CN103412190A - Switch-class device state evaluation method based on parameter on-line identification - Google Patents
Switch-class device state evaluation method based on parameter on-line identification Download PDFInfo
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Abstract
The invention discloses a switch-class device state evaluation method based on impedance parameter on-line identification. The switch-class device state evaluation method is suitable for switch-class devices in the 3/2 connection mode of a transformer substation. Real-time current data of the switch-class devices are used, actual operational data such as line currents and transformer currents inside the transformer substation are combined, resistance distribution conditions of the switch-class devices are identified, therefore, the resistance change conditions of the switch-class devices can be obtained, the abnormal resistance value condition caused by defects of the switch-class devices can be timely discovered, and the important reference basis is provided for device timely defect elimination. According to the switch-class device state evaluation method based on impedance parameter on-line identification, state evaluation on the switch-class devices can be dynamically carried out in an assisting mode, the operation is simple, computing is reliable, the operational cost is much lower than that of site detection testing, and the good adaptability and the good real-time performance are achieved. The switch-class device state evaluation method fills the blank in the field in China and provides a research thought for state maintenance of other high-voltage devices.
Description
Technical field
The present invention relates to Switch equipment on-line parameter identification method, whether have defect in order to online auxiliary diagnosis Switch equipment.Belong to parameters of electric power system identification field.
Background technology
In recent years, the accident of electrical network 500kV isolating switch, disconnector generation catastrophic failure happens occasionally, to equipment, electrical network even personal safety bring larger threat.The contact resistance value of Switch equipment is the important evidence that characterizes its state quality, contact resistance value exceeds normal value and shows that may there be defect in equipment, all may cause contact resistance to increase as the dynamic/static contact problems such as not in place, surface of contact scorification, kinematic link wander off of closing a floodgate.But the factor that affects switch resistance has a lot, because switch resistance is μ Ω level, so the resistance of drainage thread, wire clamp also affects its relative deviation; In addition, due to thermal stability difference, the inconsistent meeting of the size of current flow through makes surface oxidation, and degree of aging is inconsistent, and oxidation and the aging resistance that all can make increase; Electrodynamic effect can affect the fastening degree of the pressure of contact and wire clamp, bolt, thereby affects contact resistance; The pollution level of each phase is inconsistent in addition also can affect resistance sizes.Above factor, when affecting the relative deviation of impedance generation between phase and phase, will cause current imbalance between three-phase.
Because the contact resistance in-site measurement is relatively complicated, in the detection of Switch equipment, can cause the many principles of heating based on the contact resistance increase, often by the means such as Infrared survey judgement defect, but there is following limitation in these class methods:
1, measure and exist periodically, can't real time dynamic tracing equipment state situation.
While 2, carrying out Infrared survey, if it is less to flow through at that time the electric current of equipment under the method for operation, equipment heating is not obvious, may be difficult to the discovering device defect.
3,500kV transformer station adopts 3/2 wiring, due to the shunting action of the equipment such as switch in string, when contact resistance value increases, the shunting of flowing through this switchgear reduces, because heating is directly proportional with current squaring, may cause the fault location heating not obvious, thereby be difficult to find defect.
Utilize the method for operation of power networks data assistant analysis 500kV Switch equipment contact resistance variation situation.Cardinal principle is as follows:
500kV transformer station is general adopts 3/2 wiring, and with 220kV transformer station double bus scheme mode difference commonly used, there is the looped network shunting in 3/2 mode of connection, and when in string during each branch road resistance change, the interior trend that will cause going here and there changes, and now may produce following situation:
1, certain resistance that contacts increases, and causes this phase current with between other two-phase, producing uneven situation, and in the string of this phase, the trend distribution changes simultaneously.
2, the switchgear resistance that respectively contacts all increases, and uneven situation all occurs between each phase current, and in the string of every phase, trend distributes and all changes.
In each string of 500kV transformer station, the resistance value of the equipment such as switch, disconnecting link, guide wire, joint is tens of micro-ohm ranks under normal circumstances, numerical value is small, unavoidably there is a small amount of deviation in each phase resistance value, according to actual operating data, observe, more or less there is uneven situation in each three-phase current, only with current imbalance situation in string, is difficult to locate which platform switchgear contact resistance and increases.But can adopt the mode of parameter identification by existing substation operation data (comprise the shunting of each switch, each go out line current, transformer current), whether resistance value of each string of judgement changes.
Summary of the invention
For overcoming the defect existed in prior art, the invention provides a kind of method for evaluating state of Switch equipment based on on-line parameter identification, can follow the tracks of dynamically in real time Switch equipment contact resistance index, for whether the evaluation Switch equipment defect occurs, provide important reference, help to find in time fault, eliminate defect.
Switch equipment method for evaluating state based on on-line parameter identification is to take following technical scheme to realize, based on the current error minimum principle, the Switch equipment state is carried out to on-line identification, and concrete its step of identification process is as follows:
Measured resistance value while (1) take the putting into operation of Switch equipment in each string of transformer station is initial value, builds the detailed computation model of transformer station;
(2) according to transformer station, go out the actual operating data such as line current, transformer current, according to transformer station's computation model, calculate the current value of each string switch of flowing through;
(3) the Current calculation value of each string switch is compared with actual measured value, obtain current error;
(4) based on the principle of current error minimum, utilize optimized algorithm to change contact resistance value, re-start the switch Calculation of the shunted current, proceed the error ratio pair between same actual measured value, continue to optimize until the error mean square root lower than 4%, Switch equipment contact resistance value now is considered as actual value;
(5) there is the concrete Switch equipment object of defect in the Switch equipment diagnosis changed according to resistance value before and after optimizing.
The aforesaid method for evaluating state of Switch equipment based on on-line parameter identification, it is characterized in that the error minimum principle is for the Switch equipment state evaluation, have advantages of can under any method of operation of system to any transformer station in switchgear carry out parameter identification, have good adaptability and real-time, simultaneously simple to operate, be easy to realize.
Principle of the present invention is specifically described as follows:
(1) first of technical scheme: according to can the arrive at a station contact-ratio model parameter of interior switch of the parameters such as resistance of the equipment actual measurements such as switch, plug-in strip, rheology in station, can build the detailed model of transformer station in conjunction with primary connection figure in electricity grid substation.
(2) second portion of technical scheme: after determining transformer station model and parameter, select the outlet trend of section sometime and transformer trend and busbar voltage as boundary condition, utilize electric system synthesizer PSASP to carry out the simulation calculation of switching current.
(3) third part of technical scheme: in the situation that the actual measurement parameter is not carried out to any check, the Current calculation value of each string switch is compared with actual measured value, obtain current error.
(4) the 4th part of technical scheme: based on the principle of error minimum, utilize optimized algorithm to change contact resistance value, re-start the switch Calculation of the shunted current, proceed the error ratio pair between same actual measured value, continue to optimize until the error minimum, the equipment contact resistance value such as switch now can be considered actual value.
Diagnosis object is interior each Switch equipment of 500kV transformer station string that adopts 3/2 mode of connection.
According to the actual measurement parameter of the resistance of switch, plug-in strip and rheology, carry out the modeling of Switch equipment in transformer station, boundary condition comprises respectively goes here and there in outlet send meritorious and idle, each goes here and there under main transformer self send meritorious and idle, the capacity of the voltage of bus and the interior filter apparatus of string in stand.
Adopt PSASP software diagnosis object to be carried out to the calculating of modeling and switching current.
The described step of utilizing optimized algorithm to change contact resistance value is: by continuous iterative modifications switch resistance value parameter, every iteration is once all calculated once the electric current of each switch, and carry out error ratio pair with the actual measurement electric current, calculate current error, and calculate each switching current mean square of error root, the criterion that iteration finishes is lower than 5% when the switching current error, and in the Optimized Iterative process, switching current error mean square root is compared reduction lower than 10% the time with last round of root mean square, and iterative process finishes.
While building transformer station's computation model, the disconnector of isolating switch and both sides is equivalent to a switchgear.
The resistance order of magnitude of described Switch equipment is all in the micro-ohm level.
The beneficial effect that the present invention reaches:
The present invention is a kind of state of Switch equipment based on impedance parameter on-line identification auxiliary evaluation method.Remote equipment condition diagnosing technology provides technical basis not only for the supervision of status of electric power, can also provide increasing support to maintenance decision, is a kind of aid decision-making method of advanced IT application.Switch equipment state evaluation based on on-line parameter identification can be followed the tracks of Switch equipment contact resistance index in real time dynamically, for whether the evaluation Switch equipment defect occurs, provide important reference, the Switch equipment catastrophic failure occurs for taking precautions against in advance, avoid the personal safety caused, power grid security accident to provide important technology to support, improve electrical network economy and social benefit.This method is generalized to repair based on condition of component by the maintenance of traditional periodic plan, meets the inexorable law of scientific development, helps to find in time the Failure elimination defect, and the safe and stable operation of whole electric system is had important practical significance.This method has proposed the Switch equipment method for evaluating state based on on-line parameter identification, be applicable to the Switch equipment under transformer station's 3/2 mode of connection, according under 3/2 mode of connection, going here and there interior current distributing situation with the closely-related principle of Switch equipment resistance value, utilize the real-time current data of Switch equipment, in conjunction with power transformation Divergent line electric current, the actual operating data such as transformer current, distribution of resistance situation to Switch equipment is carried out identification, thereby obtain the resistance variations situation of Switch equipment, for after Switch equipment generation defect, causing the situation that resistance value is abnormal, can find timely, thereby for the timely defect elimination of equipment provides important reference.The auxiliary state evaluation that carries out switchgear of the method capable of dynamic, calculating simple to operate is reliable, and operating cost is tested far below Site Detection, has good adaptability and real-time.This achievement has made up domestic blank in this field, and also the repair based on condition of component for other high-tension apparatuses provides Research Thinking.
The accompanying drawing explanation
Fig. 1 is station, Wujiang computation model figure;
Station, Fig. 2 Wujiang switching current result of calculation.
Embodiment
The invention will be further described below in conjunction with accompanying drawing.Following examples are only for technical scheme of the present invention more clearly is described, and can not limit the scope of the invention with this.
Take the station, Wujiang is example, and 3/2 mode of connection is adopted at the station, Wujiang, and the equipment contact resistance value such as the interior switch of stand are as shown in table 1, and station, the Wujiang inner model of building as shown in Figure 1.
Equipment contact resistance value (the unit: 10 such as switch in station, table 1 Wujiang
-6Ohm)
Device name in string | Contact resistance (μ Ω) | Device name in string | Contact resistance (μ Ω) |
5003 rheologies | 15 | 5032 plug-in strips | 75 |
5011 switches | 78 | 5032 plug-in strips | 87 |
5011 rheologies | 8 | 5033 switches | 67 |
50111 plug-in strips | 73 | 5033 plug-in strips | 94 |
50112 plug-in strips | 75 | 5041 switches | 76 |
5012 switches | 78 | 5042 switches | 72 |
5012 rheologies | 7 | 5043 switches | 75 |
50121 plug-in strips | 77 | 5051 switches | 76 |
50132 plug-in strips | 81 | 5052 switches | 75 |
5031 switches | 74 | 5052 plug-in strips | 95 |
50312 plug-in strips | 78 | 5053 switches | 73 |
5032 switches | 66 | 5053 plug-in strips | 92 |
In calculating station, gained Wujiang, each switching current as shown in Figure 2.
Station, Wujiang switching current contrast situation is as shown in table 2.
Table 2 is checked the switching current contrast of station, front Wujiang
The switch title | Actual current (A) | Calculate electric current (A) | Absolute deviation (A) | |
5003 | 192.36 | 193.8 | 1.44 | 0.75% |
5011 | 194.34 | 248.3 | 53.96 | 27.77% |
5012 | 7.81 | 52.5 | 44.69 | 572.22% |
5021 | 291.02 | 337.3 | 46.28 | 15.90% |
5022 | 123.05 | 148.2 | 25.15 | 20.44% |
5023 | 214.84 | 176 | -38.84 | -18.08% |
5031 | 113.28 | 139.4 | 26.12 | 23.06% |
5032 | 396.48 | 384.8 | -11.68 | -2.95% |
5033 | 78.12 | 60.8 | -17.32 | -22.17% |
5041 | 210.94 | 237.9 | 26.96 | 12.78% |
5042 | 412.11 | 365.5 | -46.61 | -11.31% |
5043 | 220.7 | 171.4 | -49.3 | -22.34% |
5051 | 185.55 | 205.7 | 20.15 | 10.86% |
5052 | 443.36 | 414.5 | -28.86 | -6.51% |
5053 | 121.09 | 92.6 | -28.49 | -23.53% |
Now station, Wujiang switching current is carried out to error analysis, square error is 148.71%, relative error is very large, paying particular attention to 5012 switching current errors obviously exists unreasonable, have reason to suspect in 5012 stations switchgear exist defect or the field measurement parameter inaccurate, and the upper current imbalance of each string is also more obvious, parameter obviously exists unreasonable, need to carry out by optimized algorithm the iteration of switch resistance, the switching current after continuous compute switch resistance iteration also carries out error ratio pair with the real current error.
After by optimized algorithm, checking, each switch parameter of station, Wujiang, the parameter before and after optimizing is as shown in table 3, finally calculates electric current and actual current and contrasts as shown in table 4.
Station, table 3 Wujiang switch resistance contrasts before and after checking
The switch title | Before check | After check |
5003 | 0.000165 | 0.000165 |
5011 | 0.000234 | 0.000234 |
5012 | 0.000245 | 0.004860 |
5021 | 0.000245 | 0.000249 |
5022 | 0.000245 | 0.000492 |
5023 | 0.000245 | 0.000213 |
5031 | 0.000247 | 0.000289 |
5032 | 0.000238 | 0.000242 |
5033 | 0.000251 | 0.000254 |
5041 | 0.000236 | 0.000270 |
5042 | 0.000232 | 0.000238 |
5043 | 0.000235 | 0.000206 |
5051 | 0.000246 | 0.000246 |
5052 | 0.000260 | 0.000260 |
5053 | 0.000255 | 0.000127 |
From optimum results, after by optimized algorithm, checking, it is mainly that 5012 switch resistances have changed general 20 times that station, Wujiang switch parameter changes.
Table 4 is checked the switching current contrast of station, rear Wujiang
The switch title | Actual current (A) | Calculate electric current (A) | Absolute deviation (A) | |
5003 | 192.36 | 195.8 | 3.44 | 1.79% |
5011 | 194.34 | 203.9 | 9.56 | 4.92% |
5012 | 7.81 | 7.7 | -0.11 | -1.41% |
5021 | 291.02 | 304.1 | 13.08 | 4.49% |
5022 | 123.05 | 117.2 | -5.85 | -4.75% |
5023 | 214.84 | 209.9 | -4.94 | -2.30% |
5031 | 113.28 | 120.1 | 6.82 | 6.02% |
5032 | 396.48 | 408.1 | 11.62 | 2.93% |
5033 | 78.12 | 79 | 0.88 | 1.13% |
5041 | 210.94 | 204 | -6.94 | -3.29% |
5042 | 412.11 | 402.3 | -9.81 | -2.38% |
5043 | 220.7 | 207.8 | -12.9 | -5.85% |
5051 | 185.55 | 182.5 | -3.05 | -1.64% |
5052 | 443.36 | 439.5 | -3.86 | -0.87% |
5053 | 121.09 | 114.9 | -6.19 | -5.11% |
Station, Wujiang switching current after optimizing check is carried out to error analysis, square error is 3.69%, square error now has clear improvement before comparing check, and also balance comparatively of the upper distribution of current of part string, can think that now parameter is very near actual parameter, due to what optimize the front and back Main change, be that 5012 switch resistances have enlarged 20 times, therefore judge that may there be defect in 5012 switches.
In addition, the modeling of this method is that the disconnector of isolating switch and both sides thereof is equivalent to a switchgear, therefore, in the 5012 switch defect reality of determining for this method, may be that one or several in 5012 switches and both sides disconnector go wrong, but this method is for finding that defect provides important evidence, for searching defect, significantly dwindled scope, for in-site measurement, important directive function has been arranged.
The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the technology of the present invention principle; can also make some improvement and distortion, these improvement and distortion also should be considered as protection scope of the present invention.
Claims (7)
1. method for evaluating state of the Switch equipment based on on-line parameter identification is characterized in that: based on the current error minimum principle, the Switch equipment state is carried out to on-line identification, concrete identification process comprises the following steps:
Measured resistance value while (1) take the putting into operation of Switch equipment in each string of transformer station is initial value, builds transformer station's computation model;
(2) according to transformer station, go out line current, transformer current actual operating data, according to transformer station's computation model, calculate the current value of each string switch of flowing through;
(3) the Current calculation value of each string switch is compared with actual measured value, obtain current error;
(4) based on the principle of current error minimum, utilize optimized algorithm to change contact resistance value, re-start the switch Calculation of the shunted current, proceed the error ratio pair between same actual measured value, continue to optimize until the error mean square root lower than 4%, Switch equipment contact resistance value now is considered as actual value;
(5) there is the concrete Switch equipment object of defect in the Switch equipment diagnosis changed according to resistance value before and after optimizing.
2. the method for evaluating state of the Switch equipment based on on-line parameter identification according to claim 1 is characterized in that: diagnosis object is to adopt each Switch equipment in the 500kV transformer station string of 3/2 mode of connection.
3. the method for evaluating state of the Switch equipment based on on-line parameter identification according to claim 1, it is characterized in that: carry out the modeling of Switch equipment in transformer station according to the actual measurement parameter of the resistance of switch, plug-in strip and rheology, boundary condition comprises respectively goes here and there in outlet send meritorious and idle, each goes here and there under main transformer self send meritorious and idle, the capacity of the voltage of bus and the interior filter apparatus of string in stand.
4. the method for evaluating state of the Switch equipment based on on-line parameter identification according to claim 1, is characterized in that: adopt PSASP software diagnosis object to be carried out to the calculating of modeling and switching current.
5. the method for evaluating state of the Switch equipment based on on-line parameter identification according to claim 1, it is characterized in that: the described step of utilizing optimized algorithm to change contact resistance value is: by continuous iterative modifications switch resistance value parameter, every iteration is once all calculated once the electric current of each switch, and carry out error ratio pair with the actual measurement electric current, calculate current error, and calculate each switching current mean square of error root, the criterion that iteration finishes is lower than 5% when the switching current error, and in the Optimized Iterative process, switching current error mean square root is compared reduction lower than 10% the time with last round of root mean square, iterative process finishes.
6. according to claim 1 and the 2 described method for evaluating state of Switch equipment based on on-line parameter identification, it is characterized in that: while building transformer station's computation model, the disconnector of isolating switch and both sides is equivalent to a switchgear.
7. according to claim 1 and the 3 described method for evaluating state of Switch equipment based on on-line parameter identification, it is characterized in that: the resistance order of magnitude of described Switch equipment is all in the micro-ohm level.
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CN104049207A (en) * | 2014-06-27 | 2014-09-17 | 国家电网公司 | Maintenance method for jamming condition of turning on and turning off of disconnecting switch |
CN104268376A (en) * | 2014-09-11 | 2015-01-07 | 国家电网公司 | Online switch resistance assessment method for 3/2 connection mode switching station |
CN104793132A (en) * | 2015-04-21 | 2015-07-22 | 西安工程大学 | Disconnecting switch contact state detection device and method based on electric field sensor |
CN110427152A (en) * | 2019-07-30 | 2019-11-08 | 上海商汤智能科技有限公司 | Assistant teaching method and relevant apparatus |
CN113203917A (en) * | 2021-04-25 | 2021-08-03 | 国网河南省电力公司平顶山供电公司 | Method for pre-judging heating defect of diversion loop of reactive power compensation device |
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CN104049207A (en) * | 2014-06-27 | 2014-09-17 | 国家电网公司 | Maintenance method for jamming condition of turning on and turning off of disconnecting switch |
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CN104268376A (en) * | 2014-09-11 | 2015-01-07 | 国家电网公司 | Online switch resistance assessment method for 3/2 connection mode switching station |
CN104268376B (en) * | 2014-09-11 | 2017-03-15 | 国家电网公司 | A kind of 3/2 mode of connection switchyard switch resistance online evaluation method |
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CN104793132B (en) * | 2015-04-21 | 2018-07-06 | 西安工程大学 | Disconnecting switch contact condition detection device and detection method based on electric-field sensor |
CN110427152A (en) * | 2019-07-30 | 2019-11-08 | 上海商汤智能科技有限公司 | Assistant teaching method and relevant apparatus |
CN110427152B (en) * | 2019-07-30 | 2022-01-28 | 上海商汤智能科技有限公司 | Auxiliary teaching method and related device |
CN113203917A (en) * | 2021-04-25 | 2021-08-03 | 国网河南省电力公司平顶山供电公司 | Method for pre-judging heating defect of diversion loop of reactive power compensation device |
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