CN210351109U

CN210351109U - Partial discharge input signal isolation filter device

Info

Publication number: CN210351109U
Application number: CN201921395776.2U
Authority: CN
Inventors: 欧定军; 黄培刚; 蔡绍军
Original assignee: Shanghai Juter High Voltage Electrical & Equipment Co ltd
Current assignee: Shanghai Juter High Voltage Electrical & Equipment Co ltd
Priority date: 2019-08-24
Filing date: 2019-08-24
Publication date: 2020-04-17
Anticipated expiration: 2029-08-24

Abstract

The utility model relates to an appearance detection technology field is put in office, discloses an input signal isolation filter equipment is put in office, including the BNC input, the one end ground connection of BNC input, its other end electricity is connected with filter capacitor C1, filter capacitor C1 keep away from the one end electricity of BNC input is connected with mutual-inductor T1, and mutual-inductor T1 embeds 2 input terminals and 2 output terminals, and filter capacitor C1 is connected with 1 input terminal electricity among them, another input terminal ground connection; the transformer T1 is electrically connected with a BNC output end, and the BNC output end is provided with two terminals which are respectively and correspondingly and electrically connected with the two output terminals of the transformer T1; the filter capacitor C1 filters signals, and the mutual inductor T1 electrically isolates the signals, so that the local discharge background caused by multipoint grounding is inhibited from being enlarged, and the background noise of the local discharge system is effectively reduced.

Description

Partial discharge input signal isolation filter device

Technical Field

The utility model relates to an appearance detection technology field is put in the office, and more specifically says that it relates to an input signal isolation filter is put in office.

Background

The partial discharge instrument can sense the high-frequency signals generated by the fault, vibration, leakage and electric partial discharge of the operating equipment. The method converts signals into audio signals by using a heterodyne method, enables users to hear the sounds through earphones, can vividly display discharge images by using an advanced visual ultrasonic principle and a delicate sensing technology, and informs maintenance personnel to overhaul in three modes of numbers, sounds and images, so that the safe operation of the GIS is ensured.

In the prior art, when partial discharge is generated under test voltage, pulse current is generated through a coupling capacitor, a pulse signal is picked up by an input unit, and after low-noise pre-amplification, filter amplifier selection of a required frequency band and main amplification, discharge pulse is displayed on an elliptic scanning baseline of an oscillographic screen and is also sent to a pulse peak value table to display the peak value of the discharge pulse.

However, in the prior art, an input signal part in the partial discharge instrument has no isolation filtering function, so that the accuracy of an output signal can be reduced when the input signal is too miscellaneous, and components of the input signal part can be damaged when the energy of the input signal is too high.

SUMMERY OF THE UTILITY MODEL

Put the partial technical problem who does not have the part of isolation filtering function of input signal in the appearance to current office, the utility model provides an input signal keeps apart filter equipment is put in office, and it lets the office put the partial function that has the isolation filtering of input signal in the appearance.

In order to achieve the above purpose, the utility model provides a following technical scheme:

an input signal isolation and filtering device for partial discharge comprises a BNC input end, wherein one end of the BNC input end is grounded, the other end of the BNC input end is electrically connected with a filtering capacitor C1, one end, far away from the BNC input end, of a filtering capacitor C1 is electrically connected with a mutual inductor T1, 2 input terminals and 2 output terminals are arranged in the mutual inductor T1, the filtering capacitor C1 is electrically connected with 1 input terminal, and the other input terminal is grounded;

the transformer T1 is electrically connected with a BNC output end, and the BNC output end is provided with two terminals and is respectively electrically connected with the two output terminals of the transformer T1 in a one-to-one correspondence manner.

Through the technical scheme, the filter capacitor C1 filters the signal, the mutual inductor T1 electrically isolates the signal, the local discharge background amplification caused by multipoint grounding is restrained, and the background noise of the local discharge system is effectively reduced.

Further, the transformer T1 is set as a common mode inductor L1.

Through the technical scheme, the common-mode inductor L1 is used as the mutual inductor T1, so that isolation can be realized, common-mode rejection can be realized, and the purity and the safety of signals are improved.

Further, the BNC input end and the BNC output end are configured as a coaxial cable signal line, the coaxial cable signal line includes an inner connector and an outer connector, the inner connector of the BNC input end is electrically connected to the filter capacitor C1, and the outer connector of the BNC input end is grounded; the inner connector of the BNC output end is electrically connected with the output terminal close to the filter capacitor C1 to form an output H, and the outer connector of the BNC output end is electrically connected with the output terminal far away from the filter capacitor C1 to form an output L.

Through above-mentioned technical scheme, establish ties in coaxial cable signal line, it is simple to use, and the signal of low potential surrounds the signal of high potential, does benefit to the transmission of protection high potential signal, promotes the interference killing feature.

Further, a 0 ohm winding resistor R1 is electrically connected between the BNC input end and the filter capacitor C1, and the winding resistor R1 is responsive to the high-frequency signal.

Through the technical scheme, the winding resistor R1 can enable normal signals to pass through, impact components in the signals can be effectively restrained, and the circuit is protected.

Further, the outer shell of the filter capacitor C1 is grounded, and the ground wire surrounds the filter capacitor C1.

Through above-mentioned technical scheme, the entering that the shell ground connection can shield outside electromagnetic interference to a certain extent, with inside electromagnetic interference's overflow, simultaneously, when filter capacitor C1 punctures the back, can be with the signal access ground in the filter capacitor C1, avoid electric leakage to damage rear end or front end device, improve the security.

Further, the casing of the common-mode inductor L1 is grounded, and the ground wire surrounds the common-mode inductor L1.

Through above-mentioned technical scheme, the entering that the shell ground connection can shield outside electromagnetic interference to a certain extent, with inside electromagnetic interference's overflow, simultaneously, when common mode inductance L1 punctures the back, can be with the signal access ground in the common mode inductance L1, avoid electric leakage to damage rear end or front end device, improve the security.

Furthermore, a filter capacitor C2 and a 0 ohm winding resistor R2 are connected in series on the line of the output H, and the filter capacitor C2, the winding resistor R2, the filter capacitor C1 and the winding resistor R1 are symmetrical on two sides of the common mode inductor L1.

Through the technical scheme, the filter capacitor C1 and the winding resistor R1 block high-frequency signals and direct-current signals, the filter capacitor C1 and the winding resistor R1 perform primary filtering, and the filter capacitor C2 and the winding resistor R2 perform secondary filtering, so that the filtering is refined.

Compared with the prior art, the beneficial effects of the utility model are that: the winding resistor R1 can allow normal signals to pass through, impact components in the signals can be effectively inhibited, the filter capacitor C1 filters the signals, the common-mode inductor L1 is used as the mutual inductor T1, isolation can be achieved, common-mode inhibition can be achieved, the purity and safety of the signals are improved, the partial discharge background amplification caused by multipoint grounding is inhibited, and the background noise of a partial discharge system is effectively reduced.

Drawings

Fig. 1 is a circuit diagram of the present invention.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and examples.

Examples

An input signal isolation filter device for partial discharge is shown in fig. 1, and includes a BNC input terminal using a coaxial cable signal line, where the coaxial cable signal line includes an inner axial connector and an outer axial connector. The outer shaft connector at the BNC input end is grounded, the inner shaft connector is electrically connected with a 0 ohm winding resistor R1, and the winding resistor R1 responds to a high-frequency signal. One end of the winding resistor R1 far away from the BNC input end is electrically connected with a filter capacitor C1, the shell of the filter capacitor C1 is grounded, and the ground wire surrounds the filter capacitor C1. One end of the filter capacitor C1 far away from the BNC input end is electrically connected with a transformer T1, a transformer T1 is arranged as a common-mode inductor L1, the shell of the common-mode inductor L1 is grounded, and the ground wire surrounds the common-mode inductor L1. The common mode inductor L1 has 2 input terminals and 2 output terminals, the filter capacitor C1 is electrically connected with 1 of the input terminals, and the other input terminal is grounded.

The common mode inductor L1 is electrically connected to a BNC output terminal using a coaxial cable signal line, and the BNC output terminal has two terminals and is electrically connected to two output terminals of the transformer T1 in a one-to-one correspondence. Two terminals of the output end of the BNC are an inner shaft connector and an outer shaft connector, the inner shaft connector of the output end of the BNC is electrically connected with an output terminal close to the filter capacitor C1 to form an output H, and the outer shaft connector of the output end of the BNC is electrically connected with an output terminal far away from the filter capacitor C1 to form an output L. The filter capacitor C2 and the 0-ohm winding resistor R2 are connected in series on the line of the output H, and the filter capacitor C2, the winding resistor R2, the filter capacitor C1 and the winding resistor R1 are symmetrical on two sides of the common-mode inductor L1.

The circuit is connected in series with the coaxial cable signal wire, the use is simple, and the signal of the low potential surrounds the signal of the high potential, which is beneficial to protecting the transmission of the signal of the high potential and improving the anti-interference performance. The winding resistor R1 can allow normal signals to pass through, effectively inhibit impact components in the signals and protect the circuit. The filter capacitor C1 filters signals, and the mutual inductor T1 electrically isolates the signals, so that the local discharge background caused by multipoint grounding is inhibited from being enlarged, and the background noise of the local discharge system is effectively reduced. The common-mode inductor L1 is used as a mutual inductor T1, so that isolation and common-mode rejection can be realized, and the purity and safety of signals are improved. The shell ground connection can shield outside electromagnetic interference's entering to a certain extent, with inside electromagnetic interference's overflowing, simultaneously, when filter capacitor C1 or common mode inductance L1 puncture the back, can be with the signal access ground in filter capacitor C1 or the common mode inductance L1, avoid electric leakage to damage rear end or front end device, improve the security. The filter capacitor C1 and the winding resistor R1 block high-frequency signals and direct-current signals, the filter capacitor C1 and the winding resistor R1 perform primary filtering, and the filter capacitor C2 and the winding resistor R2 perform secondary filtering, so that the filtering is refined.

It is above only the utility model discloses a preferred embodiment, the utility model discloses a scope of protection does not only confine above-mentioned embodiment, the all belongs to the utility model discloses a technical scheme under the thinking all belongs to the utility model discloses a scope of protection. It should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. An input signal isolation and filtering device for partial discharge is characterized by comprising a BNC input end, wherein one end of the BNC input end is grounded, the other end of the BNC input end is electrically connected with a filtering capacitor C1, one end, far away from the BNC input end, of a filtering capacitor C1 is electrically connected with a mutual inductor T1, 2 input terminals and 2 output terminals are arranged in the mutual inductor T1, the filtering capacitor C1 is electrically connected with 1 input terminal, and the other input terminal is grounded;

2. The partial discharge input signal isolation filter apparatus of claim 1, wherein the transformer T1 is configured as a common mode inductor L1.

3. The partial discharge input signal isolation filter apparatus according to claim 2, wherein the BNC input terminal and the BNC output terminal are configured as a coaxial cable signal line, the coaxial cable signal line comprises an inner connector and an outer connector, the inner connector of the BNC input terminal is electrically connected to the filter capacitor C1, and the outer connector of the BNC input terminal is grounded; the inner connector of the BNC output end is electrically connected with the output terminal close to the filter capacitor C1 to form an output H, and the outer connector of the BNC output end is electrically connected with the output terminal far away from the filter capacitor C1 to form an output L.

4. The partial discharge input signal isolation filter device according to claim 3, wherein a 0 ohm wire winding resistor R1 is electrically connected between said BNC input terminal and said filter capacitor C1, and said wire winding resistor R1 is responsive to high frequency signals.

5. The partial discharge input signal isolation filter device of claim 1, wherein the outer shell of the filter capacitor C1 is grounded, and a ground line surrounds the filter capacitor C1.

6. The partial discharge input signal isolation filter device of claim 2, wherein the housing of the common-mode inductor L1 is grounded, and a ground line surrounds the common-mode inductor L1.

7. The device as claimed in claim 4, wherein a filter capacitor C2 and a 0 ohm winding resistor R2 are connected in series on the line of the output H, and the filter capacitor C2 and the winding resistor R2 are symmetrical with the filter capacitor C1 and the winding resistor R1 on both sides of the common mode inductor L1.