CN103645427A - Multipath partial discharge signal parallel connection method and apparatus - Google Patents

Abstract

The present application discloses a method and device for parallel connection of multiple partial discharge signals. The method includes: receiving signals input by multiple partial discharge sensors, performing preprocessing on each signal, and isolating the preprocessed signals. The signal can be self-triggered for one-way transmission, and finally the isolated signals of each channel are output. The method isolates and processes multi-channel signals, so that the signals can self-trigger one-way transmission and isolation, thereby realizing interference-free parallel connection of multiple partial discharge signals, and further avoiding signal loss during signal transmission. At the same time, since the partial discharge signals connected in parallel are all transmitted to the signal bus, one data acquisition device monitors multiple signals at the same time, thereby realizing data acquisition through the same set of data acquisition devices and reducing costs.

Description

A method and device for parallel connection of multiple partial discharge signals

technical field

The present application relates to the technical field of signal control, in particular to a method and device for parallel connection of multiple partial discharge signals.

Background technique

In partial discharge signal detection, multiple partial discharge signals are connected in parallel to one transmission bus for transmission. At the interface where any one is merged into the transmission bus, it is necessary to realize the transmission of the merged signal to the transmission bus without loss. The ground isolates the transmission of other signals on the transmission bus to the transmission line.

In the prior art, a circulator is generally used to implement unidirectional signal transmission. As shown in Figure 1, the circulator can realize the one-way transmission of the signal, but the isolation of the reverse signal is realized by absorbing the signal energy. That is to say, in the circulator, the signal can only be transmitted in the direction of 1→2, 2→3, 3→4, 4→1, and for the non-selective transmission signal in the multiplex transmission signal, that is, the parallel transmission in the signal bus The signal energy of other signals transmitted by the connecting branch is attenuated by 50%.

In addition, although the general switch can realize the isolation of multiple partial discharge signals to a certain extent, it needs manual control. When the switch is closed, the signal can pass through, and it is bidirectional. When the switch is turned off, the signal cannot pass through.

Because the switch can not be controlled by the self-triggering closing and closing of the signal in the prior art, so the self-triggering one-way transmission cannot be realized, and the one-way transmission circuit based on the circulator will generate a large number of signals when the signal passes through the signal isolation circuit Energy attenuation, resulting in signal loss.

Contents of the invention

In view of this, the embodiment of the present application provides a method and device for parallel connection of multiple partial discharge signals, which can realize self-triggered one-way transmission and isolation of signals, and then realize interference-free parallel connection of multiple partial discharge signals, avoiding signal transmission losses in the process.

In order to achieve the above objectives, the technical solutions provided in the embodiments of the present application are as follows:

A method for parallel connection of multiple partial discharge signals, comprising:

Receive input signals from multiple partial discharge sensors;

Preprocessing each of the signals to obtain a preprocessed signal;

performing isolation processing on the preprocessed signal, so that the signal can be self-triggered for one-way transmission;

Output the signals after each isolation process.

Preferably, said isolating said preprocessed signal includes:

dividing the preprocessed signal into a first sub-signal and a second sub-signal;

Delayed transmission of the first sub-signal after a set delay time;

The second sub-signal is compared with a reference level to realize automatic signal detection, and the second sub-signal is converted into a driving signal of a self-triggering switch;

The drive signal is extended to a set time width to drive the self-trigger switch to be turned on and off.

Preferably, the reference level is an adjustable reference level.

Preferably, the driving signal is a driving signal with a constant voltage and a pulse width consistent with the input signal.

Preferably, the delay time is realized by passing signals through multiple emitter follower circuits.

A device for parallel connection of multiple partial discharge signals, comprising:

The signal input interface is used to receive signals input by multiple partial discharge sensors;

a signal preprocessing circuit connected to the signal input interface at the input end, for preprocessing each of the signals to obtain a preprocessed signal;

a signal isolation circuit whose input terminal is connected to the output terminal of the signal processing circuit, and is used for isolating the preprocessed signal so that the signal can be self-triggered for one-way transmission;

The signal output interface connected to the output end of the signal isolation circuit is used to output the signals after isolation processing from each channel.

Preferably, the signal isolation circuit includes:

a signal separation circuit, configured to divide the preprocessed signal into a first sub-signal and a second sub-signal;

a signal delay circuit connected to the output end of the signal separation circuit, for delaying transmission of the first sub-signal after a set delay time;

A high-speed comparison circuit connected to the output terminal of the signal separation circuit and connected in parallel with the signal delay circuit is used to compare the second sub-signal with a reference level to realize automatic detection of the signal, and compare the second sub-signal The second sub-signal is transformed into a driving signal of a self-triggering switch;

a reference voltage circuit whose output terminal is connected to the high-speed comparison circuit, and is used to provide the reference level;

A monostable trigger circuit connected to the output terminal of the high-speed comparison circuit, used to widen the drive signal to a set time width to drive the self-trigger switch to be turned on and off;

A self-trigger switch connected to the output terminals of the delay circuit and the monostable trigger circuit respectively is used to control the output of the signal.

Preferably, the reference level is an adjustable reference level.

Preferably, the driving signal is a driving signal with a constant voltage and a pulse width consistent with the input signal.

Preferably, the delay time is realized by using a plurality of emitter follower circuits in which the signal passes through the signal delay circuit.

It can be seen from the above technical solutions that the method and device for parallel connection of multiple partial discharge signals provided by the embodiment of the present application will receive signals input by multiple partial discharge sensors and perform preprocessing on each of the signals. The final signal is isolated and processed, so that the signal can be self-triggered for one-way transmission, and finally the isolated signal of each channel is completely output. Compared with the prior art, the present invention pre-processes and isolates multi-channel signals, so that the signals can self-trigger one-way transmission and isolation, and then realize the interference-free parallel connection of multiple partial discharge signals, further avoiding the transmission Signal loss during signal processing.

At the same time, since the partial discharge signals connected in parallel are all transmitted to the signal bus, one data acquisition device can monitor multiple signals at the same time, thereby realizing data acquisition through the same set of data acquisition devices, achieving multiple Synchronous online monitoring of power equipment, timely detection of insulation defects of power equipment, and the purpose of improving equipment operation safety.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments described in this application. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a schematic diagram of signal transmission of a circulator in the prior art;

Fig. 2 is a flow chart of a method for parallel connection of multiple partial discharge signals provided by an embodiment of the present application;

FIG. 3 is a flow chart of isolating preprocessed signals provided by an embodiment of the present application;

Fig. 4 is a schematic diagram of a parallel connection device for multiple partial discharge signals provided by an embodiment of the present application;

FIG. 5 is a schematic diagram of a signal isolation circuit provided by an embodiment of the present application;

FIG. 6 is a schematic diagram of a signal isolation circuit provided by an embodiment of the present application.

Detailed ways

In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described The embodiments are only some of the embodiments of the present application, but not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the scope of protection of this application.

Embodiment one:

Fig. 2 is a flow chart of a method for parallel connection of multiple partial discharge signals provided by an embodiment of the present application.

As shown in Figure 2, the method includes:

Step S201: Receive signals input by a plurality of partial discharge sensors.

Specifically, the partial discharge sensor in this step is a sensor that can generate signals such as UHF signals, ultrasonic signals or high-frequency current signals, so the received signals can be UHF signals, ultrasonic signals or high-frequency current signals Wait for the signal.

Step S202: Perform preprocessing on each signal to obtain a preprocessed signal.

In this step, specifically, if the signal is a UHF signal, its preprocessing includes related steps such as amplification, filtering, and detection (that is, down-frequency processing of the UHF signal); when the signal is another type of signal When , the preprocessing of the signal only needs to amplify and filter the signal, and there is no need to perform frequency reduction processing such as detection.

Step S203: Perform isolation processing on the preprocessed signal.

In order to avoid mutual interference between multiple signals during signal transmission, the pre-processed signals are isolated, so that the signals can be self-triggered for one-way transmission. The specific isolation process is shown in FIG. 3. FIG. 3 is a flow chart of isolating the pre-processed signal provided by the embodiment of the present application. The isolation process of the pre-processed signal includes:

Step S301: Divide the preprocessed signal into a first sub-signal and a second sub-signal.

Step S302: Delayed transmission of the first sub-signal after a set delay time.

Specifically, the delay time is greater than the sum of the self-trigger switch control circuit and the self-trigger switch action time, and the delay time is realized by passing signals through multiple emitter follower circuits. The emitter follower circuit not only maintains the integrity of the signal, but also realizes the delayed transmission of the signal through the series connection of multiple emitter follower circuits, and can adjust the delay time according to the series connection of the emitter follower circuits. The number of follower circuits is not limited here, and can be selected and connected in series according to specific conditions.

Step S303: The second sub-signal is compared with the reference level to realize automatic detection of the signal, and the second sub-signal is converted into a driving signal of the self-triggering switch.

Specifically, the reference level is an adjustable reference level that has been set. It can be adjusted according to the specific situation when setting. The second sub-signal is compared with the reference level to realize automatic signal detection, level conversion, and conversion It is a signal with constant voltage and pulse width consistent with the input signal.

Step S304: Extend the drive signal to a set time width to drive the self-trigger switch on and off.

Step S204: Outputting the isolated signals of each channel.

At this time, after a certain time delay, the first sub-signal arrives at the self-triggering switch just at the same time as the second sub-signal, thereby ensuring that the partial discharge signal can completely pass through the self-triggering switch, realizing the self-triggering one-way transmission of the signal, Furthermore, the interference-free parallel connection of multiple partial discharge signals is realized, and the loss in the signal transmission process is avoided.

It can be seen from the above technical solutions that the method for parallel connection of multiple partial discharge signals provided by the embodiment of the present application receives signals input from multiple partial discharge sensors and performs preprocessing on each of the signals, and the preprocessed The signal is isolated and processed so that the signal can be self-triggered for one-way transmission, and finally the isolated signal of each channel is completely output. Compared with the prior art, the present invention pre-processes and isolates multi-channel signals, so that the signals can self-trigger one-way transmission and isolation, and then realize the interference-free parallel connection of multiple partial discharge signals, further avoiding the transmission Signal loss during signal processing.

At the same time, in the parallel connection method of multiple partial discharge signals, since the partial discharge signals connected in parallel are all transmitted to the signal bus, one data acquisition device can monitor multiple signals at the same time, thereby realizing data acquisition through the same set of data acquisition devices , to achieve synchronous online monitoring of multiple power equipment at a lower cost, to detect insulation defects of power equipment in time, and to improve the safety of equipment operation.

Embodiment two:

On the basis of Embodiment 1, the embodiment of the present application also provides a parallel connection device for multiple partial discharge signals, as shown in Figure 4, which is a schematic diagram of a parallel connection device for multiple partial discharge signals provided by the embodiment of the present application .

The unit includes:

The signal input interface 401 is used for receiving signals input by a plurality of partial discharge sensors.

Specifically, the partial discharge sensor is a sensor that can generate signals such as ultra-high frequency signals, ultrasonic signals, or high-frequency current signals. Therefore, the received signals can be signals such as ultra-high frequency signals, ultrasonic signals, or high-frequency current signals.

The signal input interface 401 is a radio frequency signal interface, connected to the partial discharge sensor, and the frequency influence range is 300MHz to 1.5GHz.

The signal preprocessing circuit 402, whose input end is connected to the signal input interface 401, is used to preprocess each signal to obtain a preprocessed signal.

Specifically, if the signal is a UHF signal, its preprocessing includes related steps such as amplification, filtering, and detection (that is, down-frequency processing of the UHF signal); when the signal is another type of signal, the signal The preprocessing of the signal only needs to amplify and filter the signal, and there is no need to perform frequency reduction processing such as detection.

Among them, a low-noise amplifier is needed to amplify the signal, and its amplification gain is greater than or equal to 20dB, and the frequency response range is 300MHz to 3GHz.

The signal isolation circuit 403, whose input terminal is connected to the output terminal of the signal preprocessing circuit 402, is used for isolating the preprocessed signal, so that the signal can be self-triggered and unidirectionally transmitted.

In order to avoid mutual interference between multiple signals during signal transmission, the preprocessed signal is isolated by the signal isolation circuit 403 . As shown in FIG. 5, FIG. 5 is a schematic diagram of a signal isolation circuit provided in the embodiment of the present application, and the signal isolation circuit 403 includes:

The signal separation circuit 501 is configured to divide the preprocessed signal into a first sub-signal and a second sub-signal.

The signal delay circuit 502 is connected to the output terminal of the signal separation circuit 501, and is used for delaying the transmission of the first sub-signal after a set delay time.

Specifically, the signal delay circuit 502 is a multi-stage emitter-follower circuit connected in series, and the frequency response ranges from 300 MHz to 3 GHz, wherein the time delay of the first-stage follower circuit is greater than 10 ns. The delay time of the signal delay circuit 502 is greater than the sum of the self-trigger switch control circuit and the self-trigger switch action time, and the delay time is realized by passing the signal through multiple emitter follower circuits set in the signal delay circuit. The emitter follower circuit not only maintains the integrity of the signal, but also realizes the delayed transmission of the signal through the series connection of multiple emitter follower circuits, and can adjust the delay time according to the series connection of the emitter follower circuits. The number of follower circuits is not limited here, and can be selected and connected in series according to specific conditions.

The output terminal of the reference voltage circuit 503 is connected to the high-speed comparison circuit 504 for providing a reference level.

Specifically, the reference level is a set adjustable reference level, which is provided by the reference voltage circuit 503. When the reference voltage circuit 503 sets the reference level, it can be adjusted according to the specific situation, and adjusted to produce the required reference level. until.

The high-speed comparator circuit 504 is connected to the output terminal of the signal separation circuit 501, and is connected in parallel with the signal delay circuit 502, and is used to compare the second sub-signal with the reference level provided by the reference voltage circuit 503 to realize the automatic detection of the signal, and The second sub-signal is transformed into a driving signal of the self-triggering switch.

Specifically, the second sub-signal is compared with the reference level to realize automatic detection of the signal, and the level conversion is performed to convert the signal into a signal with a constant voltage and a pulse width consistent with the input signal.

The monostable trigger circuit 505 is connected to the output terminal of the high-speed comparator circuit 504 and is used to widen the driving signal to a set time width to drive the self-triggering switch 506 to be turned on and off.

Wherein, the monostable trigger circuit 505 is a monostable trigger circuit based on a 555 timer, and the transient stable state time is less than 1 us. The action time of the self-triggering switch 506 is less than 10 ns.

The self-triggering switch 506 respectively connected to the output terminals of the delay circuit 502 and the monostable trigger circuit 505 is used for outputting control signals.

The self-trigger switch 506 is turned on or off according to the extended drive signal output by the monostable trigger circuit 505 , so as to control the output of the complete signal and realize the unidirectional transmission of the signal.

The signal output interface 404 is connected to the output terminal of the signal isolation circuit 403 and is used for outputting the isolated signals of each channel.

The signal output interface 404 is also a radio frequency signal interface, and its frequency response ranges from 300MHz to 1.5GHz.

At this time, the first sub-signal is delayed for a certain period of time by the signal delay circuit 502, and arrives at the self-triggering switch at the same time as the second sub-signal, thereby ensuring that the multiple partial discharge signals pass through the self-triggering switch completely, realizing signal The self-triggering one-way transmission realizes the interference-free parallel connection of multiple partial discharge signals, avoiding the loss in the signal transmission process.

Referring to FIG. 6, FIG. 6 is a schematic diagram of a signal isolation circuit provided by the embodiment of the present application. The signal is input through the signal input interface, and is divided into two paths after being preprocessed by the signal preprocessing circuit. One path is connected to the reference voltage circuit 503 The generated adjustable level is compared by the high-speed comparison circuit 504 to realize the automatic detection of the signal. After level conversion, it becomes a driving signal of a self-triggering switch with a constant voltage and a pulse width consistent with the input signal. The driving signal output by the high-speed comparison circuit 504 is extended to a set time width by the monostable trigger circuit 505 to drive the self-trigger switch 506 to automatically turn on, and automatically turn off after a set time delay. In order to ensure that the signal completely passes through the self-trigger switch, the signal preprocessed by the signal preprocessing circuit has undergone a certain delay on the other way, and the delay time is greater than the sum of the control circuit of the self-trigger switch 506 and the action time of the self-trigger switch 506. Time-to-time use of signals through a plurality of emitter-follower circuits 601 to achieve. The emitter follower circuit 601 can not only maintain the integrity of the signal, but also realize the extension and adjustment of the time delay through the series connection of the number of emitter follower circuits 601, so that the partial discharge signal can completely pass through the self-triggering switch.

It can be seen from the above technical solutions that the multi-channel partial discharge signal parallel connection device provided by the embodiment of the present application receives signals input from a plurality of partial discharge sensors and performs preprocessing on each of the signals, and converts the preprocessed signals to Isolation processing is carried out so that the signal can be self-triggered for one-way transmission, and finally the signals after isolation processing of each channel are completely output. Compared with the prior art, the present invention pre-processes and isolates multi-channel signals, so that the signals can self-trigger one-way transmission and isolation, and then realize the interference-free parallel connection of multiple partial discharge signals, further avoiding the transmission Signal loss during signal processing.

At the same time, in the parallel connection device for multiple partial discharge signals, since the partial discharge signals connected in parallel are all transmitted to the signal bus, one data acquisition device can monitor multiple signals at the same time, thereby realizing data acquisition through the same set of data acquisition devices. Realize synchronous online monitoring of multiple power equipment at a lower cost, discover insulation defects of power equipment in time, and improve equipment operation safety.

It should also be noted that in this article, relational terms such as first and second etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that these entities or operations Any such actual relationship or order exists between. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A method for parallel connection of multiple partial discharge signals, characterized in that, comprising: Receive input signals from multiple partial discharge sensors; Preprocessing each of the signals to obtain a preprocessed signal; performing isolation processing on the preprocessed signal, so that the signal can be self-triggered for one-way transmission; Output the signals after each isolation process. 2. The method according to claim 1, wherein said isolating said preprocessed signal comprises: dividing the preprocessed signal into a first sub-signal and a second sub-signal; Delayed transmission of the first sub-signal after a set delay time; The second sub-signal is compared with a reference level to realize automatic signal detection, and the second sub-signal is converted into a driving signal of a self-triggering switch; The drive signal is extended to a set time width to drive the self-trigger switch to be turned on and off. 3. The method according to claim 2, wherein the reference level is an adjustable reference level. 4. method according to claim 2, is characterized in that, described drive signal is voltage constant, A signal whose pulse width matches that of the input signal. 5. The method according to claim 2, characterized in that, the delay time is realized by passing signals through a plurality of emitter follower circuits. 6. A multi-channel partial discharge signal parallel connection device, characterized in that it comprises: The signal input interface is used to receive signals input by multiple partial discharge sensors; a signal preprocessing circuit whose input terminal is connected to the signal input interface, and is used to preprocess each of the signals to obtain a preprocessed signal; a signal isolation circuit whose input terminal is connected to the output terminal of the signal preprocessing circuit, and is used for isolating the preprocessed signal, so that the signal can be self-triggered and unidirectionally transmitted; The signal output interface connected to the output end of the signal isolation circuit is used to output the signals after isolation processing from each channel. 7. The device according to claim 6, wherein the signal isolation circuit comprises: a signal separation circuit, configured to divide the preprocessed signal into a first sub-signal and a second sub-signal; a signal delay circuit connected to the output end of the signal separation circuit, for delaying transmission of the first sub-signal after a set delay time; A high-speed comparison circuit connected to the output terminal of the signal separation circuit and connected in parallel with the signal delay circuit is used to compare the second sub-signal with a reference level to realize automatic detection of the signal, and compare the second sub-signal The second sub-signal is transformed into a driving signal of a self-triggering switch; a reference voltage circuit whose output terminal is connected to the high-speed comparison circuit, and is used to provide the reference level; A monostable trigger circuit connected to the output terminal of the high-speed comparison circuit, used to widen the drive signal to a set time width to drive the self-trigger switch to be turned on and off; A self-trigger switch connected to the output terminals of the delay circuit and the monostable trigger circuit respectively is used to control the output of the signal. 8. The device according to claim 7, wherein the reference level is an adjustable reference level. 9. The device according to claim 7, wherein the driving signal is a signal with a constant voltage and a pulse width consistent with the input signal. 10 . The device according to claim 7 , wherein the delay time is realized by using a plurality of emitter follower circuits in which the signal passes through a signal delay circuit. 11 .

Images