CN103472425B - A kind of application process of line selection device for low current performance testing platform - Google Patents
A kind of application process of line selection device for low current performance testing platform Download PDFInfo
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Abstract
The present invention relates to a kind of application process of line selection device for low current performance testing platform, comprising method has: (1) transient fault simulation application: (2) permanent fault simulation application: (3) arcing ground simulation application: (4) high resistance ground simulation application: (5) fault close angle simulation application: (6) each relatively capacitance deviation simulation application: the inconsistent simulation application of (7) zero sequence CT no-load voltage ratio: (8) two CT Parallel test simulation application: (9) loading effects simulation application: (10) PT breaks simulation application: (11) CT breaks simulation application.In labs line selection device for low current performance test and appraisal, can carry out performance test to line selection device for low current according to method proposed by the invention, test respond well, greatly save time cost, measuring accuracy meets the demands comprehensively.
Description
Technical field
The invention belongs to electric system real-timedigital simulation experimental technique field, especially a kind of application process of line selection device for low current performance testing platform.
Background technology
Small Electric Current Earthing And Routing Device both without national standard also without industry standard; national authority detects department when detecting; function and performance are tested by company standard or technical conditions; sundry item such as electromagnetic compatibility, insulating property, mechanical influence, temperature impact etc. are tested by relay protection industry standard and relevant national standard, and cannot carry out dynamic simulation test to this series products.
The factor affecting small current earthing wire-selecting accuracy in running because on-the-spot is a lot, and this series products is without national standard and industry standard, mainly concentrate on Site Detection to the detection method of earthing wire-selecting at present, on-the-spot earth test is the only method that can verifying attachment meet field demand.By on-the-spot earth test, wiring error can be found, zero sequence current mutual inductor precision whether meet the demands and device for the accuracy of this transformer station's route selection, the selection method of this operating mode the most applicable can be adopted if desired, to improve the accuracy rate of route selection for field working conditions.
We have developed a kind of Small Electric Current Earthing And Routing Device performance test and evaluation platform at present, as shown in Figure 1, the real-time simulator (RTDS) that this platform comprises workstation and is connected with workstation Ethernet, real-time simulator (RTDS) is connected with power amplifier, amplify after the current signal of each current transformer (CT) in power amplifier collection real-time simulator (RTDS) and the voltage signal of voltage transformer (VT) (PT), power amplifier is connected with the input of line selection device for low current, electric current after amplification and voltage signal two sub-value are inputed to line selection device for low current, another road input of line selection device for low current is directly connected with the position signalling output terminal of real-time simulator (RTDS), the output of line selection device for low current and performance evaluation model calling, fault distinguishing signal is exported to performance evaluation module, performance evaluation module is connected with the abort situation signal output part of real-time simulator (RTDS) simultaneously, receive the abort situation signal of real-time simulator (RTDS).
As shown in Figure 2, power distribution network equivalent source S1 is provided with in described real-time simulator (RTDS), bus M, be connected by transformer T between bus M with electrical network equivalent source S1, bus M installs voltage transformer pt, the overhead transmission line 4 of bus M drawing the overhead transmission line 1 be made up of isolating switch DL1 series current mutual inductor CT1, the overhead transmission line 2 be made up of isolating switch DL2 series current mutual inductor CT2, the overhead transmission line 3 be made up of isolating switch DL3 series current mutual inductor CT3 side by side and being made up of isolating switch DL4 series current mutual inductor CT4.
At present, above-mentioned Small Electric Current Earthing And Routing Device performance test and the software evaluation method corresponding to evaluation platform a lot, but be not very complete, differ from one another but respectively have deficiency, finding out more preferred method is the direction that these those skilled in the art make great efforts all the time.
Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art, a kind of application process of line selection device for low current performance testing platform is provided.
The present invention solves its technical matters and takes following technical scheme to realize:
An application process for line selection device for low current performance testing platform, comprises method as follows:
(1) transient fault simulation application: in head end, middle-end, the end simulation Single Phase Metal earth fault of each overhead transmission line, cable line, fault is separate is respectively A, B, C phase, and trouble duration is 30ms ~ 200ms;
(2) permanent fault simulation application: simulate single-phase permanent earth fault at the head end of each overhead transmission line, cable line, middle-end, end, fault is separate is respectively A, B, C phase, and trouble duration is greater than 10s;
(3) arcing ground simulation application: simulate single-phase arc-earth faults at the head end of each overhead transmission line, cable line, middle-end, end, fault is separate is respectively A, B, C phase, and trouble duration is 30ms ~ 200ms;
(4) high resistance ground simulation application: single-phase through high resistance earthing fault in the head end of each overhead transmission line, cable line, middle-end, end simulation, fault is separate is respectively A, B, C phase, and trouble duration is 30ms ~ 200ms, and resistance value is 1 ~ 50 Ω;
(5) fault close angle simulation application: in head end, middle-end, the end simulation Single Phase Metal earth fault of each overhead transmission line, cable line, fault close angle is 0 ~ 360 degree, each test increases progressively with 10 degree, observes the performance impact of line selection apparatus under different faults switching angle;
(6) each relatively capacitance deviation simulation application: under simulating each pole line, each separate capacitive unbalance to earth condition of cable line, various earth fault occurs, the degree of deviation is 0 to 30%;
(7) the inconsistent simulation application of zero sequence CT no-load voltage ratio: the zero sequence CT no-load voltage ratio difference simulating each pole line, cable line, the degree of deviation is 0 ~ 10%, simulates various earth fault;
(8) two CT Parallel test simulation application: the current signal that the CT of two pole lines or two cable lines is exported also is accessed line selection apparatus, the various earth fault of line simulation wherein, observes line selection apparatus action situation;
(9) loading effects simulation application: line end is charged resistive load, inductive load and induction-motor load respectively, the various earth fault of analog line, observing different load affects device performance;
(10) PT breaks simulation application: simulation PT broken string or disconnected mutually and various earth fault occurs, checking line selection apparatus voltage starting condition;
(11) CT broken string simulation application: simulation CT broken string or the disconnected various earth fault of tangent generation, observes line selection apparatus action situation.
Advantage of the present invention and good effect are:
(1) the simulation application project of transient fault: consider that in system for distribution network of power, transient fault frequently occurs, and on the sensitivity of line selection apparatus action and accuracy impact very serious, design in the present invention this application item can dummycable, there is transient fault in optional position on pole line, reaches the object verifying various principle line selection apparatus route selection function accuracy.
(2) permanent fault simulation application: the line selection apparatus of some principle will could obtain good route selection effect through sufficiently long fault-time, like this when trouble duration is shorter occur as instantaneity short trouble time, its route selection effect will be greatly affected, so trouble duration is also the important indicator affecting route selection accuracy.Design this application item in the present invention and can regulate trouble duration arbitrarily, to distinguish different principle route selection rapidity and accuracy.
(3) arcing ground simulation application: the cable line in distribution system, the route selection function effect of the intermittent ground connection of arc light to the line selection apparatus of some principles caused because of insulation breakdown is the most serious.Design this application item in the present invention to regulate arbitrarily the fault quiescent interval and produce the moment, to verify whether the line selection apparatus route selection function of various principle can not affect by ground connection degree of stability.
(4) high resistance ground simulation application: because strong wind, construction such as to touch at the uncertain factor by mistake; overhead transmission line in distribution system can occur often through high resistance ground; the monitor signal of some route selection functions is very responsive to the size of stake resistance resistance; the stake resistance acquired a certain degree can cut down monitor signal, thus affects route selection function.Designing this application item in the present invention can the size of regulated ground resistance arbitrarily, to verify various principle line selection apparatus route selection function whether by the impact of stake resistance size.
(5) fault close angle simulation application: if break down in the phase voltage crest moment, namely switching angle is 90 °, the zero-sequence current value obtained in circuit is larger, favourable to some selection methods; But when switching angle is less of the fault that is short-circuited when 0 °, the signal amplitude that part selection method utilizes will be very little, thus route selection effect is greatly affected.Design this application item in the present invention and can fault trigger instants be set arbitrarily, to verify whether various principle line selection apparatus route selection function is subject to the impact of switching angle.
(6) each relatively capacitance deviation simulation application: in distribution system circuit triphase parameter imbalance cause each relatively capacitance deviation is inconsistent, during the fault that is short-circuited, capacitance current distribution is uneven, causes malfunction or the tripping of some route selection functions.Designing this application item in the present invention can each relatively capacitance deviation degree arbitrarily, to verify various principle line selection apparatus route selection function whether by the impact of capacitance deviation size.
(7) the inconsistent simulation application of zero sequence CT no-load voltage ratio: because of the reason such as lectotype selection, construction, there is error in the zero sequence CT no-load voltage ratio used in distribution system.Design this application item in the present invention, under being intended to checking TA no-load voltage ratio disunity or the skimble-scamble situation of polarity, can route selection product realize accurate route selection by other means (software compensation etc.).
(8) two CT Parallel test simulation application: design this application item in the present invention, two sections of buses of simulation parallel running, there is singlephase earth fault in its median generatrix one, bus two does not break down, if now route selection product judges that bus two is as non-fault or busbar grounding fault, then this route selection action is correct.
(9) loading effects simulation application: in distribution system, load is of a great variety, as appliance load, commercial load, industrial load etc., the impact of high capacity motor frequent start-stop to system in industrial load is huge, also very serious on the impact of line selection apparatus.Design this application item in the present invention, the combination of analog line end difference charged resistive load, inductive load, induction-motor load or various load, and the various earth fault of analog line, checking different load affects device performance.
(10) PT breaks simulation application: simulation PT broken string or disconnected mutually and various earth fault occurs, checking line selection apparatus voltage starting condition;
(11) CT broken string simulation application: simulation CT broken string or the disconnected various earth fault of tangent generation, observes line selection apparatus action situation.
Accompanying drawing explanation
Fig. 1 is line selection device for low current performance testing platform wiring schematic diagram;
Wiring schematic diagram when Fig. 2 is line selection device for low current performance testing platform in emulator (RTDS).
Embodiment
Below in conjunction with accompanying drawing, the embodiment of the present invention is further described, it is emphasized that following embodiment is illustrative, instead of determinate, can not in this embodiment as limitation of the invention.
A kind of Small Electric Current Earthing And Routing Device performance testing platform, as shown in Figure 1, the real-time simulator (RTDS) that this platform comprises workstation and is connected with workstation Ethernet, real-time simulator (RTDS) is connected with power amplifier, amplify after the current signal of each current transformer (CT) in power amplifier collection real-time simulator (RTDS) and the voltage signal of voltage transformer (VT) (PT), power amplifier is connected with the input of line selection device for low current, electric current after amplification and voltage signal two sub-value are inputed to line selection device for low current, another road input of line selection device for low current is directly connected with the position signalling output terminal of real-time simulator (RTDS), the output of line selection device for low current and performance evaluation model calling, fault distinguishing signal is exported to performance evaluation module, performance evaluation module is connected with the abort situation signal output part of real-time simulator (RTDS) simultaneously, receive the abort situation signal of real-time simulator (RTDS).
As shown in Figure 2, power distribution network equivalent source S1 is provided with in described real-time simulator (RTDS), bus M, be connected by transformer T between bus M with electrical network equivalent source S1, bus M installs voltage transformer pt, the overhead transmission line 4 of bus M drawing the overhead transmission line 1 be made up of isolating switch DL1 series current mutual inductor CT1, the overhead transmission line 2 be made up of isolating switch DL2 series current mutual inductor CT2, the overhead transmission line 3 be made up of isolating switch DL3 series current mutual inductor CT3 side by side and being made up of isolating switch DL4 series current mutual inductor CT4.
Innovative point of the present invention is:
An application process for line selection device for low current performance testing platform, comprises method as follows:
(1) transient fault simulation application: in head end, middle-end, the end simulation Single Phase Metal earth fault of each overhead transmission line, cable line, fault is separate is respectively A, B, C phase, and trouble duration is 30ms ~ 200ms;
(2) permanent fault simulation application: simulate single-phase permanent earth fault at the head end of each overhead transmission line, cable line, middle-end, end, fault is separate is respectively A, B, C phase, and trouble duration is greater than 10s;
(3) arcing ground simulation application: simulate single-phase arc-earth faults at the head end of each overhead transmission line, cable line, middle-end, end, fault is separate is respectively A, B, C phase, and trouble duration is 30ms ~ 200ms;
(4) high resistance ground simulation application: single-phase through high resistance earthing fault in the head end of each overhead transmission line, cable line, middle-end, end simulation, fault is separate is respectively A, B, C phase, and trouble duration is 30ms ~ 200ms, and resistance value is 1 ~ 50 Ω;
(5) fault close angle simulation application: in head end, middle-end, the end simulation Single Phase Metal earth fault of each overhead transmission line, cable line, fault close angle is 0 ~ 360 degree, each test increases progressively with 10 degree, observes the performance impact of line selection apparatus under different faults switching angle;
(6) each relatively capacitance deviation simulation application: under simulating each pole line, each separate capacitive unbalance to earth condition of cable line, various earth fault occurs, the degree of deviation is 0 to 30%;
(7) the inconsistent simulation application of zero sequence CT no-load voltage ratio: the zero sequence CT no-load voltage ratio difference simulating each pole line, cable line, the degree of deviation is 0 ~ 10%, simulates various earth fault;
(8) two CT Parallel test simulation application: the current signal that the CT of two pole lines or two cable lines is exported also is accessed line selection apparatus, the various earth fault of line simulation wherein, observes line selection apparatus action situation;
(9) loading effects simulation application: line end is charged resistive load, inductive load and induction-motor load respectively, the various earth fault of analog line, observing different load affects device performance;
(10) PT breaks simulation application: simulation PT broken string or disconnected mutually and various earth fault occurs, checking line selection apparatus voltage starting condition;
(11) CT broken string simulation application: simulation CT broken string or the disconnected various earth fault of tangent generation, observes line selection apparatus action situation.
Claims (1)
1. an application process for line selection device for low current performance testing platform, is characterized in that comprising method as follows:
(1) transient fault simulation application: all carry out the separate simulation Single Phase Metal earth fault being respectively A, B, C phase of fault at the head end of each overhead transmission line, cable line, middle-end, end, trouble duration is 30ms ~ 200ms;
(2) permanent fault simulation application: all carry out the separate single-phase permanent earth fault of simulation being respectively A, B, C phase of fault at the head end of each overhead transmission line, cable line, middle-end, end, trouble duration is greater than 10s;
(3) arcing ground simulation application: all carry out the separate single-phase arc-earth faults of simulation being respectively A, B, C phase of fault at the head end of each overhead transmission line, cable line, middle-end, end, trouble duration is 30ms ~ 200ms;
(4) high resistance ground simulation application: all carry out the separate simulation being respectively A, B, C phase of fault at the head end of each overhead transmission line, cable line, middle-end, end single-phase through high resistance earthing fault, trouble duration is 30ms ~ 200ms, and resistance value is 1 ~ 50 Ω;
(5) fault close angle simulation application: all carry out the simulation Single Phase Metal earth fault that fault close angle is 0 ~ 360 degree at the head end of each overhead transmission line, cable line, middle-end, end, each test increases progressively with 10 degree, observes the performance impact of line selection apparatus under different faults switching angle;
(6) each relatively capacitance deviation simulation application: under simulating each pole line, each separate capacitive unbalance to earth condition of cable line, various earth fault occurs, the degree of deviation is 0 to 30%;
(7) the inconsistent simulation application of zero sequence CT no-load voltage ratio: the zero sequence CT no-load voltage ratio difference simulating each pole line, cable line, the degree of deviation is 0 ~ 10%, simulates various earth fault;
(8) two CT Parallel test simulation application: the current signal that the CT of two pole lines or two cable lines is exported also is accessed line selection apparatus, the various earth fault of line simulation wherein, observes line selection apparatus action situation;
(9) loading effects simulation application: line end is charged resistive load, inductive load and induction-motor load respectively, the various earth fault of analog line, observing different load affects device performance;
(10) PT breaks simulation application: simulation PT broken string or disconnected mutually and various earth fault occurs, checking line selection apparatus voltage starting condition;
(11) CT broken string simulation application: simulation CT broken string or the disconnected various earth fault of tangent generation, observes line selection apparatus action situation.
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| CN105445616B (en) * | 2015-11-16 | 2018-08-07 | 西安交通大学 | A kind of Little Current Ground Connection System and method based on controlled zero-sequence current |
| CN105403810B (en) * | 2015-12-03 | 2018-09-07 | 国网山东省电力公司电力科学研究院 | A kind of fault line selection for indirectly grounding power system device universal test system and method |
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| CN106199300A (en) * | 2016-06-21 | 2016-12-07 | 国网河南省电力公司漯河供电公司 | A kind of method of testing of low current neutral grounding system fault route selecting device |
| CN107462801A (en) * | 2017-08-14 | 2017-12-12 | 国网天津市电力公司 | A kind of portable Small Electric Current Earthing And Routing Device dynamic simulation test device |
| CN109283437A (en) * | 2018-11-06 | 2019-01-29 | 国网四川省电力公司技能培训中心 | PT broken string and singlephase earth fault simulator and method |
| CN111983385A (en) * | 2020-08-19 | 2020-11-24 | 国网河南省电力公司漯河供电公司 | Line fault testing method based on asymmetry |
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