CN102565662A - State detection device for high-potential thyristor - Google Patents
State detection device for high-potential thyristor Download PDFInfo
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- CN102565662A CN102565662A CN2012100684098A CN201210068409A CN102565662A CN 102565662 A CN102565662 A CN 102565662A CN 2012100684098 A CN2012100684098 A CN 2012100684098A CN 201210068409 A CN201210068409 A CN 201210068409A CN 102565662 A CN102565662 A CN 102565662A
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Abstract
The invention discloses a state detection device for a high-potential thyristor. The device comprises a detection circuit board and a detection resistor circuit, wherein the detection circuit board is connected with the detection resistor circuit and connected with a detected thyristor through the detection resistor circuit; the detection resistor circuit comprises detection resistors; the detection circuit board comprises two parallel branches, a first parallel branch comprises a first diode, and a second parallel branch comprises an optical fiber transmitter; when the detected thyristor withstands a forward voltage, current flows through the first diode in the detection circuit board to protect the optical fiber transmitter from withstanding over-high backward voltage; and when the detected thyristor withstands the backward voltage, the current flows through the optical fiber transmitter, the optical fiber transmitter transmits a signal through an optical fiber, and withstanding of the backward voltage by the detected thyristor is detected. The state detection device for the high-potential thyristor is applicable to a high-potential system, a special power circuit is not required to be provided for the detection circuit board, the state of the thyristor can be easily detected, and the optical fiber transmitter can reliably operate in the high-potential system.
Description
Technical field
The present invention relates to a kind of thyristor testing circuit, especially relate to a kind of simple and convenient thyristor condition checkout gear that is applicable to noble potential system in the high-voltage and high-power power electronic device of having used thyristor.
Background technology
In the high-voltage and high-power power electronic device of thyristor is arranged, often need to detect thyristor and whether puncture.Whether thyristor possesses the ability of bearing certain reverse voltage is the foundation of judging whether it punctures.On this basis, traditional detection method is several resistance of parallel connection at the two ends of thyristor to be detected, judges through detecting wherein the voltage of certain resistance whether thyristor bears reverse voltage; Perhaps optocoupler of series connection in parallel resistance judges through the phototriode on off operating mode that detects optocoupler whether thyristor bears reverse voltage.In the middle of prior art, apply in 07 month 17 days calendar year 2001 by Pi You state, and open on 02 20th, 2002, publication number is that this kind method has promptly been adopted in the Chinese invention patent application " a kind of thuristor working state detecting method " of CN1336555A.This disclosure of the Invention a kind of detection method of thuristor working state; Utilize the synchronizing signal that thyristor itself uses in the thyristor control device; Adopt single-chip microcomputer in the one-period of this synchronizing signal, the pressure drop at thyristor two ends to be detected, reflect the duty of thyristor with the thyristor pressure drop that records.
And by applying on Dec 21st, 2007 Beijing Artime Intelligent Control Co., Ltd; And open on 07 02nd, 2008, publication number is that to have proposed a kind of be that the testing circuit plate is directly from power taking source, thyristor two ends and the active detection method of power source special circuit arranged in CN101210949A Chinese invention patent application " complete shut-down of thyristor AC-AC frequency device break testing circuit ".The disconnected testing circuit of the complete shut-down of a kind of AC/AC (alternating current) variable-frequency system thyristor belongs to thyristor frequency conversion technology.Form by voltage detecting circuit and logic judging circuit.Wherein, the terminal voltage that is input as thyristor of voltage detecting circuit, the output signal is delivered to logic judging circuit, by the disconnected detection signal of logic judging circuit output complete shut-down.Voltage detecting circuit is realized the detection to the thyristor voltage, and logic judging circuit utilizes trigger pip and voltage detection signal to make logic determines, provides the make-and-break signal of thyristor.
The method of original detection resistive voltage need provide power circuit for testing circuit.This power supply or provide by the outside, or directly obtain from the noble potential thyristor.By the outside power supply is provided, must solves the electrical isolation problem, thyristor current potential of living in is high more, and then isolation voltage is high more, and this has increased the cost and the volume of device undoubtedly.Obtain the power supply of testing circuit, then its power taking source circuit more complicated from the noble potential thyristor.The method of original detection optocoupler phototriode on off operating mode then receives the restriction of the voltage isolation capabilities of photoelectrical coupler, and is no longer suitable when the thyristor current potential is higher than certain value.
Therefore, a kind of simple and convenient pick-up unit of thyristor state of noble potential system that can be applicable to of invention becomes the technical matters that needs to be resolved hurrily.
Summary of the invention
The purpose of this invention is to provide a kind of noble potential thyristor condition checkout gear, this device circuit is simple in structure, neither is required to be testing circuit special power circuit is provided, and can be applicable to the noble potential system well again.
The present invention specifically provides a kind of technic relization scheme of noble potential thyristor condition checkout gear, and a kind of noble potential thyristor condition checkout gear comprises: testing circuit plate and detection resistance circuit.Detect resistance circuit and link to each other with the testing circuit plate, the testing circuit plate links to each other with tested thyristor through detecting resistance circuit; Detect resistance circuit and comprise detection resistance; The testing circuit plate comprises two branch roads parallel with one another, and first parallel branch comprises first diode, and second parallel branch comprises fiber optic transmitter.When tested thyristor bore forward voltage, electric current flow through first diode in the testing circuit plate plate, did not bear too high reverse voltage with the protection fiber optic transmitter; When tested thyristor bore reverse voltage, electric current flow through fiber optic transmitter, and fiber optic transmitter is seen this signal off through optical fiber again, promptly detected tested thyristor and had born reverse voltage.
As the further improvement of a kind of noble potential thyristor of the present invention condition checkout gear technical scheme, the testing circuit plate also comprises the 3rd parallel branch.The 3rd parallel branch comprises stabilivolt.Fiber optic transmitter is parallelly connected with stabilivolt; When tested thyristor bears forward voltage; Stabilivolt with the voltage limit at the second parallel branch fiber optic transmitter two ends in the scope of setting; The forward current that the while stabilivolt will flow through the 3rd parallel branch is limited in the scope of setting, and over current fault does not take place the protection fiber optic transmitter.
Further improvement as a kind of noble potential thyristor of the present invention condition checkout gear technical scheme; Second parallel branch also comprises current-limiting resistance; Current-limiting resistance is with parallelly connected with stabilivolt again after fiber optic transmitter is connected each other, and current-limiting resistance is limited in the electric current of second parallel branch in the scope of setting again.
Further improvement as a kind of noble potential thyristor of the present invention condition checkout gear technical scheme; Detect resistance circuit and comprise that first detects the resistance and the second detection resistance; The first detection resistance and second detects resistance and is connected between tested thyristor and the testing circuit plate, and first detects resistance and second detects voltage needs selection suitable power and the resistance of resistance according to the noble potential system.
As the further improvement of a kind of noble potential thyristor of the present invention condition checkout gear technical scheme, the 3rd parallel branch comprises second diode, second diode and stabilivolt differential concatenation, and second diode is used to stop stabilivolt to flow through forward current.
As the further improvement of a kind of noble potential thyristor of the present invention condition checkout gear technical scheme, fiber optic transmitter directly is connected with the noble potential system.
As the further improvement of a kind of noble potential thyristor of the present invention condition checkout gear technical scheme, tested thyristor is that electricity triggers thyristor or light triggered thyristor.
Through implementing the technical scheme of a kind of noble potential thyristor of the invention described above condition checkout gear, have following technique effect:
1, fiber optic transmitter is directly inserted in the noble potential system, be not required to be the testing circuit plate power source special circuit is provided, just can detect the state that electricity triggers thyristor and light triggered thyristor simply and easily;
2, the optical fiber isolation combines with passive electric circuit, and technical scheme of the present invention is applicable to than higher current potential system;
3, the fiber optic transmitter overcurrent protection that adopts stabilivolt pressure limiting shunting to combine with the resistance current limliting has guaranteed fiber optic transmitter reliably working in the noble potential system.
Description of drawings
In order to be illustrated more clearly in the embodiment of the invention or technical scheme of the prior art; To do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art below; Obviously, the accompanying drawing in describing below only is some embodiments of the present invention, for those of ordinary skills; Under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is the synoptic diagram that is electrically connected of a kind of embodiment of prior art thuristor working state pick-up unit;
Fig. 2 is the synoptic diagram that is electrically connected of the disconnected a kind of embodiment of testing circuit of prior art thyristor AC-AC frequency device complete shut-down;
Fig. 3 is the circuit catenation principle figure of a kind of embodiment of noble potential thyristor condition checkout gear of the present invention;
Wherein: 1-noble potential thyristor condition checkout gear; 2-testing circuit plate; 3-detects resistance circuit; The tested thyristor of 4-; V1-first diode; V2-second diode; The V3-stabilivolt; The HP1-fiber optic transmitter; The R1-current-limiting resistance; R2-first detects resistance; R3-second detects resistance.
Embodiment
To combine the accompanying drawing in the embodiment of the invention below, the technical scheme in the embodiment of the invention will be carried out clear, intactly description.Obviously, described embodiment only is a part of embodiment of the present invention, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills are not making the every other embodiment that is obtained under the creative work prerequisite, all belong to the scope of the present invention's protection.
Shown in accompanying drawing 3; Provided the specific embodiment that a kind of noble potential thyristor of the present invention condition checkout gear specifically is applied in noble potential system thyristor state-detection in the high-voltage and high-power power electronic device, the present invention has been described further below in conjunction with accompanying drawing and specific embodiment.
A kind of embodiment is applied in the high-pressure high-power thyristor current transformer; This high-power thyristor current transformer is an a kind of typical noble potential system; The thyristor of this current transformer is triggered by pulse transformer, and high-pressure high-power thyristor element wherein to be detected just is in the noble potential system.
The circuit theory diagrams of a kind of embodiment of noble potential thyristor condition checkout gear of the present invention are shown in accompanying drawing 3, and noble potential thyristor condition checkout gear 1 comprises: testing circuit plate 2 and detection resistance circuit 3; Detect resistance circuit 3 and link to each other with testing circuit plate 2, testing circuit plate 2 links to each other with tested thyristor 4 through detecting resistance circuit 3 again; Detect resistance circuit 3 and comprise detection resistance; Testing circuit plate 2 comprises two branch roads parallel with one another: first parallel branch comprises the first diode V1, and second parallel branch comprises fiber optic transmitter HP1.When tested thyristor 4 bore forward voltage, electric current flow through the first diode V1 in testing circuit plate 2 plates, and HP1 does not bear too high reverse voltage with the protection fiber optic transmitter; When tested thyristor 4 bore reverse voltage, electric current flow through fiber optic transmitter HP1, and fiber optic transmitter HP1 sees this signal off through optical fiber again, promptly detected tested thyristor 4 and had born reverse voltage.
Second parallel branch further comprises current-limiting resistance R1, and current-limiting resistance R1 connects with fiber optic transmitter HP1 each other, and current-limiting resistance R1 is limited in the electric current of second parallel branch in certain scope again.Testing circuit plate 2 also further comprises the 3rd parallel branch, and the 3rd parallel branch comprises stabilivolt V3.Fiber optic transmitter HP1 is with parallelly connected with stabilivolt V3 again after current-limiting resistance R1 connects.When tested thyristor 4 bears forward voltage; Stabilivolt V3 with the voltage limit between the second parallel branch fiber optic transmitter HP1 and the current-limiting resistance R1 in certain scope; The forward current that while stabilivolt V3 will flow through the 3rd parallel branch is limited in certain scope, and over current fault does not take place protection fiber optic transmitter HP1.
Detect resistance circuit 3 and comprise that first detects the resistance R 2 and the second detection resistance R 3; The first detection resistance R 2 and second detects resistance R 3 and is connected between tested thyristor 4 and the testing circuit plate 2; First detects resistance R 2 and second detects voltage needs selection suitable power and the resistance of resistance R 3 according to the noble potential system.The 3rd parallel branch further comprises the second diode V2, the second diode V2 and stabilivolt V3 differential concatenation, and the second diode V2 is used to stop stabilivolt V3 to flow through forward current.Fiber optic transmitter HP1 directly is connected with the noble potential system.Tested thyristor 4 can trigger thyristor or light triggered thyristor for electricity.
The forward current of fiber optic transmitter HP1 has certain limitation, surpasses this restriction and possibly cause its damage.In embodiment, fiber optic transmitter HP1 is used to protect fiber optic transmitter HP1 that over current fault does not take place with parallelly connected with stabilivolt V3 again after current-limiting resistance R1 connects.Stabilivolt V3 can be with the voltage limit of fiber optic transmitter HP1 and current-limiting resistance R1 branch road in certain limit, and on this basis, current-limiting resistance R1 is limited in this branch current in the certain limit again, is about to forward current and is limited in the certain limit.
Above-mentioned passive thyristor condition checkout gear of isolating based on photoelectricity through will detecting the two ends that resistance is connected in parallel on tested thyristor, and is connected fiber optic transmitter with current-limiting resistance.When tested thyristor bears certain reverse voltage, there is certain electric current to flow through fiber optic transmitter, the optical fiber that is connected with fiber optic transmitter sends light signal to control system again.This device is not required to be the testing circuit plate power supply is provided through fiber optic transmitter is directly inserted in the noble potential system, detects the state that electricity triggers thyristor and light triggered thyristor simply and easily.The optical fiber isolation combines with passive electric circuit, and this device is applicable to than higher current potential system.The fiber optic transmitter overcurrent protection method that adopts stabilivolt pressure limiting shunting to combine with the resistance current limliting has further guaranteed fiber optic transmitter reliably working in the noble potential system.
The above only is preferred embodiment of the present invention, is not the present invention is done any pro forma restriction.Though the present invention discloses as above with preferred embodiment, yet be not in order to limit the present invention.Any those of ordinary skill in the art; Do not breaking away under the technical scheme scope situation of the present invention; All the method for above-mentioned announcement capable of using and technology contents are made many possible changes and modification to technical scheme of the present invention, or are revised as the equivalent embodiment of equivalent variations.Therefore, every content that does not break away from technical scheme of the present invention, according to technical spirit of the present invention to any simple modification that above embodiment did, be equal to replacement, equivalence changes and modify, all still belong in the scope that technical scheme of the present invention protects.
Claims (7)
1. a noble potential thyristor condition checkout gear is characterized in that, comprising: testing circuit plate (2) and detection resistance circuit (3); Described detection resistance circuit (3) links to each other with testing circuit plate (2), and described testing circuit plate (2) links to each other with tested thyristor (4) through detecting resistance circuit (3); Detect resistance circuit (3) and comprise detection resistance; Testing circuit plate (2) comprises two branch roads parallel with one another, and first parallel branch comprises first diode (V1), and second parallel branch comprises fiber optic transmitter (HP1); When tested thyristor (4) when bearing forward voltage, electric current flows through first diode (V1) in testing circuit plate (2) plate, does not bear too high reverse voltage with protection fiber optic transmitter (HP1); When tested thyristor (4) when bearing reverse voltage, electric current flows through fiber optic transmitter (HP1), and fiber optic transmitter (HP1) is seen this signal off through optical fiber again, promptly detects tested thyristor (4) and has born reverse voltage.
2. a kind of noble potential thyristor condition checkout gear according to claim 1, it is characterized in that: described testing circuit plate (2) also comprises the 3rd parallel branch, the 3rd parallel branch comprises stabilivolt (V3); Said fiber optic transmitter (HP1) is parallelly connected with stabilivolt (V3), when tested thyristor (4) when bearing forward voltage, said stabilivolt (V3) with the voltage limit at second parallel branch fiber optic transmitter (HP1) two ends in the scope of setting; The forward current that while stabilivolt (V3) will flow through the 3rd parallel branch is limited in the scope of setting, and over current fault does not take place protection fiber optic transmitter (HP1).
3. a kind of noble potential thyristor condition checkout gear according to claim 1 and 2; It is characterized in that: described second parallel branch also comprises current-limiting resistance (R1), and current-limiting resistance (R1) is with parallelly connected with stabilivolt (V3) again after fiber optic transmitter (HP1) is connected; Current-limiting resistance (R1) is limited in the electric current of second parallel branch in the scope of setting.
4. a kind of noble potential thyristor condition checkout gear according to claim 3 is characterized in that: said detection resistance circuit (3) comprises that first detects the resistance (R2) and the second detection resistance (R3); The described first detection resistance (R2) and second detects resistance (R3) and is connected between tested thyristor (4) and the testing circuit plate (2); First detects resistance (R2) and second detects voltage needs selection suitable power and the resistance of resistance (R3) according to the noble potential system.
5. a kind of noble potential thyristor condition checkout gear according to claim 4, it is characterized in that: described the 3rd parallel branch comprises second diode (V2); Said second diode (V2) and stabilivolt (V3) differential concatenation, second diode (V2) is used to stop stabilivolt (V3) to flow through forward current.
6. according to the described a kind of noble potential thyristor condition checkout gear of arbitrary claim in the claim 1,2,4,5, it is characterized in that: described fiber optic transmitter (HP1) directly is connected with the noble potential system.
7. a kind of noble potential thyristor condition checkout gear according to claim 6 is characterized in that: described tested thyristor (4) triggers thyristor or light triggered thyristor for electricity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210068409.8A CN102565662B (en) | 2012-03-15 | 2012-03-15 | State detection device for high-potential thyristor |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201210068409.8A CN102565662B (en) | 2012-03-15 | 2012-03-15 | State detection device for high-potential thyristor |
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| CN102565662A true CN102565662A (en) | 2012-07-11 |
| CN102565662B CN102565662B (en) | 2014-08-27 |
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| CN201210068409.8A Expired - Fee Related CN102565662B (en) | 2012-03-15 | 2012-03-15 | State detection device for high-potential thyristor |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102928758A (en) * | 2012-10-17 | 2013-02-13 | 株洲变流技术国家工程研究中心有限公司 | System and method for detecting state of anti-parallel thyristors |
| CN102970029A (en) * | 2012-11-06 | 2013-03-13 | 北京广利核系统工程有限公司 | High-safety digital quantity signal acquisition circuit |
| CN102998620A (en) * | 2012-12-17 | 2013-03-27 | 哈尔滨工业大学 | Device and method for quick online fault detection of high voltage thyristor valve block |
| CN103439640A (en) * | 2013-08-30 | 2013-12-11 | 株洲变流技术国家工程研究中心有限公司 | High-potential state detection device of anti-parallel thyristors |
| CN103457590A (en) * | 2013-08-30 | 2013-12-18 | 株洲变流技术国家工程研究中心有限公司 | Method for detecting internal overvoltage protection of light control thyristor and device for generating status signal |
| CN112034394A (en) * | 2020-11-03 | 2020-12-04 | 中南大学 | Rectifier open-circuit fault diagnosis method based on current half-wave difference and electronic equipment |
| CN114184922A (en) * | 2020-08-25 | 2022-03-15 | 中车株洲电力机车研究所有限公司 | System and method for detecting state of diode device |
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| CN102998620A (en) * | 2012-12-17 | 2013-03-27 | 哈尔滨工业大学 | Device and method for quick online fault detection of high voltage thyristor valve block |
| CN103439640A (en) * | 2013-08-30 | 2013-12-11 | 株洲变流技术国家工程研究中心有限公司 | High-potential state detection device of anti-parallel thyristors |
| CN103457590A (en) * | 2013-08-30 | 2013-12-18 | 株洲变流技术国家工程研究中心有限公司 | Method for detecting internal overvoltage protection of light control thyristor and device for generating status signal |
| CN103457590B (en) * | 2013-08-30 | 2016-10-05 | 株洲变流技术国家工程研究中心有限公司 | The detection method of photo thyristor built-in over-voltage protective and the generating means of status signal |
| CN114184922A (en) * | 2020-08-25 | 2022-03-15 | 中车株洲电力机车研究所有限公司 | System and method for detecting state of diode device |
| CN114184922B (en) * | 2020-08-25 | 2024-05-03 | 中车株洲电力机车研究所有限公司 | Diode device state detection system and method |
| CN112034394A (en) * | 2020-11-03 | 2020-12-04 | 中南大学 | Rectifier open-circuit fault diagnosis method based on current half-wave difference and electronic equipment |
| CN112034394B (en) * | 2020-11-03 | 2021-01-15 | 中南大学 | Rectifier open-circuit fault diagnosis method based on current half-wave difference and electronic equipment |
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