CN216290857U - Filtering and amplifying module for impulse response method winding deformation detection device - Google Patents
Filtering and amplifying module for impulse response method winding deformation detection device Download PDFInfo
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- CN216290857U CN216290857U CN202122921414.6U CN202122921414U CN216290857U CN 216290857 U CN216290857 U CN 216290857U CN 202122921414 U CN202122921414 U CN 202122921414U CN 216290857 U CN216290857 U CN 216290857U
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Abstract
The utility model provides a filtering and amplifying module for a winding deformation detection device by an impulse response method, which comprises: the filtering unit is used for filtering clutter and is connected with the response signal of the transformer; the amplifying unit is used for amplifying the signal and is connected with the output end of the filtering unit; the filtering unit and the amplifying unit are independently arranged on the winding deformation detection device, the circuit structure is simple, the fault points are reduced due to the modularized arrangement, the cut-off frequency and the amplification factor can be flexibly adjusted according to needs, the disassembly and the assembly are facilitated, the maintenance is convenient, the interference of the high-voltage transformer on the filtering circuit, the amplifying circuit and the filtered response signals is shielded, meanwhile, the power is independently supplied to the inside of the module, the electromagnetic interference is prevented, the shielding is reliable, and the accuracy of the transformer winding deformation test result is improved.
Description
Technical Field
The utility model relates to the technical field of transformer winding deformation detection, in particular to a filtering amplification module for a winding deformation detection device adopting an impulse response method.
Background
The deformation of the transformer winding is one of the main causes for inducing the transformer accident, the timely detection and elimination of the winding deformation fault are very important, in order to realize timely early warning and real-time analysis of fault conditions and ensure that the transformer is detected in a non-power-off state, the deformation fault of a transformer winding is mostly detected by using an impulse response method, the impulse response method transmits an impulse signal sent by an impulse source to the transformer winding, the transformer winding generates a response signal, fourier transformation is carried out on the response signal to obtain an analysis and calculation result so as to obtain the deformation condition of the transformer winding, however, the response signal at the transformer winding usually overlaps odd harmonics of the working frequency and other frequencies of the transformer itself, and in the prior art, the filtering and amplifying effect is realized by the high-pass filter and the amplifier which are integrally arranged with the calculation processing unit, so that the response signal only retains an effective high-frequency signal under an ideal state. However, the high-pass filter and the amplifier have complex circuit structures and more fault points, are integrally arranged with the calculation and analysis module, and are usually arranged adjacent to the transformer, and the transformer in the transformer substation usually has a voltage grade of 35kV-220kV, and can generate higher interference signals to influence the detection result, so that the deformation data of the transformer winding obtained after filtering still has a difference from the actual situation.
SUMMERY OF THE UTILITY MODEL
The utility model aims to at least solve the technical problem that the deformation of a transformer winding cannot be accurately measured due to the fact that the transformer winding and a calculation and analysis module are integrally arranged, multiple fault points are provided, and the transformer winding cannot be accurately measured due to the interference of signals of a high-voltage transformer in the prior art.
Therefore, the utility model provides a filtering and amplifying module for a winding deformation detection device by an impulse response method.
The utility model provides a filtering and amplifying module for a winding deformation detection device by an impulse response method, which comprises the following components: the filtering unit is used for filtering clutter and is connected with the response signal of the transformer;
the amplifying unit is used for amplifying the signal and is connected with the output end of the filtering unit;
the filtering unit and the amplifying unit are independently arranged on the winding deformation detection device.
According to the filtering and amplifying module for the winding deformation detection device adopting the impulse response method, the filtering unit can filter the working frequency of 50Hz and high-frequency components thereof, including odd harmonics such as 150Hz and 250Hz, of the transformer, and keeps high-frequency signals of impulse response, and the amplifying unit can amplify the high-frequency signals output by the filtering unit, so that the signal-to-noise ratio is improved; the filtering unit and the amplifying unit are independently arranged, so that compared with the integrated arrangement with the calculation and analysis module, the fault points are fewer, the filtering unit and the amplifying unit can be replaced at any time, the use and the maintenance are convenient, the filtering unit and the amplifying unit become independent module parts, the filtering unit or the amplifying unit with different cut-off frequencies or amplification factors can be selected according to different site grades, and the independent shielding of output signals of the filtering unit becomes possible.
According to the technical scheme of the utility model, the filtering and amplifying module for the winding deformation detection device by the impulse response method can also have the following additional technical characteristics:
in the above technical scheme, the filtering unit and/or the amplifying unit are/is arranged in the shielding box, a power module is arranged in the shielding box, and the power module is connected with the filtering unit and the amplifying unit.
In the technical scheme, the shielding box shields the interference of the high-voltage transformer on the filtering unit and the amplifying unit, secondary interference after filtering is avoided, and the response signal transmitted to the calculation and analysis module is ensured to be accurate enough, so that the accurate judgment of the deformation condition of the transformer winding is realized; meanwhile, the power module is used for independently supplying power to the filtering unit and the amplifying unit, so that the power supply problem is solved, the electromagnetic interference is prevented, and the reliable shielding is realized.
In the above technical solution, the shielding box is provided with a BNC inlet and a BNC outlet, the filtering unit is connected to the transformer response signal through the BNC inlet, and the amplifying unit outputs the amplified signal through the BNC outlet.
In the technical scheme, the connection is convenient through the arrangement of the BNC inlet (coaxial cable interface) and the BNC outlet, the filtering amplification module and the detection device can be assembled and disassembled at any time, and the connection step is simplified.
In the above technical scheme, the shielding box is made of stainless steel, and the power module includes a lithium battery.
In any of the above technical solutions, the filtering unit includes a first resistor, a second resistor, a third resistor, a first capacitor, and a first operational amplifier, one end of the first resistor is connected to ground, the other end of the first resistor is connected to a non-inverting input terminal of the first operational amplifier, one end of the first capacitor is connected to a response signal terminal of the transformer, the other end of the first capacitor is connected to the non-inverting input terminal of the first operational amplifier, one end of the second resistor is connected to ground, the other end of the second resistor is connected to an inverting input terminal of the first operational amplifier, the third resistor is connected in parallel to a position between the inverting input terminal and an output terminal of the first operational amplifier, and the output terminal of the first operational amplifier is connected to an input terminal of the amplifying unit.
In the technical scheme, one end of a first capacitor is connected with a response signal of a transformer through a BNC inlet, and a power supply module supplies electric energy to a first operational amplifier.
In the above technical solution, the cutoff frequency of the filtering unit is:
wherein R is1Is the resistance value of the first resistor, C1Is the capacitance value of the first capacitor.
In the technical scheme, the medium frequency is controlled by adjusting the numerical values of the first resistor and the first capacitor, when the cutoff frequency is 1kHz, the first resistor can be selected to be 15.7k omega, the first capacitor can be selected to be 0.1uF, and meanwhile, the resistance values of the second resistor and the third resistor are 10k omega to limit overcurrent.
In any of the above technical solutions, the amplifying module includes a fourth resistor, a fifth resistor, a sixth resistor, and a second operational amplifier, one end of the fourth resistor is connected to the output end of the filtering unit, the other end of the fourth resistor is connected to the non-inverting input end of the second operational amplifier, one end of the fifth resistor is connected to ground, the other end of the fifth resistor is connected to the inverting input end of the second operational amplifier, and the sixth resistor is connected in parallel between the inverting input end and the output end of the first operational amplifier.
In the technical scheme, one end of the fourth resistor is connected with the output end of the first operational amplifier, and the power supply module supplies electric energy to the second operational amplifier.
In the above technical solution, the amplification factor of the amplification unit is:
wherein R is5Is the resistance value of the fifth resistor, R6Is the resistance of the sixth resistor.
In this embodiment, when the amplification factor is 10 times, the sixth resistor is 9k Ω, the fifth resistor is 1k Ω, and the fourth resistor is 10k Ω for limiting the overcurrent.
In summary, due to the adoption of the technical scheme, the utility model has the beneficial effects that: the filtering and amplifying module for the pulse response method winding deformation detection device is simple in circuit structure, modularized in arrangement, capable of reducing fault points, capable of flexibly adjusting cut-off frequency and amplification factor according to needs, beneficial to disassembly and assembly, convenient to maintain, capable of shielding interference of a high-voltage transformer on the filtering circuit, the amplifying circuit and response signals after filtering, capable of preventing electromagnetic interference due to independent power supply inside the module, reliable in shielding and capable of improving accuracy of transformer winding deformation test results.
Additional aspects and advantages of the utility model will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
fig. 1 is a perspective view of a filter amplification module for an impulse response winding deformation detection apparatus according to an embodiment of the present invention;
fig. 2 is a structural diagram of a filter amplification module for an impulse response winding deformation detection apparatus according to an embodiment of the present invention;
fig. 3 is a circuit diagram of a filtering unit in a filtering amplification module for an impulse response winding deformation detection apparatus according to an embodiment of the present invention;
fig. 4 is a circuit diagram of an amplifying unit in a filter amplifying module for an impulse response winding deformation detecting apparatus according to an embodiment of the present invention;
FIG. 5 is a diagram illustrating the result of testing the frequency band of the high-pass filter circuit of the filter amplifying module of the winding deformation detecting apparatus according to the impulse response method;
fig. 6 is a diagram illustrating a test result of an equal-scale amplifying circuit of a filter amplifying module of a winding deformation detecting apparatus according to an embodiment of the present invention.
Wherein, the correspondence between the reference numbers and the part names in fig. 1 to 6 is:
1. a shield case; 2. a power supply module; 3. a BNC outlet; 4. a BNC inlet; 5. a filtering unit; 6. a fixing leg; 7. an amplifying unit; r1, a first resistor; r2, a second resistor; r3, third resistor; r4, fourth resistor; r5, fifth resistor; r6, sixth resistor; c1, a first capacitance; a1, a first operational amplifier; a2, a second operational amplifier.
Detailed Description
In order that the above objects, features and advantages of the present invention can be more clearly understood, a more particular description of the utility model will be rendered by reference to the appended drawings. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced otherwise than as specifically described herein, and thus the scope of the present invention is not limited by the specific embodiments disclosed below.
A filtering and amplifying module for an impulse response winding deformation detecting apparatus according to some embodiments of the present invention is described below with reference to fig. 1 to 6.
Some embodiments of the present application provide a filtering and amplifying module for an impulse response winding deformation detecting apparatus.
As shown in fig. 1 to 4, a first embodiment of the present invention provides a filtering and amplifying module for an impulse response winding deformation detecting apparatus, including: the filtering unit 5 is used for filtering clutter and is connected with the response signal of the transformer;
the amplifying unit 7 is used for amplifying signals and is connected with the output end of the filtering unit 5;
the filtering unit 5 and the amplifying unit 7 are independently arranged on the winding deformation detection device.
In this embodiment, the filtering unit 5 may filter the working frequency of the transformer itself, which is 50Hz, and its high frequency components, which include odd harmonics such as 150Hz and 250Hz, and retain the high frequency signal of the impulse response, and the amplifying unit 7 may amplify the high frequency signal output by the filtering unit 5, so as to improve the signal-to-noise ratio; the filtering unit 5 and the amplifying unit 7 are arranged independently, compared with the situation that the fault points are fewer when the filtering unit 5 and the amplifying unit 7 are arranged integrally with a calculation and analysis module, the filtering unit 5 and the amplifying unit 7 can be replaced at any time and are convenient to use and maintain, the filtering unit 5 and the amplifying unit 7 become independent module parts, the filtering unit 5 or the amplifying unit 7 with different cut-off frequencies or amplification factors can be selected according to different site grades, and meanwhile, the independent shielding of output signals of the filtering unit 5 becomes possible.
The second embodiment of the present invention provides a filtering and amplifying module for a winding deformation detection device using an impulse response method, and based on the first embodiment, as shown in fig. 1 to 4, the filtering unit 5 and/or the amplifying unit 7 are/is disposed in a shielding box 1, a power module 2 is disposed in the shielding box 1, and the power module 2 is connected to the filtering unit 5 and the amplifying unit 7.
In the embodiment, the shielding box 1 shields the interference of the high-voltage transformer on the filtering unit 5 and the amplifying unit 7, secondary interference after filtering is avoided, and it is ensured that a response signal transmitted to the calculation and analysis module is accurate enough, so that accurate judgment of the deformation condition of the transformer winding is realized, the shielding box 1 comprises a box body and a box cover, the box body and the box cover are detachably connected, the internal circuit is convenient to overhaul, the box body is provided with fixing pins 6, and the fixing of the shielding box 1 is realized through the fixing pins 6; meanwhile, the power module 2 independently supplies power to the filtering unit 5 and the amplifying unit 7, so that the power supply problem is solved, the electromagnetic interference is prevented, and the reliable shielding is realized.
The third embodiment of the present invention provides a filtering and amplifying module for an impulse response winding deformation detecting device, and based on any of the above embodiments, as shown in fig. 1 to 4, the shielding box 1 is provided with a BNC inlet 4 and a BNC outlet 3, the filtering unit 5 is connected to the transformer response signal through the BNC inlet 4, and the amplifying unit 7 outputs the amplified signal through the BNC outlet 3.
In this embodiment, the BNC inlet 4 (coaxial cable interface) and the BNC outlet 3 are arranged, so that the connection is facilitated, the filtering and amplifying module and the detection device can be assembled and disassembled at any time, and the connection step is simplified.
A fourth embodiment of the present invention provides a filtering and amplifying module for a winding deformation detection device using an impulse response method, and based on any of the above embodiments, as shown in fig. 1 to 4, the filtering and amplifying module includes a shielding box 1 made of a stainless steel material, and a power module 2 including a lithium battery.
A fifth embodiment of the present invention provides a filtering and amplifying module for an impulse response winding deformation detecting device, and as shown in fig. 1 to 4, the filtering unit 5 includes a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1 and a first operational amplifier a1, one end of the first resistor R1 is connected to ground, the other end of the first resistor R1 is connected to the non-inverting input terminal of the first operational amplifier a1, one end of the first capacitor C1 is connected to a transformer response signal terminal, the other end of the first capacitor C1 is connected to the non-inverting input terminal of the first operational amplifier a1, one end of the second resistor R2 is connected to ground, the other end of the second resistor R2 is connected to the inverting input terminal of the first operational amplifier a1, the third resistor R3 is connected in parallel between the inverting input terminal and the output terminal of the first operational amplifier a1, the output of the first operational amplifier a1 is connected to the input of the amplification unit 7.
In this embodiment, one terminal of the first capacitor C1 is connected to the transformer response signal through the BNC inlet 4, and the power module 2 provides power to the first operational amplifier a 1.
A sixth embodiment of the present invention provides a filtering and amplifying module for an impulse response winding deformation detecting device, and based on any of the above embodiments, as shown in fig. 1 to 4, the cutoff frequency of the filtering unit 5 is:
wherein R is1Is the resistance value, C, of the first resistor R11Is the capacitance value of the first capacitor C1.
In this embodiment, the medium frequency is controlled by adjusting the values of the first resistor R1 and the first capacitor C1, when the cutoff frequency is 1kHz, the first resistor R1 may use 15.7k Ω, the first capacitor C1 may use 0.1uF, and the second resistor R2 and the third resistor R3 have 10k Ω to limit the overcurrent.
As shown in FIG. 5, the band test of the high-pass filter circuit is performed, a sinusoidal signal with a frequency of 1Hz-10MHz is input to the input end, and the input and output filter parameters are analyzed, so that the 3dB cutoff frequency of the filter circuit is about 1kHz, and the requirements are met.
A seventh embodiment of the present invention provides a filtering and amplifying module for an impulse response winding deformation detecting apparatus, and based on any of the above embodiments, as shown in fig. 1 to 4, the amplifying module includes a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, and a second operational amplifier a2, one end of the fourth resistor R4 is connected to the output terminal of the filtering unit 5, the other end of the fourth resistor R4 is connected to the non-inverting input terminal of the second operational amplifier a2, one end of the fifth resistor R5 is connected to ground, the other end of the fifth resistor R5 is connected to the inverting input terminal of the second operational amplifier a2, and the sixth resistor R6 is connected in parallel between the inverting input terminal and the output terminal of the first operational amplifier a 1.
In this embodiment, one end of the fourth resistor R4 is connected to the output terminal of the first operational amplifier a1, and the power module 2 supplies power to the second operational amplifier a 2.
An eighth embodiment of the present invention provides a filtering and amplifying module for an impulse response winding deformation detecting device, and on the basis of any of the above embodiments, as shown in fig. 1 to 5, the amplification factor of the amplifying unit 7 is:
wherein R is5Is the resistance of the fifth resistor R5, R6Is the resistance of the sixth resistor R6.
In this embodiment, when the amplification factor is 10 times, the sixth resistor R6 is 9k Ω, the fifth resistor R5 is 1k Ω, and the fourth resistor R4 is 10k Ω for limiting the overcurrent.
As shown in fig. 6, the equal-scale amplifying circuit test is performed, a sinusoidal signal with a frequency of 1kHz to 10MHz is input at the input end, and the input and output filtering parameters are analyzed, so that it can be seen that the amplifying times of the amplifying circuit in the frequency band are all 10 times, which meets the requirements.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. A filtering and amplifying module for an impulse response method winding deformation detection device is characterized by comprising the following components:
the filtering unit (5) is used for filtering out clutter and is connected with the response signal of the transformer;
the amplifying unit (7) is used for amplifying the signals and is connected with the output end of the filtering unit (5);
the filtering unit (5) and the amplifying unit (7) are independently arranged on the winding deformation detection device.
2. The filter amplification module for the winding deformation detection device adopting the impulse response method according to claim 1, wherein the filter unit (5) and/or the amplification unit (7) are/is arranged in a shielding box (1), a power supply module (2) is arranged in the shielding box (1), and the power supply module (2) is connected with the filter unit (5) and the amplification unit (7).
3. The filter amplification module for winding deformation detection device by impulse response method according to claim 2, wherein the shielding box (1) is provided with a BNC inlet (4) and a BNC outlet (3), the filter unit (5) is connected with the transformer response signal through the BNC inlet (4), and the amplification unit (7) outputs the amplified signal through the BNC outlet (3).
4. The filter amplification module for winding deformation detection device of impulse response method according to claim 3, characterized in that the shielding box (1) is made of stainless steel material, and the power module (2) comprises lithium battery.
5. A filter amplification module for an impulse response winding deformation detection device according to any one of claims 1 to 4, wherein the filter unit (5) comprises a first resistor (R1), a second resistor (R2), a third resistor (R3), a first capacitor (C1), and a first operational amplifier (A1), one end of the first resistor (R1) is connected to ground, the other end of the first resistor (R1) is connected to the non-inverting input terminal of the first operational amplifier (A1), one end of the first capacitor (C1) is connected to the transformer response signal terminal, the other end of the first capacitor (C1) is connected to the non-inverting input terminal of the first operational amplifier (A1), one end of the second resistor (R2) is connected to ground, the other end of the second resistor (R2) is connected to the inverting input terminal of the first operational amplifier (A1), and the third resistor (R3) is connected in parallel to the inverting input terminal of the first operational amplifier (A1), the output of the first operational amplifier (a1) is connected to the input of the amplification unit (7).
6. The filter amplification module for an impulse response winding deformation detection device according to claim 5, characterized in that the cutoff frequency of the filter unit (5) is:
wherein is R1Resistance value, C, of the first resistor (R1)1Is the capacitance value of the first capacitor (C1).
7. A filter amplification module for an impulse response winding deformation detection device according to any one of claims 1 to 4, characterized in that the amplification module comprises a fourth resistor (R4), a fifth resistor (R5), a sixth resistor (R6) and a second operational amplifier (A2), one end of the fourth resistor (R4) is connected with the output terminal of the filter unit (5), the other end of the fourth resistor (R4) is connected with the non-inverting input terminal of the second operational amplifier (A2), one end of the fifth resistor (R5) is connected with ground, the other end of the fifth resistor (R5) is connected with the inverting input terminal of the second operational amplifier (A2), and the sixth resistor (R6) is connected in parallel between the inverting input terminal and the output terminal of the first operational amplifier (A1).
8. The filter amplification module for an impulse response winding deformation detection device according to claim 7, characterized in that the amplification factor of the amplification unit (7) is:
wherein R is5Is the resistance value of the fifth resistor (R5), R6Is the resistance value of the sixth resistor (R6).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122921414.6U CN216290857U (en) | 2021-11-25 | 2021-11-25 | Filtering and amplifying module for impulse response method winding deformation detection device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122921414.6U CN216290857U (en) | 2021-11-25 | 2021-11-25 | Filtering and amplifying module for impulse response method winding deformation detection device |
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| CN216290857U true CN216290857U (en) | 2022-04-12 |
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| CN202122921414.6U Active CN216290857U (en) | 2021-11-25 | 2021-11-25 | Filtering and amplifying module for impulse response method winding deformation detection device |
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2021
- 2021-11-25 CN CN202122921414.6U patent/CN216290857U/en active Active
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