A method for constructing a simulation antenna of a UHF sensor

Abstract

The application provides a construction method of a simulation antenna of a very high frequency sensor, which comprises the following steps: establishing a geometric model of a simulation antenna corresponding to an entity very high frequency sensor antenna; constructing an equivalent circuit model of a lumped parameter element of the simulation antenna, the lumped parameter element being connected with the geometric model; obtaining geometric parameters of the geometric model; determining initial parameters of the equivalent circuit model based on input impedance parameters of the entity very high frequency sensor antenna; adopting a simulation partial discharge source to emit a simulation partial discharge pulse current corresponding to an actual partial discharge signal, comparing a simulation signal obtained by the simulation antenna with a measured signal measured by the entity very high frequency sensor antenna, and adjusting the equivalent circuit model according to a comparison result, so that the simulation signal is consistent with the measured signal.

Description

Technical Field

[0001] This invention relates to a simulation method, and more particularly to a simulation method for a signal sensor. Background Technology

[0002] The damage caused by partial discharge accumulates gradually, which can reduce the insulation performance of electrical equipment and cause malfunctions. Therefore, the detection of partial discharge plays an important role in monitoring the insulation status of electrical equipment.

[0003] The ultra-high frequency signal generated by partial discharge is extremely high and can radiate outside the electrical equipment. Therefore, the ultra-high frequency method has been widely used in the detection of partial discharge.

[0004] However, existing partial discharge detection methods mostly use physical ultra-high frequency sensor antennas to detect partial discharge signals. Due to physical limitations, this somewhat restricts the research, application, and development of partial discharge detection methods.

[0005] Therefore, it is desirable to provide a simulated UHF sensor antenna. The design requirements for UHF sensor antennas are high gain, wide bandwidth, and small size. However, due to the fact that the UHF sensor antennas used in practice are not made of ideal materials, and due to factors such as the shape and size limitations of the antenna, there is a large error between the received measured signal and the simulation results.

[0006] Based on this, it is hoped that a high-precision UHF sensor simulation antenna can be provided. Summary of the Invention

[0007] The purpose of this invention is to provide a method for constructing a simulated UHF sensor antenna. Based on the measured UHF signal obtained from a physical UHF sensor antenna, as well as the actual working principle and parameters of the physical UHF sensor antenna, a geometric model is established, and this model is combined with the lumped parameter circuit elements of the equivalent circuit in the time domain to obtain a simulation model of the UHF sensor antenna, thereby improving the simulation accuracy.

[0008] In accordance with the aforementioned objective, this invention proposes a method for constructing a UHF sensor simulation antenna, comprising the following steps:

[0009] Establish a geometric model of the simulated antenna corresponding to the physical UHF sensor antenna;

[0010] Construct an equivalent circuit model of the lumped parameter element of the simulated antenna, wherein the lumped parameter element is connected to the geometric model;

[0011] Obtain the geometric parameters of the geometric model; determine the initial parameters of the equivalent circuit model based on the input impedance parameters of the physical UHF sensor antenna;

[0012] A simulated partial discharge pulse current corresponding to the actual partial discharge signal is generated by a simulated partial discharge power supply. The simulated signal obtained by the simulated antenna is compared with the measured signal measured by the physical UHF sensor antenna. Based on the comparison results, the parameters of the equivalent circuit model are adjusted to make the simulated signal match the measured signal.

[0013] In this invention, firstly, a geometric model of the simulated antenna is established based on the physical UHF sensor antenna. Then, the geometric parameters of the geometric model and the initial parameters of the equivalent circuit model are determined. Next, the measured pulse current signal is input into the simulated partial discharge power supply, and the circuit parameters of the equivalent circuit model are finely adjusted. Finally, the simulated antenna is obtained.

[0014] Furthermore, in the method for constructing a UHF sensor simulation antenna according to the present invention, the physical UHF sensor antenna is a dipole antenna.

[0015] Furthermore, in the method for constructing an ultra-high frequency sensor simulation antenna according to the present invention, the dipole antenna is a butterfly antenna.

[0016] Furthermore, in the method for constructing the UHF sensor simulation antenna described in this invention, the geometric parameters of the geometric model corresponding to the butterfly antenna include: the arm length of the butterfly antenna and the base length of the butterfly antenna.

[0017] Furthermore, in the method for constructing the UHF sensor simulation antenna described in this invention, constructing the equivalent circuit model of the lumped parameter element specifically includes: using a reactive element and an LRC parallel resonant circuit in series to form the equivalent circuit model.

[0018] Furthermore, in the method for constructing an ultra-high frequency sensor simulation antenna according to the present invention, the LRC parallel resonant circuit includes a first capacitor, a first inductor, and a first resistor connected in parallel with each other.

[0019] Furthermore, in the method for constructing the UHF sensor simulation antenna described in this invention, calculating the geometric parameters of the simulation antenna geometric model specifically includes: selecting the resonant frequency of the antenna based on the frequency of the UHF electromagnetic wave radiated by partial discharge, and calculating the required geometric parameters based on the resonant frequency.

[0020] Furthermore, in the method for constructing the UHF sensor simulation antenna described in this invention, the input impedance parameter of the physical UHF sensor antenna is obtained based on the ratio between the voltage value measured by the physical UHF sensor antenna and the pulse current.

[0021] The method for constructing an ultra-high frequency sensor simulation antenna according to the present invention has the following beneficial effects:

[0022] The method for constructing a UHF sensor simulation antenna described in this invention is based on the measured UHF signal obtained from a physical UHF sensor antenna, as well as the actual working principle and parameters of the physical UHF sensor antenna. A geometric model is established, and it is combined with the lumped parameter element circuit of the equivalent circuit in the time domain to obtain a simulation model of the UHF sensor antenna, thereby improving the simulation accuracy. Attached Figure Description

[0023] Figure 1 This is a flowchart illustrating the steps of one embodiment of the method for constructing a UHF sensor simulation antenna according to the present invention.

[0024] Figure 2 The diagram exemplarily shows a top view of the geometric model established in one embodiment of the method for constructing a UHF sensor simulation antenna according to the present invention.

[0025] Figure 3 A side view of the geometric model established in one embodiment of the method for constructing the ultra-high frequency sensor simulation antenna according to the present invention is shown as an example.

[0026] Figure 4 The diagram shows the equivalent circuit model of the lumped parameter elements of the simulated antenna constructed using the UHF sensor simulation antenna construction method described in this invention, in one embodiment.

[0027] Figure 5 The actual current signal of the partial discharge obtained during the specific verification process is shown.

[0028] Figure 6 The actual ultra-high frequency signal of the partial discharge obtained during the specific verification process is shown.

[0029] Figure 7 The comparison between the actual UHF signal of a partial discharge and the simulated signal obtained by the simulated antenna is shown. Detailed Implementation

[0030] The following will further explain and illustrate the construction method of the ultra-high frequency sensor simulation antenna of the present invention with reference to the accompanying drawings and specific embodiments. However, this detailed description does not constitute a limitation of the present invention.

[0031] Figure 1 This is a flowchart illustrating the steps of one embodiment of the method for constructing a UHF sensor simulation antenna according to the present invention.

[0032] like Figure 1 As shown, in this embodiment, the method for constructing an ultra-high frequency sensor simulation antenna may include the following steps:

[0033] 100: Establish a geometric model of the simulated antenna corresponding to the physical UHF sensor antenna in the electromagnetic wave simulation software.

[0034] In some more specific implementations, the geometric model can be built using Remcom's XFDTD 7.3.0 software.

[0035] In some more specific implementations, a butterfly antenna can be established as follows: Figure 2 and Figure 3 The geometric model shown is as follows. The material of the butterfly antenna can be set as an ideal copper conductor, considered as a series connection of a capacitor and an inductor. The two arms of the butterfly antenna are connected by lumped-parameter elements, and a thick dielectric substrate lies beneath the patch antenna of the butterfly antenna.

[0036] 200: Construct the equivalent circuit model of the lumped parameter elements of the simulated antenna.

[0037] In some implementations, an equivalent circuit model can be formed by connecting a reactive element in series with an LRC parallel resonant circuit.

[0038] Figure 4 The diagram shows the equivalent circuit model of the lumped parameter elements of the simulated antenna constructed using the UHF sensor simulation antenna construction method described in this invention, in one embodiment.

[0039] like Figure 4 As shown, in a more specific embodiment, the lumped parameter element may include four elements: a reactance element X, a first capacitor C1, a first inductor L1, and a first resistor R1. The first capacitor C1, the first inductor L1, and the first resistor R1 are connected in parallel to form an LRC parallel resonant circuit. Figure 4 In this context, R represents the load resistance of the antenna.

[0040] 300: Obtain the geometric parameters of the geometric model; and determine the initial parameters of the equivalent circuit model based on the input impedance parameters of the physical UHF sensor antenna.

[0041] In some implementations, the resonant frequency f of the butterfly antenna can be determined based on the frequency of the ultra-high frequency electromagnetic waves radiated by partial discharge. r Its relationship with the size of the butterfly antenna is as follows (1):

[0042]

[0043]

[0044]

[0045]

[0046] Where K, Δl, X e All are resonant frequencies f r The intermediate parameters in the formula are expressed by the three equations in formula (2): c is the speed of light in vacuum, w is the length of the bottom edge of the butterfly antenna (unit: mm), H is the total arm length of the butterfly antenna (unit: mm), h is the thickness of the dielectric layer of the butterfly antenna (unit: mm), which is a set value, ε r This represents the relative permittivity of the dielectric substrate.

[0047] Based on the above formulas (1) and (2), the geometric parameters H and w of the butterfly antenna can be calculated.

[0048] In addition, the initial parameters of the equivalent circuit model need to be determined based on the input impedance parameters of the physical UHF sensor antenna.

[0049] In some implementations, the input impedance parameter of the physical UHF sensor antenna can be obtained from the ratio between the voltage value measured by the physical UHF sensor antenna and the pulse current. This input impedance parameter includes a real part and an imaginary part, where the real part function Re[Z(ω)] and the imaginary part function Im[Z(ω)] are as follows, where ω is the independent variable of the input impedance parameter, i.e., the antenna receiving frequency.

[0050]

[0051] In some implementations, the value of the reactance element X can be set. For example, in a specific instance, it can be set to 50nH based on experience. R represents the load resistance of the antenna, which can be set to 0 in a specific instance. The initial parameters of the equivalent circuit model, the first capacitor C1, the first inductor L1 and the first resistor R1, can be calculated according to the above formula (3).

[0052] 400: A simulated partial discharge pulse current corresponding to the actual partial discharge signal is generated by a simulated partial discharge power supply. The simulated signal obtained by the simulated antenna is compared with the measured signal measured by the physical UHF sensor antenna. Based on the comparison results, the parameters of the equivalent circuit model are adjusted so that the simulated signal matches the measured signal.

[0053] In some implementations, a simulated partial discharge power supply is established in XFDTD7.3.0 software, which emits simulated partial discharge pulses corresponding to the actual partial discharge signal. The simulated signal obtained by the simulated antenna is compared with the measured signal measured by the physical UHF sensor antenna. Based on the comparison results, the inductance value of the first inductor L1 and the capacitance value of the first capacitor C1 of the lumped parameter element are finely adjusted in XFDTD7.3.0 software to make the simulation results match the experimental results. Finally, an equivalent circuit model with determined parameters is obtained, and thus the simulated antenna is obtained.

[0054] To verify the effectiveness of this invention, pulse current and ultra-high frequency signals collected during partial discharge were used for verification:

[0055] Partial discharge data was collected in the high-voltage testing hall. A physical UHF sensor was placed 30cm from the discharge point, and pressure was applied to cause breakdown between 3mm insulating plates. A current sensor collected the pulse current, and the UHF sensor collected the UHF signal. The actual measured current signal is as follows: Figure 5 As shown in Figure 6, the actual measured UHF signal is as shown in Figure 6.

[0056] The simulated antenna, constructed based on an actual UHF sensor antenna, has a total arm length H of 16mm, a base length w of 4mm, and a dielectric layer thickness h of 1mm. Next, the equivalent circuit model of the simulated antenna is obtained using the input impedance parameter curve of the actual UHF sensor antenna. Then, the... Figure 5 The actual current signal shown is used as the excitation to simulate the antenna response. The antenna response is then fine-tuned by comparing it with the actual signal. Finally, the values ​​of the first inductor L1, the first capacitor C1, and the first resistor R1 of the lumped elements are determined to be 120nH, 1100pF, and 50Ω, respectively.

[0057] Figure 7 The comparison shows the actual UHF signal of partial discharge and the simulated signal obtained by the simulated antenna. From Figure 7 As can be seen, under the same excitation waveform, the waveform change trend of the actually measured UHF signal matches that of the simulation result. The received UHF signal oscillates and attenuates. At the same time scale, the oscillation periods of the two are basically the same. In terms of relative height, there is only a significant difference at the first peak after the attenuation of the highest peak. This fully demonstrates that the simulated antenna constructed using the method described in this invention has high simulation accuracy.

[0058] It should be noted that the scope of protection of the prior art in this invention is not limited to the embodiments given in this application. All prior art that does not contradict the solution of this invention, including but not limited to prior patent documents, prior publications, prior public uses, etc., can be included in the scope of protection of this invention.

[0059] Furthermore, the combination of the technical features in this case is not limited to the combination methods described in the claims of this case or the combination methods described in the specific embodiments. All technical features described in this case can be freely combined or combined in any way, unless they contradict each other.

[0060] It should also be noted that the embodiments listed above are merely specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and similar changes or modifications made thereto are those that can be directly derived or easily conceived by those skilled in the art from the content disclosed in the present invention, and should all fall within the protection scope of the present invention.

Claims

1. A method for constructing a UHF sensor simulation antenna, characterized in that, Including the following steps: Establish a geometric model of the simulated antenna corresponding to the physical UHF sensor antenna; Construct an equivalent circuit model of the lumped parameter element of the simulated antenna, wherein the lumped parameter element is connected to the geometric model; Obtain the geometric parameters of the geometric model; The initial parameters of the equivalent circuit model are determined based on the input impedance parameters of the physical UHF sensor antenna. The geometric parameters of the geometric model are obtained by: selecting the resonant frequency of the antenna based on the frequency of the ultra-high frequency electromagnetic wave radiated by partial discharge, and calculating the required geometric parameters based on the resonant frequency. A simulated partial discharge pulse current corresponding to the actual partial discharge signal is generated by a simulated partial discharge power supply. The simulated signal obtained by the simulated antenna is compared with the measured signal measured by the physical UHF sensor antenna. Based on the comparison results, the parameters of the equivalent circuit model are adjusted to make the simulated signal match the measured signal.

2. The method for constructing a UHF sensor simulation antenna as described in claim 1, characterized in that, The physical ultra-high frequency sensor antenna is a dipole antenna.

3. The method for constructing a UHF sensor simulation antenna as described in claim 2, characterized in that, The dipole antenna is a butterfly antenna.

4. The method for constructing a UHF sensor simulation antenna as described in claim 3, characterized in that, The geometric parameters of the geometric model corresponding to the butterfly antenna include: the arm length of the butterfly antenna and the base length of the butterfly antenna.

5. The method for constructing a UHF sensor simulation antenna as described in claim 1, characterized in that, The construction of the equivalent circuit model of the lumped parameter element specifically includes: using a reactive element and an LRC parallel resonant circuit in series to form the equivalent circuit model.

6. The method for constructing a UHF sensor simulation antenna as described in claim 5, characterized in that, The LRC parallel resonant circuit includes a first capacitor, a first inductor, and a first resistor connected in parallel with each other.

7. The method for constructing a UHF sensor simulation antenna as described in claim 1, characterized in that, The input impedance parameter of the physical UHF sensor antenna is obtained by comparing the voltage value measured by the physical UHF sensor antenna with the pulse current.

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