CN109358597A - Thyristor control unit protectiveness triggers the equivalent test device of low pressure and control method - Google Patents
Thyristor control unit protectiveness triggers the equivalent test device of low pressure and control method Download PDFInfo
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- CN109358597A CN109358597A CN201811186877.9A CN201811186877A CN109358597A CN 109358597 A CN109358597 A CN 109358597A CN 201811186877 A CN201811186877 A CN 201811186877A CN 109358597 A CN109358597 A CN 109358597A
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- thyristor
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B23/00—Testing or monitoring of control systems or parts thereof
- G05B23/02—Electric testing or monitoring
- G05B23/0205—Electric testing or monitoring by means of a monitoring system capable of detecting and responding to faults
- G05B23/0218—Electric testing or monitoring by means of a monitoring system capable of detecting and responding to faults characterised by the fault detection method dealing with either existing or incipient faults
- G05B23/0221—Preprocessing measurements, e.g. data collection rate adjustment; Standardization of measurements; Time series or signal analysis, e.g. frequency analysis or wavelets; Trustworthiness of measurements; Indexes therefor; Measurements using easily measured parameters to estimate parameters difficult to measure; Virtual sensor creation; De-noising; Sensor fusion; Unconventional preprocessing inherently present in specific fault detection methods like PCA-based methods
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Abstract
The present invention provides a kind of equivalent test device of thyristor control unit protectiveness triggering low pressure and control method, including low-voltage module, current-limiting resistance, test thyristor, capacitance-resistance circuit, static voltage sharing, equalizing resistance in parallel, equalizing resistance switch in parallel, photoelectric conversion module, detection module, thyristor control unit TCU to be measured.When test, the lower equalizing resistance in parallel of resistance value is connected in parallel on static voltage sharing both ends, protectiveness triggering, conducting thyristor, while TCU can occur under lower pressure and send protectiveness triggering marker pulse IP return optical signal by TCU.IP return optical signal is converted to electric signal by photoelectric conversion module and send to detection module, while detection module acquires thyristor voltage, that is, can determine whether TCU protectiveness Trigger Function is normal.Test loop of the present invention is simple, is not necessarily to high-pressure generation equipment, builds conveniently, without high pressure in test process, realizes the TCU protectiveness triggering test under lower pressure, ensure that the safety of test.
Description
Technical field
The invention belongs to power equipment testing fields, trigger more particularly, to a kind of thyristor control unit protectiveness
The equivalent test device of low pressure and control method.
Background technique
With the rapid development of electric system, the application of power electronic technique in the power system is more mature and gos deep into.
D.C. high voltage transmission has many advantages, such as that power transmission efficiency is high, transmission line capability is big, system stability is good, is current remote in Technological Economy
The preferred plan of distance transmission of electricity；Thyristor switchable capacitor TSC, static passive compensation device SVC etc. are in power system reactive power tune
Section aspect plays particularly important effect；Static frequency changer SFC is the indispensable equipment of generator connecting in parallel with system power generation.Thyristor is made
For the core devices in these application scenarios, driving, protection all rely on thyristor control unit TCU.And reliable, efficient,
The TCU test method of safety is the important foundation that guarantees TCU and can operate normally.
In order to protect thyristor from high-voltage breakdown, protectiveness Trigger Function is mono- particularly important function of TCU.But it protects
The triggering of shield property needs condition of high voltage.Traditional test method needs to apply high pressure at thyristor both ends, in thyristor
Protectiveness triggering, conducting thyristor occur for moment TCU that both end voltage reaches protectiveness triggering threshold value, and return protectiveness touching
Send out IP.Ceiling voltage reaches even nearly 10,000 volts of thousands of volts in test.It needs to carry out high voltage protection and isolation in test process, need
Special high-pressure generation equipment is wanted, testing efficiency is low, and testing cost is higher, and there are security risks.Invent CN101982789A
A kind of novel method for testing low-voltage trigger of thyristor of direct-current converter valve proposed passes through control thyristor electronic equipment TE board
Trigger pulse triggers thyristor is sent, to test the low pressure Trigger Function of thyristor, but the protectiveness triggering for being not used to TCU is surveyed
Examination.
Summary of the invention
The object of the present invention is to provide a kind of equivalent test device of thyristor control unit protectiveness triggering low pressure and controls
Method realizes that the TCU protectiveness under lower pressure triggers test, to solve existing thyristor control unit protectiveness triggering test
Method needs to apply high pressure at thyristor both ends, and test loop builds complexity and haves the defects that security risk.
In order to achieve the above objectives, the present invention provides following solutions:
A kind of TCU protectiveness triggering equivalent test device of low pressure includes that low-voltage module, current-limiting resistance, test thyristor, capacitance-resistance are returned
Road, static voltage sharing, equalizing resistance in parallel, equalizing resistance switch in parallel, photoelectric conversion module, detection module, brilliant lock to be measured
Pipe control unit TCU.Low-voltage module, current-limiting resistance, Thyristors in series connection, thyristor both ends are parallel with capacitance-resistance circuit, capacitance-resistance
Circuit output is connected to TCU to be measured, and the anode of thyristor is connected to TCU to be measured by static voltage sharing, and the cathode of thyristor is direct
It is connected to TCU to be measured, the triggering of the gate pole of thyristor and TCU to be measured, which export, to be connected, and equalizing resistance in parallel passes through equal piezoelectricity in parallel
Resistance switch in parallel connects at static voltage sharing both ends, and the return marker pulse IP marker pulse of TCU to be measured sends optical port and passes through one
Root optical fiber is connected to photoelectric conversion module, photoelectric conversion module output access detection module, and the anode and cathode of thyristor accesses inspection
Survey module；
The low-voltage module is used to provide operating voltage to test thyristor and TCU to be measured；
The detection module is used to detect test thyristor both end voltage and the IP return signal of TCU to be measured, according to the crystalline substance of acquisition
Brake tube voltage change and IP pulse characteristics judge whether TCU protectiveness Trigger Function is normal.
Wherein, the electric current of circuit when current-limiting resistance is used to limit turn on thyristors；Capacitance-resistance circuit and static voltage sharing are
External loop necessary to TCU is worked normally.When carrying out protectiveness triggering test, the switch of equalizing resistance in parallel is closed, it will simultaneously
Connection equalizing resistance is connected in parallel on static voltage sharing both ends, and then TCU protectiveness triggers the equivalent reduction of threshold value, under lower pressure
Protectiveness triggering, conducting thyristor can occur, while sending protectiveness triggering IP return signal.
Further, the gate pole of the test thyristor needs the triggering with TCU to be measured to export connection, when TCU is protected
When the triggering of shield property, trigger pulse can trigger turn on thyristors, and then thyristor both end voltage can be reduced to 0V at once.
Further, the equalizing resistance in parallel passes through a switch in parallel at static voltage sharing both ends, and parallel connection is
Piezoresistance resistance value is much smaller than static voltage sharing resistance value.When the switches are opened, under lower pressure, protectiveness touching can not occur for TCU
Hair；When the switch is closed, under lower pressure, protectiveness triggering can occur for TCU, and trigger pulse can open test thyristor,
Test thyristor both end voltage is reduced to 0V immediately, meanwhile, TCU issues protectiveness triggering IP and returns optical signal.
Further, the photoelectric conversion module is connect with TCU by optical fiber, the IP return light letter for issuing TCU
It number is converted to electric signal and send to detection module；Detection module acquires thyristor both end voltage simultaneously.
According to a kind of TCU protectiveness triggering equivalent detecting method provided by the invention, equalizing resistance in parallel is connected in parallel on quiet
State equalizing resistance both ends, in low-voltage module power supply, protectiveness triggering can occur for TCU, trigger turn on thyristors, at this time thyristor
Both end voltage is reduced to 0V by positive voltage immediately；Meanwhile the protectiveness triggering IP return optical signal that TCU is issued passes through photoelectric conversion mould
Block is converted to electric signal and send to detection module.Detection module passes through the thyristor voltage variation detected and IP pulse signal is special
Sign can determine that protectiveness triggering tests whether to pass through.Therefore, under lower pressure, the protectiveness triggering that TCU can be completed is surveyed
Examination.
The control method of the TCU protectiveness triggering equivalent test device of low pressure specifically comprises the following steps:
Step 1: disconnecting equalizing resistance switch in parallel, low-voltage module is powered to TCU to be measured；
Protectiveness triggering does not occur for step 2:TCU, and thyristor voltage is complete sine wave voltage, while TCU sends forward voltage
Establish IP light pulse；
Step 3: being closed equalizing resistance switch in parallel, equalizing resistance in parallel is connected in parallel on static voltage sharing both ends, TCU is in low pressure
Under the conditions of protectiveness triggering can occur, trigger pulse can open test thyristor, and test thyristor both end voltage is reduced to immediately
0V, meanwhile, TCU issues protectiveness triggering IP and returns optical signal；
Step 4: detection module passes through the thyristor voltage variation detected and IP pulse signal feature can determine that protectiveness is touched
Hair tests whether to pass through.
Beneficial effects of the present invention: a kind of TCU protectiveness provided by the invention triggers low pressure equivalent detecting method, and existing
There is technology to compare to have the following beneficial effects:
1) test loop needed for is simple, is not necessarily to high-pressure generation equipment, builds conveniently；
2) without high pressure in test process, the TCU protectiveness triggering test under lower pressure is realized, ensure that the safety of test
Property；
3) testing cost is reduced, testing efficiency is improved.
Detailed description of the invention
Fig. 1 is that a kind of TCU protectiveness of the invention triggers equivalent test device functional block diagram；
Fig. 2 is that thyristor both end voltage waveform and TCU return IP signal schematic representation.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to the accompanying drawings and embodiments, right
The present invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, and
It is not used in the restriction present invention.As long as in addition, technical characteristic involved in the various embodiments of the present invention described below
Not constituting a conflict with each other can be combined with each other.
Fig. 1 is the equivalent test device functional block diagram of a kind of thyristor control unit protectiveness triggering of the invention, including such as
Lower module: low-voltage module 1, current-limiting resistance RX2, test thyristor Q16, capacitance-resistance circuit 7, static voltage sharing RZ5, parallel connection are pressed
Resistance RY3, equalizing resistance switch 4 in parallel, photoelectric conversion module 9, detection module 8, TCU10 to be measured.Low-voltage module, current-limiting resistance
RX, test thyristor Q1 are connected in series, and thyristor both ends are parallel with capacitance-resistance circuit, and the output of capacitance-resistance circuit is connected to TCU to be measured, brilliant lock
The anode of pipe is connected to TCU to be measured by static voltage sharing RZ, and the cathode of thyristor is directly connected to TCU to be measured, thyristor
The triggering output of gate pole and TCU to be measured connect, and equalizing resistance RY in parallel passes through equalizing resistance switch 4 in parallel and is connected in static equal
Piezoresistance both ends, the marker pulse IP of TCU to be measured send optical port and are connected to photoelectric conversion module, photoelectric conversion mould by an optical fiber
Block output access detection module, the anode and cathode of thyristor access detection module.
Fig. 2 is thyristor both end voltage waveform and TCU return IP signal schematic representation.
Low-voltage module 1 can be used a low-tension transformer and constitute, when equalizing resistance switch 4 in parallel disconnects, due to low
The voltage that die block is applied to the test both ends thyristor Q16 is lower, and protectiveness triggering will not occur for TCU, at this time thyristor
Both end voltage is complete sine wave, i.e., the voltage in 0 to the t1 period as shown in Figure 2, and in each sinusoidal voltage period
Interior, TCU can issue a forward voltage and establish IP pulse 11, this IP returns signal and occurs after sine voltage zero crossing not
Long, show that thyristor both ends have been set up forward voltage.
When equalizing resistance switch 4 in parallel closure when, equalizing resistance RY3 in parallel incite somebody to action and be connected in static voltage sharing RZ5 two
End, since the resistance value of equalizing resistance in parallel is much smaller than the resistance value of static voltage sharing, in low-voltage module power supply, TCU can be sent out
Raw protectiveness triggering, the trigger pulse meeting conducting thyristor that TCU is issued, then thyristor both end voltage is reduced to rapidly 0V, such as Fig. 2
Shown in voltage in t1 to t2 period.Meanwhile TCU can send protectiveness triggering IP return signal 13；In addition, in sine wave
After voltage over zero soon, TCU still can issue a forward voltage and establish IP pulse 12.Therefore, it triggers and tests in protectiveness
When, TCU can send two IP return signals within each sinusoidal voltage period.
The IP return signal that above-mentioned TCU is sent is converted to electric signal by photoelectric conversion module and send to detection module, simultaneously
Detection module also acquires thyristor both end voltage, according to the variation of the thyristor voltage of acquisition and IP pulse characteristics, that is, can determine whether
Whether TCU protectiveness Trigger Function is normal.
Test includes the following steps:
Step 1: disconnecting equalizing resistance switch in parallel, low-voltage module is powered to TCU to be measured；
Protectiveness triggering does not occur for step 2:TCU, and thyristor voltage is complete sine wave voltage, while TCU sends forward voltage
Establish IP light pulse；
Step 3: being closed equalizing resistance switch in parallel, equalizing resistance in parallel is connected in parallel on static voltage sharing both ends, TCU is in low pressure
Under the conditions of protectiveness triggering occurs, trigger pulse opens test thyristor, and test thyristor both end voltage is reduced to 0V immediately, together
When, TCU issues protectiveness triggering IP and returns optical signal；
Step 4: detection module passes through the thyristor voltage variation detected and IP pulse signal feature determines that protectiveness triggering is surveyed
Whether examination passes through.
As it will be easily appreciated by one skilled in the art that the foregoing is merely illustrative of the preferred embodiments of the present invention, not to
The limitation present invention, any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should all include
Within protection scope of the present invention.
Claims (7)
1. a kind of thyristor control unit protectiveness triggers the equivalent test device of low pressure, it is characterised in that: including low-voltage module, limit
Leakage resistance, test thyristor, capacitance-resistance circuit, static voltage sharing, equalizing resistance in parallel, equalizing resistance switch in parallel, photoelectricity turn
Change the mold block, detection module, thyristor control unit TCU to be measured；Low-voltage module, current-limiting resistance, Thyristors in series connection, thyristor
Both ends are parallel with capacitance-resistance circuit, and the output of capacitance-resistance circuit is connected to TCU to be measured, the anode of thyristor by static voltage sharing be connected to
TCU is surveyed, the cathode of thyristor is directly connected to TCU to be measured, and the triggering of the gate pole of thyristor and TCU to be measured, which export, to be connected, in parallel
Equalizing resistance is connect by equalizing resistance switch in parallel in parallel in static voltage sharing both ends, the return marker pulse IP of TCU to be measured
It sends optical port and photoelectric conversion module, photoelectric conversion module output access detection module, the sun of thyristor is connected to by an optical fiber
Pole and cathode access detection module；
The low-voltage module is used to provide operating voltage to test thyristor and TCU to be measured；
The detection module is used to detect test thyristor both end voltage and the IP return signal of TCU to be measured, according to the crystalline substance of acquisition
Brake tube voltage change and IP pulse characteristics judge whether TCU protectiveness Trigger Function is normal.
2. a kind of thyristor control unit protectiveness according to claim 1 triggers the equivalent test device of low pressure, feature
Be: the triggering output of the gate pole and TCU to be measured of the test thyristor connects, and when protectiveness triggering occurs for TCU, triggers arteries and veins
Punching can trigger turn on thyristors, and then thyristor both end voltage can be reduced to 0V at once.
3. a kind of thyristor control unit protectiveness according to claim 1 triggers the equivalent test device of low pressure, feature
Be: the parallel connection voltage sharing resistance value is much smaller than static voltage sharing resistance value.
4. a kind of thyristor control unit protectiveness according to claim 1 triggers the equivalent test device of low pressure, feature
Be: the photoelectric conversion module is connect with TCU by optical fiber, and the IP return optical signal for issuing TCU is converted to telecommunications
Number and send to detection module；Detection module acquires thyristor both end voltage simultaneously.
5. a kind of thyristor control unit protectiveness according to claim 1 triggers the equivalent test device of low pressure, feature
Be: the low-voltage module is low-tension transformer.
6. a kind of filled using the equivalent test of thyristor control unit protectiveness as described in any one in claim 1-5 triggering low pressure
The control method set, which is characterized in that equalizing resistance in parallel is connected in parallel on static voltage sharing both ends, is powered in low-voltage module
When, protectiveness triggering can occur for TCU, trigger turn on thyristors, thyristor both end voltage is reduced to 0V by positive voltage immediately at this time；Together
When, the protectiveness triggering IP return optical signal that TCU is issued is converted to electric signal by photoelectric conversion module and send to detection module；
Detection module passes through the thyristor voltage variation detected and IP pulse signal feature determines that protectiveness triggering tests whether to pass through.
7. a kind of controlling party of thyristor control unit protectiveness triggering equivalent test device of low pressure according to claim 6
Method, which is characterized in that the method specifically comprises the following steps:
Step 1: disconnecting equalizing resistance switch in parallel, low-voltage module is powered to TCU to be measured；
Protectiveness triggering does not occur for step 2:TCU, and thyristor voltage is complete sine wave voltage, while TCU sends forward voltage
Establish IP light pulse；
Step 3: being closed equalizing resistance switch in parallel, equalizing resistance in parallel is connected in parallel on static voltage sharing both ends, TCU is in low pressure
Under the conditions of protectiveness triggering occurs, trigger pulse opens test thyristor, and test thyristor both end voltage is reduced to 0V immediately, together
When, TCU issues protectiveness triggering IP and returns optical signal；
Step 4: detection module passes through the thyristor voltage variation detected and IP pulse signal feature determines that protectiveness triggering is surveyed
Whether examination passes through.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811186877.9A CN109358597A (en) | 2018-10-12 | 2018-10-12 | Thyristor control unit protectiveness triggers the equivalent test device of low pressure and control method |
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| CN201811186877.9A CN109358597A (en) | 2018-10-12 | 2018-10-12 | Thyristor control unit protectiveness triggers the equivalent test device of low pressure and control method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111208366A (en) * | 2020-01-09 | 2020-05-29 | 南京南瑞继保电气有限公司 | Method for judging electrification of high-voltage valve bank |
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| CN202004454U (en) * | 2010-04-30 | 2011-10-05 | 北京网联直流工程技术有限公司 | Testing system of direct-current power transmission converter and control protection equipment thereof |
| CN105510730A (en) * | 2015-11-25 | 2016-04-20 | 许继电气股份有限公司 | Testing apparatus and method for reverse recovery protection unit (RPU) of converter valve |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111208366A (en) * | 2020-01-09 | 2020-05-29 | 南京南瑞继保电气有限公司 | Method for judging electrification of high-voltage valve bank |
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