CN202119872U - Intelligent switch cabinet partial discharge detection device based on ultrasonic signals - Google Patents
Intelligent switch cabinet partial discharge detection device based on ultrasonic signals Download PDFInfo
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- CN202119872U CN202119872U CN2011202449712U CN201120244971U CN202119872U CN 202119872 U CN202119872 U CN 202119872U CN 2011202449712 U CN2011202449712 U CN 2011202449712U CN 201120244971 U CN201120244971 U CN 201120244971U CN 202119872 U CN202119872 U CN 202119872U
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- ultrasonic signal
- local discharge
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Abstract
Disclosed is an intelligent switch cabinet partial discharge detection device based on ultrasonic signals, comprising: a plurality of ultrasonic sensors arranged upon the intelligent switch cabinet body, a plurality of ultrasonic preamplifiers correspondingly connected with the ultrasonic sensors and sending out the ultrasonic signals received from ultrasonic sensors after amplifying the ultrasonic signals, a data acquisition system which, with a plurality of data acquisition channels, is connected with the ultrasonic preamplifiers and acquires the ultrasonic signals transmitted by the ultrasonic preamplifiers and is arranged near the intelligent switch cabinet, and a server which is long-distance arranged away from the intelligent switch cabinet and is connected with the data acquisition system via an optical cable and realizes data transmission, wherein the server consists of a data processing module and a partial discharge signal characteristic database; and the data processing module processes the received signals and then sends the processed signals into the partial discharge signal characteristic database.
Description
Technical field
The utility model relates to a kind of local discharge signal pick-up unit, relates in particular to a kind of local discharge signal pick-up unit of intelligent switchboard.
Background technology
Switch cubicle is the visual plant in the electrical power distribution system, and insulation fault is one of important hidden danger of serious threat switch cubicle safe operation.
A large amount of switch cubicle fault statistics analyses show that shelf depreciation is to cause the main cause of switch cubicle insulation fault, and in addition, shelf depreciation also is the important sign of insulation degradation.Therefore, detect shelf depreciation and can find the inner insulation fault defective that exists of switch cubicle timely and effectively.
Shelf depreciation as a kind of important means of high voltage electric power equip ment insulating monitoring and diagnosis, is extensively promoted and is used in electric system at present.Therefore, existing in the market based on several different methods, be applicable to the local discharge detection device of multiple power equipment.For switch cubicle; Because near the environment the switch cubicle is more abominable; Traditional industrial computer data acquisition system (DAS) that is used for Partial Discharge Detection must be placed on the place that certain distance is arranged apart from switch cubicle; This just causes in the transport process of simulating signal, can introducing a large amount of the interference, thereby has influenced testing result.
Summary of the invention
The purpose of the utility model provides a kind of intelligent switchboard local discharge detection device based on ultrasonic signal; This local discharge detection device adopts sonac to catch local discharge signal; Make its this local discharge detection device have good anti-interference than existing local discharge detection device; Also have good shelf depreciation point location ability simultaneously, the related local discharge detection device of the utility model is also through adopting Embedded data acquisition system (DAS) to improve its interference free performance in addition.
In order to realize the foregoing invention purpose, the utility model provides a kind of intelligent switchboard local discharge detection device based on ultrasonic signal, and it comprises:
Several sonacs, it is affixed on the cabinet of intelligent switchboard;
Several ultrasonic prime amplifiers, its respectively with the corresponding connection of said each sonac, see off after the ultrasonic signal that is received from sonac amplified;
One has the data acquisition system (DAS) of several data acquisition channels, and it is connected with said each ultrasonic prime amplifier, gathers the ultrasonic signal of each ultrasonic prime amplifier transmission, and said data acquisition system (DAS) is arranged near the intelligent switchboard;
One server; It is apart from the long-range setting of intelligent switchboard; Said server is connected through optical cable with said data acquisition system (DAS) and realizes data transmission; Said server comprises a data processing module and a local discharge signal property data base, and said data processing module is sent it into the local discharge signal property data base after the signal of its reception is handled.
Preferably; In the intelligent switchboard local discharge detection device based on ultrasonic signal, the frequency band breadth extreme of said sonac is 20～180kHz, and resonance frequency is 30kHz; Sensitivity be 85 [75] V/ (m/s) [V/ubar] (dB), the output signal is a differential signal.
Preferably; In intelligent switchboard local discharge detection device based on ultrasonic signal; Be provided with a butter layer between the cabinet of said intelligent switchboard and said each sonac, promptly adopt butter to be coupled between the cabinet of sonac and switch cubicle, can obtain better ultrasonic signal like this.
The described intelligent switchboard local discharge detection device based on ultrasonic signal of the utility model is when carrying out Partial Discharge Detection; Sonac lock-on signal by the applying switch cabinet body; And transmit it to ultrasonic prime amplifier and carry out processing and amplifying; Be transferred to data acquisition system (DAS) by ultrasonic prime amplifier then and carry out data acquisition, because this data acquisition system (DAS) is arranged near the switch cubicle, the distance between itself and the sonac is short; The route that is sonac transmission data is not long, so the external disturbance that the data of sonac transmission receive also can reduce greatly.Data acquisition system (DAS) is transferred to the data that collect the server of long-range setting through optical cable; Carry out anti-interference process to the received signal and extract characteristic parameter by the data in server processing module; Then deposit the local discharge signal property data base in, expert system and then make the diagnosis of switch cubicle state of insulation according to the historical data in the property data base.
Preferably, for the further antijamming capability that improves the speed of data acquisition and improve data acquisition system (DAS), in the described intelligent switchboard local discharge detection device based on ultrasonic signal of the utility model, said data acquisition system (DAS) comprises:
One mainboard which is provided with several first bus slots and one second bus slot;
Several have the AD sampling plate of bus, and its difference corresponding inserted is connected with said mainboard through bus in said each first bus slot, and wherein each AD sampling plate is gathered at least one road ultrasonic signal;
One has the DSP signal-processing board of bus; It is inserted in said second bus slot; Through being connected of bus and mainboard to realize and being connected and data transmission of each AD sampling plate; Said DSP signal-processing board is provided with a dsp chip and a TCP/IP interface, and said dsp chip receives the data of each AD sampling plate transmission, and it is transferred to said server through the TCP/IP interface with the said optical cable that is connected with the TCP/IP interface.
Wherein, said each AD sampling plate includes:
At least one signal amplifier, it amplifies the ultrasonic signal that receives;
At least one low-pass filter, itself and the corresponding connection of said at least one signal amplifier are with said ultrasonic signal filtering;
At least one RF coupler, its corresponding connection with at least one low-pass filter transfers out after will passing through the ultrasonic signal isolation processing of filtering;
One AD chip, it comprises at least one AD converter, the corresponding connection of said at least one AD converter with at least one RF coupler, the ultrasonic signal of said AD chip RF coupling device transmission is sampled;
One programming device, it is connected with said AD chip, and said programming device control AD chip begins to sample, and said programming device also is connected with the bus of said AD sampling plate;
One buffer memory element, it is connected respectively with the AD chip with said programming device, and said programming device control AD chip transfers to the buffer memory element with sampled data and carries out buffer memory.
Preferably, above-mentioned programming device is CPLD (Complex Programmable Logic Device, CPLD) or FPGA (Field-Programmable Gate Array, field programmable gate array).Above-mentioned buffer memory element is a SRAM (Static RAM) storage array.
Preferably, the quantity of said signal amplifier, low-pass filter and RF coupler is two, and said AD chip comprises two AD converters.Be that each AD sampling plate has two acquisition channels, the corresponding two paths of signals of gathering.
In the described intelligent switchboard local discharge detection device of the utility model based on ultrasonic signal, also be provided with a power supply on the mainboard in the above-mentioned data acquisition system (DAS), it is connected with the DSP signal-processing board with said each AD sampling plate, is its power supply; Also be provided with a synchronous sampling control signal on the said mainboard and produce circuit, it is connected with each AD sampling plate, controls its synchronized sampling.
Above-mentioned data acquisition system (DAS) is when carrying out data acquisition to ultrasonic signal; Receive the ultrasonic signal of ultrasonic prime amplifier transmission by the AD sampling plate; And it is amplified, filtering, isolates these necessary signal conditions and handle; Carry out data sampling by the AD chip in the AD sampling plate then, the data that collect: can read in by programming device control and carry out Filtering Processing in the programming device, write the buffer memory element by programming device control then; By the buffer memory element data of gathering are carried out buffer memory, wait for that the data processing equipment of rear end is taken the data of gathering away; Also can control the buffer memory element that writes direct by the programming device; By the buffer memory element data of gathering are carried out buffer memory; The DSP signal-processing board that wait is connected with the AD sampling plate is taken data in buffer away; The dsp chip data that will be received from the transmission of each AD sampling plate transfer to server through the TCP/IP interface with the optical cable that is connected with the TCP/IP interface then, are further handled by server.
The described intelligent switchboard local discharge detection device based on ultrasonic signal of the utility model makes it than existing local discharge signal owing to adopted technique scheme, has the following advantages:
1. the described intelligent switchboard local discharge detection device based on ultrasonic signal of the utility model is owing to adopted sonac and corresponding kit; And make this local discharge detection device have good anti-interference, also have good shelf depreciation point location ability simultaneously;
2. the utility model is described short based on the data transmission distance between data acquisition system (DAS) and the sonac in the intelligent switchboard local discharge detection device of ultrasonic signal, thereby has improved the anti-interference of this local discharge detection device;
3. in the preferred version of the utility model; Data acquisition system (DAS) is owing to adopted AD sampling plate and DSP signal-processing board to be plugged in the damascene structures on the mainboard; Make that a mainboard can integrated a plurality of AD sampling plates; Thereby improved acquisition speed greatly, also reduced the volume of data acquisition system (DAS).
Description of drawings
Fig. 1 is the described intelligent switchboard local discharge detection device structured flowchart in one embodiment based on ultrasonic signal of the utility model.
Fig. 2 is the sensitivity calibration curve of the described sonac that is adopted in one embodiment based on the intelligent switchboard local discharge detection device of ultrasonic signal of the utility model.
Fig. 3 is the structured flowchart of the AD sampling plate of the described data acquisition system (DAS) that adopts in one embodiment based on the intelligent switchboard local discharge detection device of ultrasonic signal of the utility model.
Fig. 4 is the structured flowchart at the DSP signal-processing board of the described data acquisition system (DAS) that adopts in one embodiment based on the intelligent switchboard local discharge detection device of ultrasonic signal of the utility model.
Embodiment
Come the described intelligent switchboard local discharge detection device based on ultrasonic signal of the utility model is further specified below in conjunction with accompanying drawing and specific embodiment.
As shown in Figure 1, the intelligent switchboard local discharge detection device based on ultrasonic signal in the present embodiment comprises: a plurality of sonacs 2, and it is affixed on the cabinet 1 of intelligent switchboard, adopts the good quality butter coupling between sonac 2 and the cabinet 1; Several ultrasonic prime amplifiers 3 respectively with each sonac 2 corresponding connection, see off after the ultrasonic signal that is received from sonac amplified; Data acquisition system (DAS) 4 with several data acquisition channels is connected with each ultrasonic prime amplifier 3, and the ultrasonic signal that each ultrasonic prime amplifier is transmitted carries out data acquisition, and this data acquisition system (DAS) 4 is arranged near the cabinet 1; Remote server 5; It is connected through optical cable with data acquisition system (DAS) 4 and realizes data transmission; This remote server 5 carries out anti-interference process to the received signal and extracts characteristic parameter through the data processing module of being located in it; Then deposit the local discharge signal property data base in, expert system and then make the diagnosis of switch cubicle state of insulation according to the historical data in the property data base.
In the present embodiment; The highly sensitive ultrasonic sensor of D9241A type that sonac has selected for use U.S. PAC company to make; This sensor frequency band breadth extreme is 20～180kHz, and resonance frequency is 30kHz, sensitivity be 85 [75] V/ (m/s) [V/ubar] (dB); The output signal is a differential signal, and anti-interference is higher during long-distance transmissions.The sensitivity calibration curve of this sonac is as shown in Figure 2.
The data acquisition system (DAS) that adopts in the present embodiment comprises: mainboard; Have 9 bus slot and bus slots that are used to plug the DSP signal-processing board that are used to plug the AD sampling plate on the mainboard; 9 AD sampling plates and a DSP signal-processing board corresponding inserted in above-mentioned each bus slot, thereby realized interconnecting and data transmission between AD sampling plate and the DSP signal-processing board.Mainboard has power supply, thereby is AD sampling plate and the power supply of DSP signal-processing board, and in addition, mainboard carries out the synchronizing signal sampling through 9 AD sampling plates of synchronized sampling control signal generation circuit control.The AD sampling plate is given the DSP signal-processing board with the data transmission that collects; Handle by the dsp chip on the DSP signal-processing board then; Be connected with network through the TCP/IP interface of being located on the DSP signal-processing board then, and great amount of data transmission is further handled in remote server.
The structured flowchart of AD sampling plate is as shown in Figure 3 in the above-mentioned data acquisition system (DAS).This AD sampling plate can be gathered the two-way ultrasonic signal simultaneously, and it comprises: two signal amplifiers, and the differential analog signal that sonac is exported converts single-ended signal into; Two low-pass filters, its respectively with two corresponding connections of signal amplifier, single-ended signal is carried out filtering; Two RF couplers (being signal transformer), its respectively with two corresponding connections of low-pass filter, to carrying out isolation processing through the signal of filtering; AD chip with two AD converters is connected with two RF couplers, and the signal of handling through above-mentioned amplification, filtering and isolation conditioning is carried out data sampling; CPLD (or FPGA) is connected with this AD chip, and control AD chip begins to carry out data sampling, and control AD chip is put into the SRAM storage array with the data that collect and carried out buffer memory.Above-mentioned CPLD (or FPGA) can handle the image data of AD chip output flexibly; Its both can with this image data read in earlier carry out Filtering Processing among the CPLD (or FPGA) after; Again it is write the SRAM storage array and carry out buffer memory; Also can directly provide the write control signal of SRAM storage array, the image data of the AD chip output SRAM storage array that writes direct is carried out buffer memory.Therefore in the present embodiment; Between SRAM storage array, AD chip and the CPLD (or FPGA) is interconnective; And CPLD also is connected with the bus of AD sampling plate, thereby image data is further handled to the DSP signal-processing board through bus transfer.In the present embodiment, the AD sampling plate also comprises a MCU who is connected with CPLD (or FPGA) (Micro Control Unit, micro-control unit).Adopt CPLD (or FPGA) control sampling process can well improve the behavior in service of system in the present embodiment, the SRAM storage array then has the advantage of high capacity storage.
Fig. 4 is the structured flowchart of the DSP signal-processing board in the present embodiment; The DSPTMS320C6713B chip that the dsp chip of this DSP signal-processing board adopts TI company to produce: the data of 9 AD collection plate collections to the DSP signal-processing board, read and are stored in SDRAM by the DSPTMS320C6713B chip by bus transfer; The HPI mouth of DSP signal-processing board provides the communication of main frame and dsp chip; The FLASH stored programme; The data of gathering are carried out denoising, sample analysis in the DSPTMS320C6713B chip after, the network interface of being made up of W3100 and the RTL8201 raw data of will sampling is sent in the remote server and goes.
Be noted that the above specific embodiment of enumerating that is merely the utility model, obviously the utility model is not limited to above embodiment, and many similar variations are arranged thereupon.If those skilled in the art from all distortion that the disclosed content of the utility model directly derives or associates, all should belong to the protection domain of the utility model.
Claims (9)
1. the intelligent switchboard local discharge detection device based on ultrasonic signal is characterized in that, comprising:
Several sonacs, it is affixed on the cabinet of intelligent switchboard;
Several ultrasonic prime amplifiers, its respectively with the corresponding connection of said each sonac, see off after the ultrasonic signal that is received from sonac amplified;
One has the data acquisition system (DAS) of several data acquisition channels, and it is connected with said each ultrasonic prime amplifier, gathers the ultrasonic signal of each ultrasonic prime amplifier transmission, and said data acquisition system (DAS) is arranged near the intelligent switchboard;
One server; It is apart from the long-range setting of intelligent switchboard; Said server is connected through optical cable with said data acquisition system (DAS) and realizes data transmission; Said server comprises a data processing module and a local discharge signal property data base, and said data processing module is sent it into the local discharge signal property data base after the signal of its reception is handled.
2. the intelligent switchboard local discharge detection device based on ultrasonic signal as claimed in claim 1 is characterized in that said data acquisition system (DAS) comprises:
One mainboard which is provided with several first bus slots and one second bus slot;
Several have the AD sampling plate of bus, and its difference corresponding inserted is connected with said mainboard through bus in said each first bus slot, and wherein each AD sampling plate is gathered at least one road ultrasonic signal;
One has the DSP signal-processing board of bus; It is inserted in said second bus slot; Through being connected of bus and mainboard to realize and being connected and data transmission of each AD sampling plate; Said DSP signal-processing board is provided with a dsp chip and a TCP/IP interface, and said dsp chip receives the data of each AD sampling plate transmission, and it is transferred to said server through the TCP/IP interface with the said optical cable that is connected with the TCP/IP interface.
3. the intelligent switchboard local discharge detection device based on ultrasonic signal as claimed in claim 2 is characterized in that, said each AD sampling plate includes:
At least one signal amplifier, it amplifies the ultrasonic signal that receives;
At least one low-pass filter, itself and the corresponding connection of said at least one signal amplifier are with said ultrasonic signal filtering;
At least one RF coupler, its corresponding connection with at least one low-pass filter transfers out after will passing through the ultrasonic signal isolation processing of filtering;
One AD chip, it comprises at least one AD converter, said at least one AD converter with at least
One RF coupler is corresponding to be connected, and the ultrasonic signal of said AD chip RF coupling device transmission is sampled;
One programming device, it is connected with said AD chip, and said programming device control AD chip begins to sample, and said programming device also is connected with the bus of said AD sampling plate;
One buffer memory element, it is connected respectively with the AD chip with said programming device, and said programming device control AD chip transfers to the buffer memory element with sampled data and carries out buffer memory.
4. the intelligent switchboard local discharge detection device based on ultrasonic signal as claimed in claim 3 is characterized in that the quantity of said signal amplifier, low-pass filter and RF coupler is two, and said AD chip comprises two AD converters.
5. like claim 3 or 4 described intelligent switchboard local discharge detection devices, it is characterized in that also be provided with a power supply on the said mainboard, it is connected with the DSP signal-processing board with said each AD sampling plate, is its power supply based on ultrasonic signal; Also be provided with a synchronous sampling control signal on the said mainboard and produce circuit, it is connected with each AD sampling plate, controls its synchronized sampling.
6. the intelligent switchboard local discharge detection device based on ultrasonic signal as claimed in claim 3 is characterized in that, said programming device is a CPLD or a FPGA.
7. like claim 3 or 6 described intelligent switchboard local discharge detection devices, it is characterized in that said buffer memory element is a SRAM storage array based on ultrasonic signal.
8. the intelligent switchboard local discharge detection device based on ultrasonic signal as claimed in claim 1 is characterized in that, between the cabinet of said intelligent switchboard and said each sonac, also is provided with a butter layer.
9. like claim 1 or 8 described intelligent switchboard local discharge detection devices based on ultrasonic signal; It is characterized in that; The frequency band breadth extreme of said sonac is 20～180kHz; Resonance frequency is 30kHz, sensitivity be 85 [75] V/ (m/s) [V/ubar] (dB), the output signal is a differential signal.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2011202449712U CN202119872U (en) | 2011-07-12 | 2011-07-12 | Intelligent switch cabinet partial discharge detection device based on ultrasonic signals |
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| CN2011202449712U CN202119872U (en) | 2011-07-12 | 2011-07-12 | Intelligent switch cabinet partial discharge detection device based on ultrasonic signals |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102998605A (en) * | 2012-12-07 | 2013-03-27 | 山西省电力公司吕梁供电公司 | System and method for signal modulation for panoramic partial discharge monitoring of transformer substation |
| CN103675618A (en) * | 2013-11-30 | 2014-03-26 | 成都科泰地理信息技术有限公司 | Switchgear partial discharge inspecting instrument with printing function |
| CN103969556A (en) * | 2014-03-14 | 2014-08-06 | 上海交通大学 | Insulation electrified detection device for cable accessories |
| CN108919066A (en) * | 2018-05-22 | 2018-11-30 | 广西电网有限责任公司电力科学研究院 | A kind of partial discharge of switchgear detection system and detection method |
| CN111638431A (en) * | 2020-07-14 | 2020-09-08 | 国网山东省电力公司烟台供电公司 | Cubical switchboard partial discharge detection identification equipment based on ultrasonic detection method |
| CN112462216A (en) * | 2020-11-30 | 2021-03-09 | 国网山西省电力公司朔州供电公司 | Multi-frequency-band combined type discharge detection system |
| CN112666437A (en) * | 2021-01-29 | 2021-04-16 | 上海杰智电工科技有限公司 | Remote signal acquisition device and partial discharge test system |
-
2011
- 2011-07-12 CN CN2011202449712U patent/CN202119872U/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102998605A (en) * | 2012-12-07 | 2013-03-27 | 山西省电力公司吕梁供电公司 | System and method for signal modulation for panoramic partial discharge monitoring of transformer substation |
| CN103675618A (en) * | 2013-11-30 | 2014-03-26 | 成都科泰地理信息技术有限公司 | Switchgear partial discharge inspecting instrument with printing function |
| CN103969556A (en) * | 2014-03-14 | 2014-08-06 | 上海交通大学 | Insulation electrified detection device for cable accessories |
| CN108919066A (en) * | 2018-05-22 | 2018-11-30 | 广西电网有限责任公司电力科学研究院 | A kind of partial discharge of switchgear detection system and detection method |
| CN111638431A (en) * | 2020-07-14 | 2020-09-08 | 国网山东省电力公司烟台供电公司 | Cubical switchboard partial discharge detection identification equipment based on ultrasonic detection method |
| CN112462216A (en) * | 2020-11-30 | 2021-03-09 | 国网山西省电力公司朔州供电公司 | Multi-frequency-band combined type discharge detection system |
| CN112666437A (en) * | 2021-01-29 | 2021-04-16 | 上海杰智电工科技有限公司 | Remote signal acquisition device and partial discharge test system |
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