GIS insulator and surface charge polarity online distinguishing method and device thereof

Abstract

The application discloses a GIS surface charge monitoring method and a GIS insulator structure with the method. The GIS surface charge monitoring method sets a sensor on the GIS to acquire electric field information and position information of a GIS surface, and then determines the working state of the GIS according to the electric field information and the position information, thereby reducing the probability of failure of the GIS.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power transmission and transformation equipment state sensing, in particular to a GIS insulator and a surface charge polarity online discrimination method and element thereof. BACKGROUND

[0002] Gas Insulated Switchgear (GIS) is a kind of combined metal-enclosed switchgear, which has the characteristics of compact structure, small floor area, high reliability, strong safety, strong environmental adaptability, small maintenance workload, etc., and is widely used in power systems. With the increase of the scale of China's power grid, the installation and use of GIS equipment has increased significantly, and the accompanying faults also occur frequently. Surface flashover caused by insulator failure is considered to be an important reason for the occurrence of faults.

[0003] Surface defects of the insulator can cause local electric field concentration and induce partial discharge, and the surface charge accumulation and surface electric field distortion caused by the partial discharge are important factors affecting the insulation performance of the GIS insulator. When exploring the influence of surface charge accumulation and its electric field distortion on the flashover characteristics of the insulator, online discrimination of the polarity of the surface charge of the insulator will be beneficial to the analysis of the distortion effect of the surface charge on the electric field.

[0004] In the traditional surface charge measurement, the measurement of the surface charge of the insulator and its distorted electric field is mainly in an offline manner, and the measurement is carried out by using an electrometer and the like under the condition of no charge. This offline method cannot obtain the real-time change of the surface charge accumulation of the insulator under the condition of charged operation, which is not conducive to the study of the role of the surface charge of the insulator in the flashover process and the mechanism of causing flashover. Therefore, there is an urgent need for an online measurement method to realize real-time online discrimination of the polarity of the surface charge. SUMMARY

[0005] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a GIS insulator surface charge polarity online discrimination method, which can solve the problem of difficult and timely discovery of fault hidden dangers in the installation and operation of GIS.

[0006] The present application also proposes an element relied on by the above-mentioned GIS insulator surface charge polarity online discrimination method.

[0007] The GIS insulator surface charge polarity discrimination method according to the first aspect embodiment of the present application is characterized in that it comprises the following steps:

[0008] The state of the GIS insulator operation is obtained by using a rotating electric field sensor and a position sensor, and electric field sensor data and position sensor data are obtained respectively;

[0009] Based on the electric field sensor data and the position sensor data, the polarity of the GIS insulator surface charge is calculated.

[0010] According to the GIS insulator surface charge polarity determination method, the sensor is arranged on the GIS flange, and then the sensor data is analyzed to calculate the polarity of the insulator surface, so that the misjudgment probability of the GIS fault can be reduced.

[0011] According to some embodiments of the present application, the step of calculating the polarity of the GIS insulator surface charge based on the electric field sensor data and the position sensor data comprises:

[0012] The electric field sensor data is subjected to fast Fourier transform to obtain the amplitude |F(ω1)| and the phase θ(ω1) of the harmonic component with a frequency of ω1;

[0013] Based on the amplitude |F(ω1)| and the phase θ(ω1) of the harmonic component, the signal direct current electric field corresponding signal u′=|F(ω1)|×cos[ω1t+θ(ω1)] is reconstructed.

[0014] When the slope k of the electric field signal u′ is less than 0, the surface charge is positive polarity, and when the slope k is greater than 0, the surface charge is negative polarity.

[0015] According to some embodiments of the present application, the step of calculating the polarity of the GIS insulator surface charge based on the electric field sensor data and the position sensor data comprises:

[0016] The time information of each pulse signal in the position sensor data is extracted;

[0017] The slope k of the electric field signal corresponding to each pulse signal is calculated;

[0018] When the slope k is greater than 0, the surface charge polarity is negative polarity, and when k is less than 0, the surface charge polarity is positive polarity.

[0019] According to some embodiments of the present application, the rotating electric field sensor comprises a rotating electrode, a stationary induction electrode, a direct current motor, a mounting seat and a signal output terminal; the direct current motor can adjust the rotating speed by adjusting the supply voltage.

[0020] The GIS insulator surface charge polarity determination device according to the second aspect of the present application comprises:

[0021] The running monitoring module is used to obtain the state of the GIS insulator running to obtain the electric field sensor data and the position sensor data;

[0022] A polarity judging module is capable of calculating the polarity of the surface charge of the GIS insulator based on the electric field sensor data and the position sensor data.

[0023] Further, the operation monitoring module further comprises:

[0024] An amplitude and phase extracting element is capable of performing fast Fourier transform on the electric field sensor data to obtain the amplitude |F(ω1)| and the phase θ(ω1) of the harmonic component with the frequency ω1. ω1

[0025] A signal reconstructing element is capable of reconstructing the signal u′ corresponding to the direct current electric field based on the amplitude |F(ω1)| and the phase θ(ω1) of the harmonic component, i.e., u′=|F(ω1)|×cos[ω1t+θ(ω1)].

[0026] A first surface polarity judging element is capable of judging that the surface charge is positive polarity when the slope k of the electric field signal u′ is less than 0, and judging that the surface charge is negative polarity when the slope k is greater than 0.

[0027] Further, the operation monitoring module further comprises:

[0028] A time information extracting element is capable of extracting the time information of each pulse signal in the position sensor data.

[0029] A slope calculating element is capable of calculating the slope k of the electric field signal corresponding to each pulse signal.

[0030] A second surface polarity judging element is capable of judging that the surface charge is negative polarity when the slope k is greater than 0, and judging that the surface charge is positive polarity when the slope k is less than 0.

[0031] Additional aspects and advantages of the application will be made apparent by the following description and the appended claims. BRIEF DESCRIPTION OF DRAWINGS

[0032] The above and / or additional aspects and advantages of the application will become apparent and be made clear to the reader after a review of the following description of the embodiments taken in conjunction with the accompanying drawings.

[0033] Figure 1 A step schematic diagram of a GIS insulator surface charge polarity discrimination method is provided for the embodiment of the embodiment of the application;

[0034] Figure 2 A GIS insulator structure schematic diagram is provided for the embodiment of the application;

[0035] Figure 3 A sensor structure schematic diagram is provided for the embodiment of the application;

[0036] ​Figure 4 For Figure 1 The step breakdown diagram of the step S100 in the illustrated step schematic diagram;

[0037] Figure 5 The sensor rotating electrode position schematic diagram provided for the embodiment of the application;

[0038] Figure 6 The electric field induction signal measurement principle schematic diagram provided for the embodiment of the application;

[0039] Figure 7 The relationship between the electric field signal and the position signal under different polarity surface charges for the embodiment of the application;

[0040] Figure 8 The block diagram structure schematic diagram of the GIS insulator surface charge polarity discrimination device provided for the embodiment of the application. DETAILED DESCRIPTION

[0041] The embodiments of the application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the application, and cannot be understood as a limitation of the application.

[0042] In the description of the application, the meaning of several is one or more, the meaning of multiple is two or more, greater than, less than, more than, etc. are understood as not including the number, above, below, etc. are understood as including the number. If it is described that the first, the second is only used to distinguish the technical features for the purpose, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of indicated technical features or implicitly indicating the sequence of indicated technical features.

[0043] In the description of the application, unless otherwise explicitly limited, the words such as setting, installing, connecting, etc. should be understood broadly, and the person skilled in the art can reasonably determine the specific meaning of the above words in the application in combination with the specific content of the technical solution.

[0044] In order to solve the problem of lack of effective built-in UHF sensor sensitivity on-site inspection method in new installation GIS handover test, guarantee the effectiveness of the built-in UHF sensor of new installation GIS, avoid the fault hidden danger caused by insufficient sensor sensitivity.

[0045] In addition, after the GIS runs for a period of time, the built-in UHF sensor sensitivity on-site inspection method can timely grasp the running effectiveness of the GIS, and avoid the fault hidden danger caused by the failure of the GIS.

[0046] ReferenceFigure 1 The embodiment of the application provides a GIS insulator surface charge polarity discrimination method, and at least comprises the following steps:

[0047] In step S100, the state of GIS insulator operation is acquired to obtain electric field sensor data and position sensor data.

[0048] In step S200, the polarity of GIS insulator surface charge is calculated based on the electric field sensor data and the position sensor data.

[0049] In order to more clearly explain the purpose described in the application, the principle and specific implementation details of the above steps are explained in more detail.

[0050] Embodiment one,

[0051] Since the sensor needs to be arranged on the GIS insulator, the structure of the existing GIS sensor needs to be improved, and the structure is as follows.

[0052] Referring to Figure 2 The figure shows the structure of the improved GIS insulator,

[0053] At the flange of the GIS insulator metal cylinder wall, the inner wall is uniformly provided with four rectangular hand holes, and an electric field sensor is arranged in each hand hole.

[0054] Preferably, the shape of the hand hole needs to match the shape of the sensor to have good air tightness, so that the data obtained by the sensor is more accurate.

[0055] The power supply and signal line of the electric field sensor in the hand hole are led out to the outside of the hand hole through the signal terminal on the through device, and the signal collected by the sensor can be output to the outside.

[0056] Further, referring to Figure 3 The figure provides a sensor structure, which comprises a rotating motor, a stationary sensing electrode, a direct current motor for driving the rotating electrode, and corresponding mounting seat and signal output terminal.

[0057] The rotation speed of the direct current motor can be adjusted by adjusting the power supply voltage, and the position sensor is installed near the electric field sensor for measuring the position of the rotating electrode of the electric field sensor.

[0058] Embodiment two,

[0059] In order to measure the performance of the GIS insulator itself, the existing insulator needs to be improved on the basis of the existing insulator to adapt to the demand of timely monitoring. The embodiment provides a GIS insulator surface charge polarity discrimination method. The specific steps include:

[0060] Step S100, obtaining the state of GIS insulator operation, obtaining electric field sensor data and position sensor data.

[0061] Referring to Figure 4 , step S100 specifically comprises:

[0062] Step S101, installing a rotating electric field sensor and a position sensor at the hand hole of the GIS.

[0063] At the flange close to the metal cylinder wall of the GIS insulator, 4 rectangular hand holes are evenly arranged along the circumference of the inner wall for placing the electric field measurement sensor and the position sensor; the power supply and signal line of the electric field sensor and the position sensor in the hand hole are led out to the outside of the hand hole through the signal terminal on the through connector, and the hand hole has good air tightness. And the rotating electric field sensor is installed in the hand hole at the flange.

[0064] Step S102, setting the rotating speed of the rotating electric field sensor as ω r .

[0065] The rotating speed of the rotating electric field sensor is set as ω r rad / s, which is used to measure the electric field change near the surface of the insulator.

[0066] Step S103, obtaining the electric field sensor output signal and the position sensor output signal by using the acquisition device.

[0067] The customized rotating electric field sensor includes a rotating electrode, a stationary sensing electrode, a DC motor for driving the rotating electrode, and corresponding mounting seat and signal output terminal; the rotating speed of the DC motor can be adjusted by adjusting the power supply voltage. The position sensor is installed near the electric field sensor for measuring the position of the rotating electrode of the electric field sensor.

[0068] The output signal u of the rotating electric field sensor and the output signal p of the position sensor are measured synchronously by using an oscilloscope or other signal acquisition device, the oscilloscope is connected with the electric field sensor through a coaxial cable, and the input end of the oscilloscope adopts a high resistance coupling mode.

[0069] Through the above electric field signal u and position signal p, the polarity of the surface charge can be obtained.

[0070] Step S104, determining the polarity of the surface charge based on the electric field signal and the position signal.

[0071] When there is surface charge accumulation on the surface of the insulator, it will generate a direct current electric field E in space. For example Figure 3The working principle of the electric field sensor is shown. In the figure, E is the measured electric field, which can be regarded as a uniform field in a local area because the area of the hand hole is small; ω is the rotating angular velocity of the rotating electrode; and S is the projection area (i.e. the effective sensing area) of the exposed part of the sensing electrode in the direction perpendicular to the electric field. When the opening of the rotating electrode allows the sensing electrode to be exposed, electric charges will be induced on the sensing electrode under the action of the measured electric field. These induced electric charges will flow through the detection impedance to generate an induced signal u. There are two identical induction processes when the rotating electrode rotates one round. The alternating period T1 of the induced signal is half of the rotating period Tr of the rotating electrode, and the alternating angular frequency of the induced signal is twice the rotating angular frequency.

[0072] Suppose that the accumulated electric charges on the surface of the insulator are positive polarity electric charges, the electric field E generated thereby has a direction as shown in Figure 5 When the sensing electrode is exposed during the rotation of the rotating electrode, negative electric charges are induced on the sensing electrode. From Figure 5 (a) to Figure 5 (b), the effective sensing area S increases, and the negative electric charges induced on the sensing electrode increase. As shown in Figure 6 (a), these negative electric charges flow from the grounding point into the sensing electrode, and a positive output signal u is generated on the measurement impedance. At this time, the output signal corresponds to Figure 7 (a) from t1 to t2. From Figure 5 (b) to Figure 5 (c), the effective sensing area S decreases, and the negative electric charges induced on the sensing electrode decrease. As shown in Figure 6 (b), the negative electric charges flow from the sensing electrode into the grounding point, and the signal u on the detection impedance is negative. At this time, the output signal corresponds to Figure 7 (a) from t2 to t3. When the rotating electrode rotates to the position shown in Figure 5 (b), i.e. the position shown in Figure 7 (a) at t2, the position sensor generates a position pulse p. Therefore, when the surface electric charges are positive polarity, the output signal u will change from positive to negative at the time when the position sensor generates the position pulse p, i.e. the slope k of the signal u is negative, as shown in Figure 7 (a). Similarly, as shown in Figure 7 (b), when the surface electric charges of the insulator are negative polarity, the slope k of the output signal u at the time when the position sensor generates the position pulse p is positive. In summary, the direction of the DC electric field, i.e. the polarity of the surface electric charges, can be determined by combining the position measurement of the rotating electrode.

[0073] Therefore, the polarity of the surface electric charges can be determined by the electric field signal u (or) and the position signal p: when the slope k is positive, the polarity of the surface electric charges is negative; and when k is negative, the polarity of the surface electric charges is positive.

[0074] Further, sometimes, the insulator will bear an external AC voltage, so the DC component in the electric field signal u needs to be extracted before the discrimination.

[0075] When there is charge accumulation on the surface of the insulator, and the insulator also bears an external AC voltage, the space electric field is composed of the DC electric field generated by the surface charge and the AC electric field generated by the external voltage, and the result measured by the electric field sensor will also be the superposition of the DC electric field and the AC electric field. At this time, in order to discriminate the polarity of the surface charge, the DC component in the electric field signal u needs to be extracted. The fast Fourier transform is performed on the electric field signal u to obtain the amplitude |F(ω1)| and the phase θ(ω1) of the harmonic component with a frequency of ω1. Based on the amplitude F(ω1)| and the phase θ(ω1), the signal corresponding to the signal DC electric field u' = |F(ω1) x cos[ω1t + θ(ω1)] is reconstructed. Further, the polarity of the surface charge is discriminated by calculating the slope k of the electric field signal u' at the time corresponding to each pulse in the position signal p.

[0076] Therefore, the polarity of the surface charge can be discriminated by the electric field signal u (or u') and the position signal p: when the slope k > 0, the polarity of the surface charge is negative; when k < 0, the polarity of the surface charge is positive.

[0077] Another embodiment of the application provides a device for detecting the lag of an application program, as shown in Figure 8 The device 80 includes a running monitoring module 801 and a polarity judgment module 802.

[0078] The running monitoring module 801 is configured to obtain the state of the GIS insulator, and obtain electric field sensor data and position sensor data.

[0079] The polarity judgment module 802 is configured to calculate the polarity of the surface charge of the GIS insulator based on the electric field sensor data and the position sensor data.

[0080] The embodiments of the application can provide a technical basis for discriminating the surface charge by placing the electric field sensor and the position sensor in the GIS, obtaining the electric field data and the position data of the GIS, and then judging the polarity of the GIS insulator according to the electric field data and the position data, so as to facilitate the discrimination of the fault.

[0081] Further, the running monitoring module 801 further includes:

[0082] The amplitude and phase extraction element is configured to perform fast Fourier transform on the electric field sensor data to obtain the amplitude |F(ω1)| and the phase θ(ω1) of the harmonic component with a frequency of ω1.

[0083] The signal reconstructing element is capable of reconstructing a signal u' corresponding to a direct current electric field based on the amplitude |F(ω1)| and the phase θ(ω1) of the harmonic component, and the signal u' is expressed as u'=|F(ω1)|×cos[ω1t+θ(ω1)].

[0084] The first surface polarity judging element is capable of judging that the surface charge is positive when the slope k of the electric field signal u' is less than 0, and judging that the surface charge is negative when the slope k is greater than 0.

[0085] Further, the operation monitoring module 801 further comprises:

[0086] The time information extracting element is capable of extracting time information of each pulse signal in the position sensor data.

[0087] The slope calculating element is capable of calculating the slope k of the electric field signal corresponding to each pulse signal.

[0088] The second surface polarity judging element is capable of judging that the surface charge is negative when the slope k is greater than 0, and judging that the surface charge is positive when the slope k is less than 0.

[0089] The GIS insulator surface charge polarity judging device of the application program of the embodiment is similar to the principle of the GIS insulator surface charge polarity judging method described in the first embodiment, and thus will not be described here.

[0090] The embodiments of the application are described in detail above with reference to the drawings, but the application is not limited to the above-described embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the application.

[0091] Those skilled in the art should understand that the embodiments of the application can be provided as a method, a system, or a computer program product. Therefore, the application can adopt a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the application can adopt a computer program product in the form of one or more computer usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program codes. The solutions in the embodiments of the application can be implemented in various computer languages, for example, object-oriented programming languages such as Java and interpreted scripting languages such as JavaScript.

[0092] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flowcharts and / or blocks Figure 1 one or more flowcharts and / or blocks

[0093] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart block or blocks. Figure 1 one or more flowcharts and / or blocks Figure 1 one or more flowcharts and / or blocks

[0094] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flowcharts and / or blocks Figure 1 one or more flowcharts and / or blocks

[0095] While the preferred embodiments of the application have been described, additional variations and modifications can be employed by those skilled in the art. Therefore, the appended claims intend to cover all such modifications and variations as fall within the true spirit and scope of the application.

[0096] Obviously, numerous modifications and variations of the present application are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A GIS insulator surface charge polarity discrimination method, characterized in that, The method comprises the following steps: obtaining the running state of the GIS insulator to obtain rotating electric field sensor data and position sensor data; calculating the polarity of the surface charge of the GIS insulator based on the rotating electric field sensor data and the position sensor data, comprising: the rotating electric field sensor data comprises an electric field signal u, and the position sensor data comprises a position signal p; wherein, when the rotating electrode of the rotating electric field sensor rotates to the position with the maximum effective sensing area, the position sensor generates a position pulse p; determining the slope k of the electric field signal u at the time corresponding to the position pulse p; when the slope k > 0, it is determined that the surface charge of the GIS insulator is negative; when the slope k < 0, it is determined that the surface charge of the GIS insulator is positive.

2. The method of claim 1, wherein, The step of calculating the polarity of the surface charge of the GIS insulator based on the rotating electric field sensor data and the position sensor data comprises: The rotational electric field sensor data is subjected to a fast Fourier transform to obtain an amplitude and a phase of a harmonic component with a frequency of ; based on the amplitudes of the harmonic components and the phases to reconstruct a signal corresponding to the signal direct current field When the slope k of the electric field signal is k < 0, the surface charge is positive, and when k > 0, the surface charge is negative.

3. The method of claim 1, wherein, the rotating electric field sensor comprises a rotating electrode, a stationary sensing electrode, a direct current motor, a mounting seat and a signal output terminal; the direct current motor can adjust the rotating speed by adjusting the supply voltage.

4. A device for determining the polarity of surface charge on a GIS insulator, which applies the method for determining the polarity of surface charge on a GIS insulator described in claim 1, characterized in that, comprising: a running monitoring module for obtaining the running state of the GIS insulator to obtain rotating electric field sensor data and position sensor data; a polarity judgment module capable of calculating the polarity of the surface charge of the GIS insulator based on the rotating electric field sensor data and the position sensor data.

5. The apparatus of claim 4, wherein, The running monitoring module further comprises: An amplitude and phase extraction element is capable of performing a fast Fourier transform on the rotating electric field sensor data to obtain the amplitude and phase of the harmonic component with frequency ​ a signal reconstruction element, capable of reconstructing a signal corresponding to the signal direct current field based on the amplitudes and phases of the harmonic components ; The first surface polarity judging element judges the surface charge as positive polarity when the slope k of the electric field signal is k<0, and judges the surface charge as negative polarity when the slope k is k>0.

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