The impedance of grounding net of transformer substation frequency sweep and the automatic test diagnosis equipment of amplitude-frequency response
The utility model relates to a kind of transformer station checkout equipment, especially relates to the impedance of a kind of grounding net of transformer substation frequency sweep and the automatic test diagnosis equipment of amplitude-frequency response.
Grounding net of transformer substation is the critical facility guaranteeing electrical equipment and personal safety.Because grounded screen is embedded in underground, often because of soil corrosion for many years, cause grounding body to attenuate and even rupture, make Grounding performance depreciation.At present, engineering is generally judged by power frequency earthing resistance indirectly to the detection of Grounding performance quality, but the corrosion condition of grounded screen cannot be understood.As long as because the grounding body of measured place open circuit does not occur, even if grounded screen is by heavy corrosion, power frequency earthing resistance also can reach regulatory requirements usually.So engineering is all generally after finding that earth mat power frequency earthing resistance is defective or the accident that causes due to ground network defect occurs, search grounded screen breakpoint and corrosion section by dig on a wide area, this method of work is with blindness, and workload is very big.
In addition, it is 50Hz or close to the power-frequency earthing resistance value under 50Hz that at present conventional power frequency earthing resistance tests the impedance ground value obtained, but be in fact short-circuited in transformer station earth fault, or under Lightning Incoming Wave or operation ripple effect, the transient state Transient grounding resistance of grounded screen plays a decisive role.Therefore only measure power-frequency earthing impedance can not represent grounding net of transformer substation can safe operation under fault condition.
Utility model content
The purpose of this utility model be exactly in order to overcome above-mentioned prior art exist defect and the impedance of a kind of grounding net of transformer substation frequency sweep and the automatic test diagnosis equipment of amplitude-frequency response are provided.
The purpose of this utility model can be achieved through the following technical solutions:
A kind of grounding net of transformer substation frequency sweep impedance and the automatic test diagnosis equipment of amplitude-frequency response, is characterized in that, comprises swept-frequency signal and occur, store and signal transmitting apparatus, data collector, observing and controlling analysis and display device and printout module; Described observing and controlling analysis and display device occur with swept-frequency signal respectively, store and signal transmitting apparatus, data collector and printout model calling.
Described swept-frequency signal occurs, storage comprises with signal transmitting apparatus the sweep generator and power amplifier that are connected successively, described sweep generator is connected with observing and controlling analysis and display device, and described power amplifier is connected with data collector.
Described sweep generator is 10-100kHz sweep generator.
Described data collector comprises sampling resistor, Luo-coil and data acquisition unit, described data acquisition unit comprises data acquisition storage and output circuit, communication and control circuit and power-switching circuit, described data acquisition storage is connected with sampling resistor, Luo-coil, communication and control circuit and power-switching circuit respectively with output circuit, described power-switching circuit is connected with communication and control circuit, and described communication and control circuit are connected with power amplifier, observing and controlling analysis and display device respectively.
Described observing and controlling analysis is connected with sweep generator by USB with display device, described observing and controlling analysis is connected with data collector by USB with display device, and described observing and controlling analysis and display device are by TCP/IP network and printout model calling.
Described observing and controlling analysis and display device are notebook computer or industrial computer.
Described printout module is printer.
Compared with prior art, the utility model when not having a power failure and do not excavate earth mat, can understand the running status of grounded screen, judges whether grounded screen corrodes, ensures safety, the reliability service of electric system.And there is the advantages such as the restriction simply, accurately and not being subject to on-the-spot service condition
Accompanying drawing explanation
Fig. 1 is structural representation of the present utility model.
Wherein 1 is sweep generator, and 2 is power amplifier, and 3 is data acquisition unit, and 4 is host computer, and 5 is printer, and 6 is grounded screen, and 7 is down conductor, and 8 is sampling resistor, and 9 is Luo-coil, and 10 is voltage ground pole, a distant place.
Below in conjunction with the drawings and specific embodiments, the utility model is described in detail.
As shown in Figure 1, enter a transformer station, selected this grounding net of transformer substation 61# main transformer earthing bar downlead 7 is swept-frequency signal input end in, according to grounded screen catercorner length according to DL/T475-2006 electric discharge pressure p-wire voltage ground pole 10 afield.Swept-frequency signal input end in and voltage pole p-wire are connected to power amplifier 2.Select wiretap arrester ground row downlead 7 as swept-frequency signal output terminal out.Swept-frequency signal input end in, swept-frequency signal output terminal out are connected to sampling resistor 8, and the Luo-coil that the corresponding down conductor of swept-frequency signal input end in is nested with totally three road voltage signals be connected to data acquisition unit 3.Host computer 4 is connected with sweep generator 1, data acquisition unit 3 by USB interface.The major parameters such as frequency swept signal, frequency interval and amplitude are exported, the sampling rate under the corresponding operating mode of setting data collecting unit 3 by arranging sweep generator 2 in host computer 4.Relevant connection and setting completed, test record also carries out computation and analysis, draws grounded screen frequency sweep impedance curve R (f) and grounded screen 2 selected down conductors amplitude-frequency response H (f) as input and output; Grounded screen running status and extent of corrosion can be assessed with the related coefficient size of history curve H (f) ' according to current frequency sweep impedance variation and current amplitude-frequency response H (f).
The utility model outstanding behaviours business characteristic of the automatic testing and diagnosing of grounding net of transformer substation, utilizes the detection means of electronization to instead of manual detection, enormously simplify means of testing, improve detection efficiency.
In the utility model case study on implementation, sweep generator 1, power amplifier 2, data acquisition unit 3 and host computer 4 all make use of built-in high-capacity direct galvanic battery, also all can utilize ready-made 220V external power source.
The frequency sweep impedance of the utility model grounding net of transformer substation and the automatic test diagnosis equipment host computer 4 of amplitude-frequency response carry out online or off-line carries out computational analysis, generate chart and also export.
System follows open criterion, enjoys maximum data and gather robotization and grounded screen state analysis system under the environment that user is used in reality.In the present system, the opening of system shows the open nature of data acquisition system (DAS), data base management system (DBMS) and applied analysis system, have employed communication standard usb protocol alternately between data.
The foregoing is only specific embodiment of the utility model, but technical characteristic of the present utility model is not limited thereto, any those skilled in the art is again in field of the present utility model, and the change done or modify all is encompassed in the scope of the claims of the present utility model.