CN106526258A - Light three-phase voltage generator - Google Patents
Light three-phase voltage generator Download PDFInfo
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- CN106526258A CN106526258A CN201510583024.9A CN201510583024A CN106526258A CN 106526258 A CN106526258 A CN 106526258A CN 201510583024 A CN201510583024 A CN 201510583024A CN 106526258 A CN106526258 A CN 106526258A
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Abstract
The invention discloses a light three-phase voltage generator, which belongs to the technical field of power system relay protection, and particularly relates to a light three-phase voltage generator. The light three-phase voltage generator is small in size, light in weight and is applicable to a relay protection secondary circuit. The light three-phase voltage generator comprises a switch K3, and is structurally characterized in that one end of the switch K3 is connected with a power input terminal, and the other end of the switch K3 is connected with the input end of a self-coupling voltage regulator T2; the output end of the self-coupling voltage regulator T2 is connected with the input end of an isolation transformer T3; one end of the output end of the isolation transformer T3 is connected with one end of an adjustable resistor R14; the other end of the adjustable resistor R14 is connected with one end of a resistor R5; and the other end of the resistor R5 is respectively connected with one end of a resistor R6, one end of an adjustable resistor R10 and a voltage output terminal UA.
Description
Technical field
A kind of the invention belongs to Relay Protection Technology in Power System field, more particularly to light-duty three-phase voltage generator.
Background technology
Now with the construction of a large amount of intelligent substations; protection sampling is carried out in combining unit; place dispersion during failure amount is added using relay protection microcomputer tester to protection device; shift from one place to another sometimes for the job site by four or five ten jin heavy of microcomputer tester upstairs downstairs, it is arduously time-consuming to have a strong impact on work efficiency.
Some occasions; especially 66KV intelligent substations are in protective debugging; only need to add one group of three-phase main-frequency test current to carry out protecting the test of definite value or measured value; the power-up place of 66KV sides is at 66KV switch cubicle terminal blocks; then at the 10KV buses that the secondary switch of main transformer is located, job site is discrete, needs the Microcomputer Protection tester of tens kilogram weights for 10KV sides; shift from one place to another in different location, laborious time consuming work efficiency is low.
The content of the invention
The present invention is aiming at the problems referred to above, there is provided a kind of volume weight is little, be applied to the light-duty three-phase voltage generator of relay protection secondary circuit.
For achieving the above object, the present invention is adopted the following technical scheme that, the present invention includes switch K3, its structural feature switch K3 one end is connected with power input terminal, the switch K3 other ends are connected with the input from Rhizoma Nelumbinis pressure regulator T2, it is connected from the outfan of Rhizoma Nelumbinis pressure regulator T2 with the input of isolating transformer T3, outfan one end of isolating transformer T3 is connected with adjustable resistance R14 one end, the adjustable resistance R14 other ends are connected with resistance R5 one end, and the resistance R5 other ends are connected with resistance R6 one end, adjustable resistance R10 one end, output voltage terminals UA respectively；Resistance R6 other ends outfan centre cap respectively with isolating transformer T3, electric capacity C7 one end, adjustable resistance R12 one end, ground wire, electric capacity C11 one end, terminal UN is connected, the electric capacity C11 other ends are connected with the adjustable resistance R10 other ends, the electric capacity C7 other ends respectively with adjustable resistance R8 one end, output voltage terminals UC is connected, the adjustable resistance R8 other ends are connected with resistance R9 one end, the resistance R9 other ends outfan other end respectively with isolating transformer T3, electric capacity C14 one end is connected, the electric capacity C14 other ends respectively with resistance R13 one end, output voltage terminals UB is connected, the resistance R13 other ends are connected with the adjustable resistance R12 other ends.
Used as a kind of preferred version, switch K3 of the present invention adopts 2A air switch.
It is as another kind of preferred version, of the present invention to adopt 50W from Rhizoma Nelumbinis pressure regulator from Rhizoma Nelumbinis pressure regulator T2.
As another kind of preferred version, isolating transformer T3 of the present invention adopt 50W, no-load voltage ratio for 220/120/120 isolating transformer.
Secondly, adjustable resistance R14 of the present invention adopts 200 Europe, 5W adjustable resistances, resistance R5 adopts 0.5K Europe, 50W fixed resistances, resistance R6 adopts 0.6K ohms, 50W fixed resistances, resistance C7 adopts 5 μ F, 400VAC electric capacity, resistance R8 adopts 200 Europe, 5W adjustable resistances, resistance R9 adopts 1K Europe, 50W fixed resistances, resistance R10 adopts 200 Europe, 5W adjustable resistances, electric capacity C11 adopts 1 μ F, 400VAC electric capacity, resistance R12 adopts 200 Europe, 5W adjustable resistances, resistance R13 to adopt 0.5K Europe, 50W fixed resistances, electric capacity C14 to adopt 1 μ F, 400VAC electric capacity.
In addition, output voltage terminals UA of the present invention is connected with the UA terminals of protection terminal block, output voltage terminals UB is connected with the UB terminals of protection terminal block, and output voltage terminals UC is connected with the UC terminals of protection terminal block.
Beneficial effect of the present invention.
The present invention can be in the debugging of the engineering of digital transformer substation and Generic Substation, and the fixed value checking of debugging, route protection to backup auto-activating device, remote measurement amount play the effect got twice the result with half the effort to examination etc..Jing lot of experiments show that the parameter index of the present invention meets the needs of protective debugging, and output of the present invention meets the load-carrying requirement of institute, sine wave of the voltage waveform that the present invention is exported for standard.The present invention disclosure satisfy that the carrying load ability under all relay protection alternating voltage secondary circuit loading conditions, and meet error requirements.Present invention can apply in relay protection secondary circuit, be linked in protection terminal block.
R14, R of the present invention 5,6 three resistance of R can produce UA phase voltages by voltage divider principle；C7, R8, R9 can produce by capacitance-resistance parameter adjustment that amplitude is equal, and phase place is ahead of the UB phase voltages that UA is 240 degree；R12, R13, C14 can produce by capacitance-resistance parameter adjustment that amplitude is equal, and phase place is ahead of the UC phase voltages that UA is 120 degree.R10, C11 loop of the present invention can be finely adjusted to UA phase phase places, to reach the requirement determined in symmetrical precision of the phase place of UA, UB, UC.
Small-sized, light-duty low-power transformator is combined generation three-phase voltage, the three-phase alternating current symmetrical voltage for needed for relay protection of power system secondary circuit tests offer by patent of the present invention with resistive-capacitive voltage divider loop；The volume and weight of test apparatuses is made to be substantially reduced.
The present invention need not be using links such as traditional inversion, rectification, power amplifications, and simply using the link such as blood pressure lowering and resistive-capacitive voltage divider, loop constitutes simple.
Three-phase voltage output loop of the present invention be short-circuited phenomenon when, will not at all damage whole voltage generating loop, after short circuit phenomenon is eliminated, generator can recover normal immediately.
Present invention can apply to high impedance components and parts and loop.
Description of the drawings
The present invention will be further described with reference to the accompanying drawings and detailed description.The scope of the present invention is not only limited to the statement of herein below.
Fig. 1 is circuit theory diagrams of the present invention.
Fig. 2 is application connection figure of the present invention in relay protection work.
Fig. 3 is light-duty three-phase current generator circuit theory diagrams of the invention.
Fig. 4 is the voltage vector diagram after three-phase voltage generating loop of the present invention accesses protection voltage circuit.
Specific embodiment
As shown in the figure, the present invention includes switch K3, switch K3 one end is connected with power input terminal, the switch K3 other ends are connected with the input from Rhizoma Nelumbinis pressure regulator T2, it is connected from the outfan of Rhizoma Nelumbinis pressure regulator T2 with the input of isolating transformer T3, outfan one end of isolating transformer T3 is connected with adjustable resistance R14 one end, and the adjustable resistance R14 other ends are connected with resistance R5 one end, and the resistance R5 other ends are connected with resistance R6 one end, adjustable resistance R10 one end, output voltage terminals UA respectively；Resistance R6 other ends outfan centre cap respectively with isolating transformer T3, electric capacity C7 one end, adjustable resistance R12 one end, ground wire, electric capacity C11 one end, terminal UN is connected, the electric capacity C11 other ends are connected with the adjustable resistance R10 other ends, the electric capacity C7 other ends respectively with adjustable resistance R8 one end, output voltage terminals UC is connected, the adjustable resistance R8 other ends are connected with resistance R9 one end, the resistance R9 other ends outfan other end respectively with isolating transformer T3, electric capacity C14 one end is connected, the electric capacity C14 other ends respectively with resistance R13 one end, output voltage terminals UB is connected, the resistance R13 other ends are connected with the adjustable resistance R12 other ends.
The switch K3 adopts 2A air switch.
It is described to adopt 50W from Rhizoma Nelumbinis pressure regulator from Rhizoma Nelumbinis pressure regulator T2.
The isolating transformer T3 adopt 50W, no-load voltage ratio for 220/120/120 isolating transformer.One single-phase 220 volt alternating voltage is transformed to disclosure satisfy that the symmetrical test voltage of three-phase alternating current rather than single-phase AC voltage needed for relay protection of power system specialty by the present invention.
The adjustable resistance R14 adopts 200 Europe, 5W adjustable resistances, resistance R5 adopts 0.5K Europe, 50W fixed resistances, resistance R6 adopts 0.6K ohms, 50W fixed resistances, resistance C7 adopts 5 μ F, 400VAC electric capacity, resistance R8 adopts 200 Europe, 5W adjustable resistances, resistance R9 adopts 1K Europe, 50W fixed resistances, resistance R10 adopts 200 Europe, 5W adjustable resistances, electric capacity C11 adopts 1 μ F, 400VAC electric capacity, resistance R12 adopts 200 Europe, 5W adjustable resistances, resistance R13 adopts 0.5K Europe, 50W fixed resistances, electric capacity C14 to adopt 1 μ F, 400VAC electric capacity.Determine that above-mentioned parameter is configured by lot of experiments, when load impedance is 20K ohms, by the loop that above-mentioned parameter is configured, the error with producing no more than 3% after carrying, load capacity are strong, meet the thermally-stabilised requirement of longtime running.
The output voltage terminals UA is connected with the UA terminals of protection terminal block, and output voltage terminals UB is connected with the UB terminals of protection terminal block, and output voltage terminals UC is connected with the UC terminals of protection terminal block.
The present invention can be used cooperatively with light-duty three-phase current generator.
The light-duty three-phase current generator includes switching K1, the input of switch K1 is connected with alternating current input terminal, the outfan of switch K1 is connected with the input from Rhizoma Nelumbinis pressure regulator T1, it is connected from the outfan of Rhizoma Nelumbinis pressure regulator T1 with the input of isolating transformer T4, outfan one end of isolating transformer T4 is A phase output terminals, and A phase output terminals are passed sequentially through electric capacity C1, adjustable resistance R1, resistance R2 and be connected with A phase current lead-out terminals；First tap of isolating transformer T4 be B phase output terminals, B phase output terminals by switch K2 be connected with B phase current lead-out terminals；Second tap of isolating transformer T4 is C phase output terminals, and the C phases of isolating transformer T4 are exported and be connected with C phase current lead-out terminals by resistance R3, adjustable resistance R4.The light-duty three-phase current generator of the present invention can be in the debugging of the engineering of digital transformer substation and Generic Substation, and the fixed value checking of debugging, route protection to backup auto-activating device, remote measurement amount play the effect got twice the result with half the effort to examination etc..Jing lot of experiments draws; the parameter index of the light-duty three-phase current generator of the present invention meets the needs of protective debugging; the light-duty three-phase current generator output of the present invention meets the load-carrying requirement of institute, and the current waveform of light-duty three-phase current generator output of the invention is the sine wave of standard.The light-duty three-phase current generator of the present invention disclosure satisfy that the carrying load ability under all relay protection alternating current secondary circuit loading conditions, and meet error requirements.The light-duty three-phase current generator of the present invention is can be applicable in relay protection secondary circuit, is linked in protection terminal block.
The light-duty three-phase current generator of the present invention makes the resistance sum of adjustable resistance R1 and resistance R2 be equal to the 1/ of electric capacity C1 capacitive reactances by the size for adjusting adjustable resistance R1
Times, electric capacity C1, adjustable resistance R1, resistance R2 combine adjustment IA phase currents size and phase place and make 240 degree of the advanced IC of IA.Resistance R3 is combined adjustment IC phase current sizes with adjustable resistance R4.
Small-sized, light-duty low-power transformator, current transformer are combined generation three-phase alternating current, the three-phase alternating current symmetrical current for needed for relay protection of power system secondary circuit tests offer by the light-duty three-phase current generator of the present invention with phase adjustment loop.Thus, making the volume and weight of test apparatuses reduce more than ten times.The light-duty three-phase current generator size of the present invention is equivalent to common general-purpose table size.
The three-phase alternating current test current produced using light-duty three-phase current generator of the invention, need not be using links such as traditional inversion, rectification, power amplifications, and simply using links such as pressure regulation, phase adjustment and unsteady flows, loop constitutes simple.
The switch K2 adopts three-position switch, the struck side A of three-position switch is connected with the B phase output terminals, fixing end B of three-position switch is connected with the B phase currents lead-out terminal, fixing end C of three-position switch is connected with spare terminal, fixing end D of three-position switch is connected with input one end of power pack T5, the input other end of power pack T5 is connected with the outfan other end of the isolating transformer T4, and the outfan of power pack T5 is connected with fixed value checking terminal.Three-position switch has、, 0 three positions, when beatingDuring position, terminal AB leads to, and connects IB phase current output loops；When beatingDuring position, AD leads to, and connects the output loop of high current；When beating in 0 position, AC leads to, now no current output, and C is spare terminal.Power pack T5 parts are single-phase High-current output loop, and the loop can provide the fixed value checking function of excessively stream, fast tripping protection as subsidiary loop.
The isolating transformer T4 adopts 200W isolating transformers；The no-load voltage ratio of isolating transformer T4 is 220V/60V/60V/90V, when the input terminal voltage of isolating transformer T4 is 220V, between the B phase output terminals and A phase output terminals, voltage is 60V, between the C phase output terminals and B phase output terminals, voltage is 60V, and between the outfan other end and C phase output terminals of the isolating transformer T4, voltage is 90V.The light-duty three-phase current generator innovative point of the present invention is embodied in：By a single-phase 220 volt alternating current, simplest means are used, be transformed to disclosure satisfy that the symmetrical test current of three-phase alternating current needed for relay protection of power system specialty.
The power pack T5 adopts primary turns 25,5 circle of number of secondary turns, 50 watts of power current changers.Using the light-duty power pack of 50 watts of low-power, can further reduce the volume and weight of light-duty three-phase current generator of the invention.
The switch K1 exchanges air switch using 2A.
The A phase currents lead-out terminal is connected with the IA terminals of protection terminal block, and B phase currents lead-out terminal is connected with the IB terminals of protection terminal block, and C phase currents lead-out terminal is connected with the IC terminals of protection terminal block.
It is described to adopt 200W, 220V/250V from Rhizoma Nelumbinis pressure regulator from Rhizoma Nelumbinis pressure regulator T1.Cooperated with 200W isolating transformer T4 from Rhizoma Nelumbinis pressure regulator using 200W, be easy to limit the waveform of output current；The current waveform for making output is unsaturated, undistorted sine wave.
The electric capacity C1 adopts 122 microfarads, 400VAC electric capacity, adjustable resistance R1 to adopt 10 ohm of 50 watts of adjustable resistances, fixed resistances of the resistance R3 using 20 ohm of 50W, adjustable resistance R4 to adopt 15 ohm of 50 watts of adjustable resistances.Coordinated by above-mentioned parameter, IA, IB, IC output current of one group of three-phase symmetrical for being output as 1A and the monophase current of 20A all the way can be adjusted out.
It is understandable that, above with respect to the specific descriptions of this present invention, it is merely to illustrate this present invention and is not limited to the technical scheme described by this embodiment of the present invention, it will be understood by those within the art that, still this present invention can be modified or equivalent, to reach identical technique effect；As long as satisfaction uses needs, all within this protection scope of the present invention.
Claims (6)
1. light-duty three-phase voltage generator, including switch K3, it is characterized in that switch K3 one end is connected with power input terminal, the switch K3 other ends are connected with the input from Rhizoma Nelumbinis pressure regulator T2, it is connected from the outfan of Rhizoma Nelumbinis pressure regulator T2 with the input of isolating transformer T3, outfan one end of isolating transformer T3 is connected with adjustable resistance R14 one end, the adjustable resistance R14 other ends are connected with resistance R5 one end, and the resistance R5 other ends are connected with resistance R6 one end, adjustable resistance R10 one end, output voltage terminals UA respectively；Resistance R6 other ends outfan centre cap respectively with isolating transformer T3, electric capacity C7 one end, adjustable resistance R12 one end, ground wire, electric capacity C11 one end, terminal UN is connected, the electric capacity C11 other ends are connected with the adjustable resistance R10 other ends, the electric capacity C7 other ends respectively with adjustable resistance R8 one end, output voltage terminals UC is connected, the adjustable resistance R8 other ends are connected with resistance R9 one end, the resistance R9 other ends outfan other end respectively with isolating transformer T3, electric capacity C14 one end is connected, the electric capacity C14 other ends respectively with resistance R13 one end, output voltage terminals UB is connected, the resistance R13 other ends are connected with the adjustable resistance R12 other ends.
2. light-duty three-phase voltage generator according to claim 1, it is characterised in that the switch K3 adopts 2A air switch.
3. light-duty three-phase voltage generator according to claim 1, it is characterised in that it is described from Rhizoma Nelumbinis pressure regulator T2 using 50W from Rhizoma Nelumbinis pressure regulator.
4. light-duty three-phase voltage generator according to claim 1, it is characterised in that the isolating transformer T3 adopt 50W, no-load voltage ratio for 220/120/120 isolating transformer.
5. light-duty three-phase voltage generator according to claim 1, it is characterized in that the adjustable resistance R14 adopts 200 Europe, 5W adjustable resistances, resistance R5 adopts 0.5K Europe, 50W fixed resistances, resistance R6 adopts 0.6K ohms, 50W fixed resistances, resistance C7 adopts 5 μ F, 400VAC electric capacity, resistance R8 adopts 200 Europe, 5W adjustable resistances, resistance R9 adopts 1K Europe, 50W fixed resistances, resistance R10 adopts 200 Europe, 5W adjustable resistances, electric capacity C11 adopts 1 μ F, 400VAC electric capacity, resistance R12 adopts 200 Europe, 5W adjustable resistances, resistance R13 adopts 0.5K Europe, 50W fixed resistances, electric capacity C14 adopts 1 μ F, 400VAC electric capacity.
6. light-duty three-phase voltage generator according to claim 1; it is characterized in that the output voltage terminals UA is connected with the UA terminals of protection terminal block; output voltage terminals UB is connected with the UB terminals of protection terminal block, and output voltage terminals UC is connected with the UC terminals of protection terminal block.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510583024.9A CN106526258B (en) | 2015-09-15 | 2015-09-15 | Light three-phase voltage generator |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510583024.9A CN106526258B (en) | 2015-09-15 | 2015-09-15 | Light three-phase voltage generator |
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| CN106526258A true CN106526258A (en) | 2017-03-22 |
| CN106526258B CN106526258B (en) | 2023-06-09 |
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6087738A (en) * | 1998-08-20 | 2000-07-11 | Robicon Corporation | Variable output three-phase transformer |
| US20010048356A1 (en) * | 2000-01-12 | 2001-12-06 | Transformers And Phase Shifters, Inc. | Method and apparatus for providing selectable output voltages |
| CN2678083Y (en) * | 2004-01-16 | 2005-02-09 | 谷正国 | Small current switchover autoconnected streetlight transformer |
| CN201821315U (en) * | 2009-12-09 | 2011-05-04 | 北京水木源华电气有限公司 | Loaded voltage-adjusting control system of transformer |
| CN203164365U (en) * | 2013-01-28 | 2013-08-28 | 南京民盛电子仪器有限公司 | Voltage sampling circuit of voltage-withstand tester |
| CN103579985A (en) * | 2013-07-24 | 2014-02-12 | 都匀供电局 | Method and device for adjusting ice melting output voltage |
| CN104426383A (en) * | 2013-08-29 | 2015-03-18 | 大禹电气科技股份有限公司 | Autotransformer voltage regulator circuit |
| CN204945196U (en) * | 2015-09-15 | 2016-01-06 | 国网辽宁省电力有限公司沈阳供电公司 | Light-duty three-phase voltage generator |
-
2015
- 2015-09-15 CN CN201510583024.9A patent/CN106526258B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6087738A (en) * | 1998-08-20 | 2000-07-11 | Robicon Corporation | Variable output three-phase transformer |
| US20010048356A1 (en) * | 2000-01-12 | 2001-12-06 | Transformers And Phase Shifters, Inc. | Method and apparatus for providing selectable output voltages |
| CN2678083Y (en) * | 2004-01-16 | 2005-02-09 | 谷正国 | Small current switchover autoconnected streetlight transformer |
| CN201821315U (en) * | 2009-12-09 | 2011-05-04 | 北京水木源华电气有限公司 | Loaded voltage-adjusting control system of transformer |
| CN203164365U (en) * | 2013-01-28 | 2013-08-28 | 南京民盛电子仪器有限公司 | Voltage sampling circuit of voltage-withstand tester |
| CN103579985A (en) * | 2013-07-24 | 2014-02-12 | 都匀供电局 | Method and device for adjusting ice melting output voltage |
| CN104426383A (en) * | 2013-08-29 | 2015-03-18 | 大禹电气科技股份有限公司 | Autotransformer voltage regulator circuit |
| CN204945196U (en) * | 2015-09-15 | 2016-01-06 | 国网辽宁省电力有限公司沈阳供电公司 | Light-duty three-phase voltage generator |
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| CN106526258B (en) | 2023-06-09 |
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