) of the periodic pulse interference is:

[0054]

[0055] Where A is the amplitude of periodic pulse interference, τ is the width of pulse interference within one cycle, and f c is the center frequency of the pulse interference, and Sa is the sampling function.

[0056] In a specific implementation scheme, the mathematical model of the response of the high-frequency current sensor to be verified to the excitation signal D(f0) is:

[0057] U out (f)=|H(f)|·D(f0)·δ(f-f0)+|H(f-f1)|·J(f1)·δ(f-f1);

[0058] Among them, δ(f) is the Dirac function, J(f1) is the frequency domain model of periodic pulse interference, and H(f) is the response of the high-frequency current sensor to be verified to the excitation signal D(f0).

[0059] In a specific implementation scheme, the calculation formula of the interference compensation coefficient C is:

[0060]

[0061] Wherein, R is the outer diameter of the high-frequency current sensor coil to be calibrated, r is the inner diameter of the coil, and σ is the eccentricity of the coil.

[0062] In a specific implementation scheme, the calculation formula of the transmission impedance of the high-frequency current sensor to be verified is:

[0063]

[0064] Among them, R is the standard resistance; U R is the voltage value of the standard resistor; U out is the output voltage value of the high-frequency current sensor to be verified.

[0065] In a specific implementation manner, the frequency range of the excitation signal D(f0) is 3 MHz to 30 MHz.

[0066] Specifically, the specific process of the high-frequency current sensor transmission impedance verification method is as follows:

[0067] 1. Generate and output an excitation signal D(f0) with a frequency of f0 through a signal generator, and input the signal into a high-frequency current sensor; the secondary side of the high-frequency current sensor is connected to a host computer, and the host computer is used to measure the output signal U of the high-frequency current sensor at the frequency f0. out (f); The signal generator is connected in series with a standard resistor R, and the voltage U across the resistor is measured using an oscilloscope R ;

[0068] 2. Considering the periodic pulse interference in the field verification environment, the response H(f) of the high-frequency current sensor to the excitation signal D(f0) is calculated using the following formula:

[0069] U out (f)=|H(f)|·D(f0)·δ(f-f0)+|H(f-f1)|·J(f1)·δ(f-f1);

[0070] Among them, δ(f) is the Dirac function, J(f1) is the frequency domain model of periodic pulse interference,

[0071]

[0072] Where A is the amplitude of periodic pulse interference, τ is the width of pulse interference within one cycle, and f c is the center frequency of the pulse interference, Sa is the sampling function;

[0073] 3. Calculate the interference compensation coefficient C as follows:

[0074]

[0075] Where R is the outer diameter of the high-frequency current sensor coil, r is the inner diameter of the coil, and σ is the eccentricity of the coil.

[0076] 4. Use the following formula to calculate the high-frequency sensor transmission impedance:

[0077]

[0078] 5. Change the signal generator output signal frequency within the range of 3MHz to 30MHz, repeat the above steps, calculate the transmission impedance value corresponding to each frequency, and obtain the transmission impedance curve of the high-frequency current sensor to be calibrated within the frequency range.

[0079] Compared with the prior art, the advantages of this application are:

[0080] 1. By considering periodic pulse interference, the accuracy of high-frequency current sensor transmission impedance verification is improved.

[0081] 2. This method is suitable for field environments and can more truly reflect the performance of the sensor under actual working conditions.

[0082] 3. The accurate verification results of the present invention are helpful to improve the reliability of partial discharge monitoring, thereby ensuring the safe and stable operation of the power system.

[0083] exist Figures 2 to 5 In the embodiment of the present application, a high-frequency current sensor transmission impedance verification system is provided, comprising:

[0084] A signal generator, used to generate an excitation signal and input it into the high-frequency current sensor to be calibrated;

[0085] The host computer is used to detect the output voltage value of the high-frequency current sensor to be verified and complete the transmission impedance verification of the high-frequency current sensor to be verified.

[0086] In the above technical scheme, by taking into account periodic pulse interference, a response mathematical model of the high-frequency current sensor to be verified is constructed; based on the response mathematical model, the interference compensation coefficient is calculated; using the interference compensation coefficient, the transmission impedance curve of the high-frequency current sensor to be verified is calculated, and the transmission impedance verification of the high-frequency current sensor to be verified is completed; the accuracy of the transmission impedance verification of the high-frequency current sensor is improved; accurate verification results help to improve the reliability of partial discharge monitoring, thereby ensuring the safe and stable operation of the power system.

[0087] In a specific implementation scheme, the host computer includes:

[0088] A model module, used to take into account periodic pulse interference and construct a response mathematical model of the high-frequency current sensor to be verified;

[0089] A coefficient module, used for calculating an interference compensation coefficient based on the response mathematical model;

[0090] The impedance module is used to calculate the transmission impedance curve of the high-frequency current sensor to be verified by using the interference compensation coefficient, and complete the transmission impedance verification of the high-frequency current sensor to be verified.

[0091] Those skilled in the art will appreciate that the present application may be implemented as a system, method or computer program product.

[0092] Therefore, the present disclosure may be specifically implemented in the following forms, namely: it may be completely hardware, it may be completely software (including firmware, resident software, microcode, etc.), or it may be a combination of hardware and software, generally referred to herein as a "circuit", "module" or "system". In addition, in some embodiments, the present application may also be implemented in the form of a computer program product in one or more computer-readable media, and the computer-readable medium may contain computer-readable program code.

[0093] Any combination of one or more computer-readable media can be used. Computer-readable media can be computer-readable signal media or computer-readable storage media. Computer-readable storage media can be, for example, but not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or devices, or any combination of the above. More specific examples (non-exhaustive list) of computer-readable storage media include: electrical connections with one or more wires, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above. In this document, computer-readable storage media can be any tangible medium containing or storing a program, which can be used by an instruction execution system, device or device or used in combination with it.

[0094] Although the embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art can change, modify, replace and modify the above embodiments within the scope of the present application. On this basis, a variety of replacements and improvements can be made to the present application, all of which fall within the scope of protection of the present application.

Claims

1. A method for verifying the transmission impedance of a high-frequency current sensor, characterized in that: The following steps are involved: Taking into account periodic pulse interference, constructing a response mathematical model of the high-frequency current sensor to be verified; Based on the response mathematical model, an interference compensation coefficient is calculated; The interference compensation coefficient is used to calculate the transmission impedance curve of the high-frequency current sensor to be verified, and the transmission impedance verification of the high-frequency current sensor to be verified is completed.

2. The high-frequency current sensor transmission impedance calibration method according to claim 1, characterized in that: Also includes: Generate an excitation signal and input it into the high-frequency current sensor to be calibrated.

3. The high-frequency current sensor transmission impedance calibration method according to claim 2, characterized in that: The excitation signal is an excitation signal D(f0) whose output frequency is an independent variable f0.

4. The high-frequency current sensor transmission impedance calibration method according to claim 3, characterized in that: The frequency domain model J(f1) of the periodic pulse interference is: Where A is the amplitude of periodic pulse interference, τ is the width of pulse interference within one cycle, and f c is the center frequency of the pulse interference, and Sa is the sampling function.

5. The high-frequency current sensor transmission impedance calibration method according to claim 4, characterized in that: The mathematical model of the response of the high-frequency current sensor to be verified to the excitation signal D(f0) is: U out (f)=|H(f)|·D(f0)·δ(f-f0)+|H(f-f1)|·J(f1)·δ(f-f1); Among them, δ(f) is the Dirac function, J(f1) is the frequency domain model of periodic pulse interference, and H(f) is the response of the high-frequency current sensor to be verified to the excitation signal D(f0).

6. The high-frequency current sensor transmission impedance calibration method according to claim 5, characterized in that: The calculation formula of the interference compensation coefficient C is: Wherein, R is the outer diameter of the high-frequency current sensor coil to be calibrated, r is the inner diameter of the coil, and σ is the eccentricity of the coil.

7. The high-frequency current sensor transmission impedance calibration method according to claim 6, characterized in that: The calculation formula of the transmission impedance of the high-frequency current sensor to be verified is: Among them, R is the standard resistance; U R is the voltage value of the standard resistor; U out is the output voltage value of the high-frequency current sensor to be verified.

8. The high-frequency current sensor transmission impedance calibration method according to claim 7, characterized in that: The frequency range of the excitation signal D(f0) is 3 MHz to 30 MHz.

9. A high-frequency current sensor transmission impedance calibration system, characterized in that: include: A signal generator, used to generate an excitation signal and input it into the high-frequency current sensor to be calibrated; The host computer is used to detect the output voltage value of the high-frequency current sensor to be verified and complete the transmission impedance verification of the high-frequency current sensor to be verified.

10. The high-frequency current sensor transmission impedance calibration system according to claim 9, characterized in that: The host computer comprises: A model module, used to take into account periodic pulse interference and construct a response mathematical model of the high-frequency current sensor to be verified; A coefficient module, used for calculating an interference compensation coefficient based on the response mathematical model; The impedance module is used to calculate the transmission impedance curve of the high-frequency current sensor to be verified by using the interference compensation coefficient, and complete the transmission impedance verification of the high-frequency current sensor to be verified.

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