Background technology
In electric system, moving power equipments such as a large amount of generators, transformer, high-voltage switch gear, voltage transformer (VT), current transformer, bushing, coupling condenser, insulator, these equipment withstand long term exposure that is in operation high-tension effect, the quality of their state of insulations directly affects the safe operation of electrical network.In case these electrical equipment insulation damages cause equipment breakdown, except causing direct economic loss, also can cause large-area power-cuts, indirect loss is huge.In order to monitor the insulation status of power equipment, guarantee the safety of power equipment, power department has been worked out a series of testing regulations, as electrical equipment handing-over and preventive trial rules, by regular preventive trial, monitor the insulation status of electrical equipment, find the defective of electrical equipment, lack processing so that disappear, ensure the safe operation of electrical network.
But along with improving constantly of line voltage grade, the continuous increase of power system capacity has brought series of new problems also for the Insulation Test of high voltage electric equipment, and people have recognized that gradually there are many weak points in traditional preventive trial method:
When 1, going preventive trial, tested electrical equipment needs to have a power failure, and will influence the power supply to the user;
When 2, preventing the property test, the state of tested device and operating state are inconsistent, and (trial voltage of 110kV grade and above electrical equipment preventive test is low, is 10kV as the dielectric loss trial voltage, the situation in the time of can not representing actual motion;
3, because the preventive trial cycle is long, the preventive trial cycle that regularly has a power failure is 1 year to 3 years, and operating equipment also often breaks down during intertrial interval;
4, excessive to the power failure of electrical equipment, even, cause waste even possibility damage equipment because status of equipment well still need have a power failure by the cycle of fixing to be tested and maintenance.
Because above various reasons, impel people extensively to carry out insulated on-line monitoring Study on Technology under the service condition, compare with traditional regular power failure preventive trial, on-line monitoring has series of advantages: can improve the authenticity and the sensitivity of electrical equipment test greatly, because the state during test is exactly an equipment running status; Needn't arrange prerun power failure plan, this has brought convenience obviously for the operation of electric system; Can select the different test periods according to the insulation status of equipment, the validity of test obviously be improved, and can realize real-time monitoring.
The insulation of electrical installation on-line monitoring will become an important component part of preventive trial, it will be in many aspects the Mi deficiency of mending regular power failure preventive trial.For example, infrared measurement of temperature, dissolved gas analysis, the introducing of on-line monitoring projects such as lightning arrester, quite effective to finding some defective.The applying to also help of on-line monitoring carries out the transition to more rational state maintenance with electrical equipment from periodic maintenance.China relevant departments are also working out electrical equipment state maintenance guide rule.
The basis of state maintenance just is insulated on-line monitoring and diagnostic techniques, correctly diagnose the operation conditions of tested electrical equipment by various monitoring meanss, waits to determine that according to itself characteristic and variation tendency can this equipment continue operation or its time between overhauls(TBO).
China is in just the begin one's study method of insulated on-line monitoring of the eighties.It is whole nation unit the earliest that Anhui Academy of Electric Power Sciences carries out the insulated on-line monitoring technical research.Develop first insulation line monitoring device of China, and be installed in the quarrying electric substation of Ma'an Mountain electric company of our province.Subsequently, Anhui Academy of Electric Power Sciences also develops the insulation line monitoring device of multiple different model in succession.The whole nation is high voltage electric equipment insulated on-line monitoring technical seminar view for the first time, holds in the Maanshan City of our province, and meeting has affirmed that insulated on-line monitoring is a developing direction from now on.Enter the nineties, each universities and colleges of the whole nation and electric power research department have all carried out insulated on-line monitoring Study on Technology under the service condition on a large scale, developed a series of new product: concentrate insulated on-line monitoring system as WYJ-III type microcomputer that flourish company of Ma'an Mountain Wanyuan Electric Applicance Co., Ltd and sky, Fuyang produces, the centralized insulated on-line monitoring system of GD-8 microcomputer of the electric limited production of the high moral in Wuhan, DZJ-IV insulated on-line monitoring system, Tsing-Hua University in addition that University Of Chongqing produces, more than 20 tame R﹠D institutions such as Xi'an Communications University have all developed the insulated on-line monitoring system of different types.Nearly 200 cover insulated on-line monitoring systems have been installed by 1988-2005 generating plant, a tree name incomplete statistics whole nation and electric company.
The insulated on-line monitoring system structure of China's development and production is divided into three kinds of forms at present: centralized; Concentrate distributed; Portable.The signal transmission is divided into two kinds: digital data transmission; Analog signal transmission.The sample of signal sensor is divided into three kinds: resistance sampling; Capacitor sampling; The sampling of core-theaded type current transformer.
Because insulated on-line monitoring system lacks necessary technology test and verification means both at home and abroad, all insulated on-line monitoring systems all do not carry out regular factory inspection and on-the-spot commissioning test, be in operation and also can't carry out periodic check to performance condition, accuracy of test and the sensitivity of Insulation Live Testing system, the accuracy of the data that insulated on-line monitoring system monitors and validity are subjected to carrying out the evaluation of science.So insulated on-line monitoring temporarily also can't replace the preventive trial that regularly has a power failure.Falsehood appears in the data that the insulated on-line monitoring system that has monitors, thereby has withdrawed from operation, has caused great waste.Therefore, the variation of insulated on-line monitoring data temporarily can't be as the foundation of judging high voltage equipment insulation situation in service.Also perplexing the development of insulated on-line monitoring technology for many years, be the insoluble technical barrier in home and abroad always.
Summary of the invention
The objective of the invention is: a kind of insulated on-line monitoring system checker of high-voltage electric equipment that the monitoring sensitivity, Monitoring Data accuracy and the reliability that are installed in on-the-spot high voltage electric equipment insulated on-line monitoring system are carried out verification and evaluation that solves is provided.
Concrete technical solution is such:
1, insulated on-line monitoring system checker of high-voltage electric equipment is characterized in that: comprise power circuit, reference fluid loss and standard current generator circuit and Zinc-Oxide Arrester total current and current in resistance property generator circuit;
Described power circuit comprises contact type voltage regulator B1, BCI type spiral arm line formula resistor B2 and standard potential transformer B3, the input termination 220V power supply of contact type voltage regulator B1, export termination BCI type spiral arm line formula resistor B2 and standard potential transformer B3 once, standard potential transformer B3 secondary output termination standard losses generator circuit; Standard potential transformer B3 secondary output terminal also and connect the measuring voltage table, output end voltage is 57.7V;
Described reference fluid loss and standard current generator circuit comprise 3 standard capacitance CN1 in parallel, CN2, CN3,18 resistance and 3 K switch 1, K2, K3; Connect the power circuit input end after the end parallel connection of 3 standard capacitance CN1 in parallel, CN2, CN3, the other end of 3 standard capacitance CN1 in parallel, CN2, CN3 connects an end of 6 resistance respectively; 6 resistance that connect standard capacitance CN1 are R1, R2, R3, R4, R5 and R6, and the other end of 6 resistance connects 6 contacts of K switch 1 respectively; 6 resistance that connect standard capacitance CN2 are R7, R8, R9, R10, R11 and R12, and the other end of 6 resistance connects 6 contacts of K switch 2 respectively; 6 resistance that connect standard capacitance CN3 are R13, R14, R15, R16, R17 and R18, and the other end of 6 resistance connects 6 contacts of K switch 3 respectively; Connect the A point of standard output terminal after the other end parallel connection of K switch 1, K2, K3, the B point ground connection of standard output terminal;
After 3 resistance R 19 of described Zinc-Oxide Arrester total current and current in resistance property generator circuit, R20, R21 and capacitor C 4 were in parallel, the series current table connect total current and current in resistance property output terminal H point again, corresponding total current and current in resistance property output terminal G point ground connection; The other end of resistance R 19, R20, R21 connects three contacts of K switch 4 respectively, and the other end of capacitor C 4 connects the other end of K switch 4, and K switch 5 is connected with K switch 4, K switch 5 another termination powers.
2, according to above-mentioned insulated on-line monitoring system checker of high-voltage electric equipment, it is characterized in that: capacitor C N1, the CN2 in described reference fluid loss and the standard current generator circuit, the capacity of CN3 are respectively 0.15~0.25 μ F; 0.38~0.42 μ F; 0.76~0.84 μ F; The resistance of resistance R 1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18 is respectively 12.7~21.2 Ω; 25.4~42.4 Ω; 50.8~84.9 Ω; 63.5~106 Ω; 101.6~169.6 Ω; 127~212 Ω; 7.58~8.38 Ω; 15.16~16.76 Ω; 30.32~33.52 Ω; 37.9~41.9 Ω; 60.64~67.04 Ω; 75.8~83.8 Ω; 3.79~4.19 Ω; 7.58~8.38 Ω; 15.16~16.76 Ω; 18.95~20.95 Ω; 30.32~33.52 Ω; 37.9~41.9 Ω.
3, according to above-mentioned insulated on-line monitoring system checker of high-voltage electric equipment, it is characterized in that: the capacitor C 4 in described Zinc-Oxide Arrester total current and the current in resistance property generator circuit is 0.5225~0.5775 μ F;
The resistance of resistance R 19, R20, R21 is respectively 56.943~57.057k Ω; 113.886~114.114k Ω; 288.2115~288.7885k Ω.
Dielectric loss tg δ, electric capacity C, electric current I and the total current I of this checker verification simultaneously high voltage electric equipment insulated on-line monitoring system
0With current in resistance property I
RThis checker can carry out field-checking and laboratory verification to the high voltage electric equipment insulated on-line monitoring system of arbitrary form.
Useful technique effect of the present invention is embodied in several aspects:
1, the present invention adopts 57.7V low pressure check system, under the prerequisite of guaranteeing the person and device security, has also guaranteed testing accuracy.
2, checker of the present invention can be checked the insulated on-line monitoring system of multiple different model.Select the 110kV of insulated on-line monitoring system of arbitrary operation or 220kV and 500kV current transformer, capacitance type potential transformer, lightning arrester, main transformer sleeve pipe, coupling condenser uniformly-spaced to test, standard output terminal, the zinc paste that the input end that is verified the current sampling sensor of equipment is connected to the standard losses generator of this tester is warded off the output terminal of thunder device total current and current in resistance property generator, simultaneously, the normal voltage output terminal that the input end that is verified the voltage sampling sensor of equipment is connected to this tester can be tested.
3, this checker is successfully to centralized, concentrate distributed, portable, signal is transmitted as digital data transmission and analog signal transmission, and the sample of signal sensor is that the Insulation Live Testing system of resistance sampling, capacitor sampling and the sampling of core-theaded type current transformer has carried out scene and laboratory verification.Obtained satisfied result.To realize the verification of insulated on-line monitoring system cycle, the accuracy of insulated on-line monitoring data is subjected to people's approval, and will progressively replace power failure preventive trial data.
4, this checker reflected the performance present situation of insulated on-line monitoring system really at X-ray inspection X, and need not high voltage electric equipment is had a power failure, the method for inspection is simple, reliable, economic benefit and work efficiency significantly improve.
5, regularly the Insulation Live Testing system is carried out verification by checker, guarantee the reliability of insulated on-line monitoring system Monitoring Data, in time reflect the operational outfit insulation status, for the repair based on condition of component of progressively realizing power equipment provides technical support.
Embodiment
Below in conjunction with accompanying drawing, the present invention is further described by embodiment.
Embodiment 1:
Insulated on-line monitoring system checker of high-voltage electric equipment comprises power circuit, reference fluid loss and standard current generator circuit and Zinc-Oxide Arrester total current and current in resistance property generator circuit, sees Fig. 1.
Power circuit comprises contact automatic coupling voltage regulator B1, BCI type spiral arm line formula resistor B2 and standard potential transformer B3, the input termination 220V power supply of contact type voltage regulator B1, output termination slide wire resistance B2; The input end of standard potential transformer B3 connects slide wire resistance B2, output termination standard losses generator circuit; Output terminal shunt voltage table, output end voltage are 57.7V;
Contact automatic coupling voltage regulator B1; Model: TDGC-0.5; Rated capacity: 0.5kV; Single-phase: 50Hz; Output voltage: 0~100V; Maximum current: 2A.
BCI type spiral arm line formula resistor B2 is to fix with the high-temperature glaze sintering after adopting alloy resistance wire to be around on the annular ceramic skeleton, and the disk center is equipped with rotating shaft and drives brush on resistive element, thereby obtains the resistance value of variation.Advantages such as the BCI rheostat has that power is big, humidity, range of adjustment are big.Be applicable to usefulness such as low-frequency ac do adjusting control voltage, electric current or adjustable pull-up resistor.B2 resistor range of adjustment is: 0~100 Ω.Power is: 50W.
The concrete parameter of standard potential transformer B3 is as follows:
Rated primary voltage: 100V
Rated secondary voltage standard value: 57.7V
The power-factor of load: 1
Rated frequency: 50Hz
Industrial frequency withstand voltage intensity: a winding is to the industrial frequency experiment voltage between Secondary Winding and the ground terminal〉2kV
Class of accuracy: 0.1 grade.
The lifting variation: voltage up-down differs from 0.04% (when following rated primary voltage percentage);
The phase place lifting differs from 2 ' and (when following rated primary voltage percentage);
Reliability requirement: the mean time between failures of mutual inductor (mtbf) must not be less than 10000h.
Reference fluid loss and standard current generator circuit comprise 3 standard capacitance CN1 in parallel, CN2, CN3,18 resistance and 3 K switch 1, K2, K3; Connect the power circuit input end after the end parallel connection of 3 standard capacitance CN1 in parallel, CN2, CN3, the other end of 3 standard capacitance CN1 in parallel, CN2, CN3 connects an end of 6 resistance respectively; 6 resistance that connect standard capacitance CN1 are R1, R2, R3, R4, R5 and R6, and the other end of 6 resistance connects 6 contacts of K switch 1 respectively; 6 resistance that connect standard capacitance CN2 are R7, R8, R9, R10, R11 and R12, and the other end of 6 resistance connects 6 contacts of K switch 2 respectively; 6 resistance that connect standard capacitance CN3 are R13, R14, R15, R16, R17 and R18, and the other end of 6 resistance connects 6 contacts of K switch 3 respectively; Connect the A point of standard output terminal after the other end parallel connection of K switch 1, K2, K3, the B point ground connection of standard output terminal;
After 3 resistance R 19 of Zinc-Oxide Arrester total current and current in resistance property generator circuit, R20, R21 and capacitor C 4 were in parallel, the series current table connect total current and current in resistance property output terminal H point again, corresponding current in resistance property output terminal G point ground connection; The other end of resistance R 19, R20, R21 connects three contacts of K switch 4 respectively, and the other end of capacitor C 4 connects the other end of K switch 4, and K switch 5 is connected with K switch 4, and K switch 5 another termination powers are seen Fig. 2.
Checker technical indicator of the present invention is as follows:
(1), reference fluid loss tg output:
Scope: 0.1%; 0.2%; 0.4%; 0.5%; 0.8%; 1.0%;
Reference fluid loss tg error: ± 0.1%.
(2), electric capacity output:
Scope: 0.2 μ F; 0.4 μ F; 0.8 μ F;
Error: ± 0.1%.
(3), normalized current In output:
Scope: 3.6mA; 7.2mA; 14.4mA;
Error: ± 0.1%.
(4), total current output: 10mA; Error: ± 0.1%.
(5), current in resistance property output:
Scope: 200 μ A; 500 μ A; 1000 μ A;
Error: ± 0.5%.
The standard losses generator selects 1 (0.1% by loss; 0.2%; 0.4%; 0.5%; 0.8%; 1.0%), loss selects 2 (0.1%; 0.2%; 0.4%; 0.5%; 0.8%; 1.0%), loss selects 3 (0.1%; 0.2%; 0.4%; 0.5%; 0.8%; 1.0%) constitutes.And generation reference fluid loss tg δ.CN1, CN2, CN3 are lossless standard electric capacity, R
1~R
18Be the standard noninductive resistance.
The standard losses generator is the core of insulated on-line monitoring system checker of high-voltage electric equipment, and reference fluid loss tg δ accuracy depends on standard capacitor C
NPrecision and stability with measuring resistance R.
If the C in the circuit
NDielectric loss tg δ
n≈ 0; C
N=0.2 μ F; Tg δ
Whole=0.1%.
Tg δ
Whole≈ tg δ
n+ ω C
NR;=ω C
NR;
Calculate 0.2% according to above formula; 0.4%; 0.5%; 0.8%; 1.0% resistance value; That is:
The resistance of resistance R 1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18 is respectively 15.92 Ω, 31.84 Ω, 63.68 Ω, 79.6 Ω, 127.4 Ω, 159.2 Ω, 7.962 Ω, 15.92 Ω, 31.85 Ω, 39.81 Ω, 63.69 Ω, 79.62 Ω, 3.98 Ω, 7.96 Ω, 15.92 Ω, 19.91 Ω, 31.84 Ω, 39.81 Ω.
Capacitor C N1, CN2 in the consumption device circuit decrease to take place in standard, the capacity of CN3 is respectively: 0.2 μ F,, 0.4 μ F, 0.8 μ F.
Standard losses generation generator has two functions, both: produce reference fluid loss tg δ and normalized current I
N
According to circuit parameter C
N=0.2 μ F; R=159.2 Ω (selecting 1 maximum value); U
N=57.7V.Calculate normalized current I
NValue:
In the formula:
Be standard capacitor C
NCapacitive reactance promptly:
Can go out (selecting 2) and (selecting 3) normalized current I according to above computing method
N
Capacitor C 4 in Zinc-Oxide Arrester total current and the current in resistance property generator circuit is 0.55 μ F;
The resistance of resistance R 19, R20, R21 is respectively 57k Ω; 114k Ω; 288.5k Ω.
Zinc-Oxide Arrester total current and current in resistance property generator circuit produce total current I
0With current in resistance property I
R, the total current I of generation
0Be 10mA; Current in resistance property I
RNBe respectively 200 μ A; 500 μ A; 1000 μ A.
The total current generator
The K5 normal voltage that closes a switch U
NBe added in circuit C
N4Go up the formation path with sample resistance r and produce total current I
0, total current I
0Deliver to the insulated on-line monitoring system that is verified by lead-out terminal.In the circuit because sample resistance r<<Z
C4, Z
C4Capacitive reactance for standard capacitor.
Ignored current sampling resistor r when calculating in the circuit; That is:
The current in resistance property generator
The K5 that the closes a switch current in resistance property selector switch K4 that closes again pushes 1000 μ A shelves, normal voltage U as selector switch K4
NBe added in C
N4And R
19Series connection forms path with sample resistance r again on the circuit after the parallel connection, produces the electric current I that contains resistive component
R, deliver to the insulated on-line monitoring system that is verified by lead-out terminal.
The checker principle of work
(1), before the power turn-on K switch, the output no-voltage of voltage regulation loop B1, B2 and standard potential transformer B3, voltage table V are designated as zero.Select K1, K2, K3 all to be allocated to zero-bit.Current in resistance property selects K4 to be allocated to the position of pass, and Zinc-Oxide Arrester measuring switch K5 is allocated to the position of pass, and reometer A is designated as zero.
A, will be connected on the normalized current lead-out terminal " A " of checker by the current sampling sensor signal end of the insulated on-line monitoring system of verification.
B, will be connected to the normal voltage lead-out terminal " U of checker by the reference voltage sampling detector signal end of the insulated on-line monitoring system of verification
N" on.
(2), at first with ground terminal GND dead earthing, power turn-on K switch 1, regulate contact type voltage regulator coarse adjustment knob B1 and slide wire resistance fine tuning knob B2 and make voltage table V indication 57.7V, then according to being selected K1 (3.6mA), K2 (7.2mA), K3 (14.4mA) by the size of the insulated on-line monitoring system current sampling sensor input current of verification.
A, as having selected K1 (3.5mA), with K1 by " 0 " position push " 1 " position at this moment checker be output as:
1., reference fluid loss tg δ is 0.1%;
2., the standard electric capacity is 0.2 μ F;
3., normalized current is 3.6mA.
After b, dielectric loss tg δ, electric capacity C, electric current I verification finish, K1 dialled by " 1 " position get back to " 0 " position.
C, before the K5 that closes a switch, will be connected on the lead-out terminal " H " of checker by the Zinc-Oxide Arrester current sampling sensor signal end of the insulated on-line monitoring system of verification.According to by the size of the insulated on-line monitoring system Zinc-Oxide Arrester current sampling sensor input current of verification, selective oxidation zinc lightning arrester is measured the position of selector switch position K4 then.At this moment checker is output as:
1., total current is: 10mA;
2., current in resistance property: " 1 " is 200 μ A; " 2 " are 500 μ A; " 3 " are 1000 μ A.
This insulated on-line monitoring system checker of high-voltage electric equipment can carry out verification easily to it to being provided multinomial standard volume by the insulated on-line monitoring system of verification,
(3), this checker adopts low pressure (57.7V) check system, under the prerequisite of guaranteeing the person and device security, also guaranteed checking precision.The core of this checker is the standard losses generator, and the standard losses numerical value (0.1%~1.0%) that is produced by the standard losses generator is transferred to insulated on-line monitoring system, and insulated on-line monitoring system demonstrates standard figures (as: 0.1%~1.0%).This checker can experimentize with the insulated on-line monitoring system of multiple different model chamber and field-checking.
(4), this checker can be checked any one insulated on-line monitoring system.Select 110kV, 220kV and 500kV current transformer, capacitance type potential transformer, lightning arrester, main transformer sleeve pipe, the coupling condenser of the on-line monitoring system of arbitrary operation uniformly-spaced to test, the input end (current transformer end screen downlead need disconnect) that is verified the current sampling sensor of equipment WYJ-III type or other model on-line monitoring systems is connected to the I of this checker
NOn the terminal, and with the normal voltage voltage of this checker output U
NTerminal is connected to the input end of the voltage sampling sensor of the centralized on-line monitoring system of WYJ-III type microcomputer, and PT secondary sample voltage originally should disconnect, the test of can testing.
Embodiment 2:
Capacitor C N1, CN2 in reference fluid loss and the standard current generator circuit, the capacity of CN3 are respectively 0.15 μ F; 0.38 μ F; 0.76 μ F;
The resistance of resistance R 1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18 is respectively 12.7 Ω; 25.4 Ω; 50.8 Ω; 63.5 Ω; 101.6 Ω; 127 Ω; 7.58 Ω; 15.16 Ω; 30.32 Ω; 37.9 Ω; 60.64 Ω; 75.8 Ω; 3.79 Ω; 7.58 Ω; 15.16 Ω; 18.95 Ω; 30.32 Ω; 37.9 Ω;
Capacitor C 4 in Zinc-Oxide Arrester total current and the current in resistance property generator circuit is 0.5225; The resistance of resistance R 19, R20, R21 is respectively 56.943k Ω; 113.886k Ω; 288.2115k Ω;
Other is with embodiment 1.
Embodiment 3:
Capacitor C N1, CN2 in reference fluid loss and the standard current generator circuit, the capacity of CN3 are respectively 0.25 μ F; 0.42 μ F; 0.84 μ F; The resistance of resistance R 1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18 is respectively 21.2 Ω; 42.4 Ω; 84.9 Ω; 106 Ω; 169.6 Ω; 212 Ω; 8.38 Ω; 16.76 Ω; 33.52 Ω; 41.9 Ω; 67.04 Ω; 83.8 Ω; 4.19 Ω; 8.38 Ω; 16.76 Ω; 20.95 Ω; 33.52 Ω; 41.9 Ω;
Capacitor C 4 in Zinc-Oxide Arrester total current and the current in resistance property generator circuit is 0.5775 μ F;
The resistance of resistance R 19, R20, R21 is respectively 57.057k Ω; 114.114k Ω; 288.7885k Ω;
Other is with embodiment 1.