CN106526418B - A kind of conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control system, control method and Fault Locating Method - Google Patents
A kind of conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control system, control method and Fault Locating Method Download PDFInfo
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- CN106526418B CN106526418B CN201610974346.0A CN201610974346A CN106526418B CN 106526418 B CN106526418 B CN 106526418B CN 201610974346 A CN201610974346 A CN 201610974346A CN 106526418 B CN106526418 B CN 106526418B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
- G01R31/086—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution networks, i.e. with interconnected conductors
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J9/00—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
- H02J9/02—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which an auxiliary distribution system and its associated lamps are brought into service
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
- Y04S10/52—Outage or fault management, e.g. fault detection or location
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- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Direct Current Feeding And Distribution (AREA)
- Rectifiers (AREA)
- Supply And Distribution Of Alternating Current (AREA)
- Dc-Dc Converters (AREA)
Abstract
A kind of conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control system, including sequentially connected voltage transformer pt, control system, valve control system, converter valve are additionally provided with pulse-triggered exception judgment module in control system;The second phaselocked loop, Trigger Angle actual value monitoring modular are additionally provided in valve control system;Second phaselocked loop connect with voltage transformer pt and is commonly connected to Trigger Angle actual value monitoring modular with pulses switch module, and pulse-triggered exception judgment module is connect with trigger angle instruction module, Trigger Angle actual value monitoring modular respectively.Advantage is to realize high-voltage direct current converter valve trigger circuit closed-loop control.Establish converter valve trigger pulse angle and control pulse angle comparison result treatment mechanism.It realizes converter valve trigger pulse angle and controls fault location after pulse angle exception.
Description
Technical field
The present invention relates to technical field of HVDC transmission, a kind of particularly conventional high-pressure DC transmission system converter valve
Trigger circuit closed-loop control system, control method and Fault Locating Method.
Background technique
Conventional high-pressure DC transmission system based on thyristor valves is widely used in China, uses control system
System issues control pulse and issues trigger pulse to converter valve to converter valve valve control system, then by valve control system, and converter valve is connected
Mode realize DC transmission system run well as shown in Figure 1, to reach direct current system according to control require accurately it is right
The purpose that DC voltage, transimission power are controlled, however opened loop control shape of this control method still in no feedback at present
State, i.e. control system are issued to the control pulse of valve control, and valve control system has no feedback, are unable to ensure control system and issue control arteries and veins
Whether punching is consistent with the practical trigger pulse for being issued to converter valve of valve control, thus can not find that direct current system converter valve triggers in time
The abnormal conditions in circuit simultaneously avoid abnormal conditions from deepening in time, influence the safe and stable operation of direct current system.
Summary of the invention
The trigger circuit closed-loop control system with feedback function that the first purpose of the invention is to provide a kind of solves existing
There is system without feedback function, the problem for leading to not find direct current system exception in time.
A second object of the present invention is to provide a kind of based on the trigger circuit closed-loop control system with feedback function
Control method accurately obtains unusual condition in simple method, makes feedback information promptly and accurately.
Third object of the present invention is to provide a kind of based on the trigger circuit closed-loop control system with feedback function
Fault Locating Method can solve and be positioned in time when there is abnormal signal to the position of fault, can on-call maintenance processing.
First purpose to realize the present invention, the present invention propose a kind of following technical scheme: conventional high-pressure direct current transportation
System converter valve trigger circuit closed-loop control system, including sequentially connected voltage transformer pt, control system, valve control system,
Converter valve is equipped with the first phaselocked loop and trigger angle instruction module in the controls, and pulses switch is equipped in valve control system
Module and pulse distribution module MSC, the first phaselocked loop extract the phase signal of voltage transformer pt and are instructed according to trigger angle
The output signal of module, which combines, generates control pulse, and the pulses switch module that control pulse is sent to valve control system is converted into triggering
Pulse, trigger pulse are divided into multiple trigger pulses by pulse distribution module MSC and are sent to the multiple valve block triggerings of converter valve, control
Pulse-triggered exception judgment module is additionally provided in system;The second phaselocked loop, the monitoring of Trigger Angle actual value are additionally provided in valve control system
Module;Second phaselocked loop connect with voltage transformer pt and is commonly connected to Trigger Angle actual value monitoring mould with pulses switch module
Block, pulse-triggered exception judgment module are connect with trigger angle instruction module, Trigger Angle actual value monitoring modular respectively.
The triggering arteries and veins for passing through extraction pulses switch module output as the improvement of scheme one, Trigger Angle actual value monitoring modular
It rushes and processing is compared with the phase signal of the second phaselocked loop output, obtain Trigger Angle actual value α 1.
As the improvement of scheme two, pulse-triggered exception judgment module is by receiving the output of Trigger Angle actual value monitoring modular
α 1 and Trigger Angle instruction module output control pulse angle α 2 carry out logic judgment, logic judgment formula are as follows: | α 1- α 2 | >
λ, wherein λ is that trigger pulse angle detects worst error value.
As the improvement of scheme three, it is 0.25 degree that trigger pulse angle, which detects worst error value λ,.
As the improvement of any one of scheme one to four, control system and valve control system are double set Redundancy Designs, respectively
Active system and back-up system.
As the improvement of scheme five, control system further includes system switching module, lock modules, alarm module, and system is cut
Block is changed the mold to switchover operation between active system and back-up system;The capable of emitting locking order locking direct current of lock modules.
Second purpose to realize the present invention, the present invention propose a kind of following technical scheme: conventional high-pressure direct current transportation
The control method of system converter valve trigger circuit closed-loop control system, comprising the following steps:
1) voltage signal that voltage transformer pt detects is sent to control system, and the first phaselocked loop of control system extracts electricity
It presses the phase of signal to be combined simultaneously according to the control pulse angle α 2 that trigger angle instruction module issues and generates control pulse, control
Pulse, which is sent to valve control system control pulse and is sent to the pulses switch module of valve control system, is converted into trigger pulse, trigger pulse
It is divided into multiple trigger pulses by pulse distribution module MSC and is sent to the multiple valve block triggerings of converter valve;
2) valve control system Trigger Angle actual value monitoring modular, which is received, extracts voltage transformer pt output by the second phaselocked loop
The trigger pulse that the phase and pulses switch module of voltage signal issue can obtain Trigger Angle actual value α 1 by comparison;
3) pulse-triggered exception judgment module receives Trigger Angle actual value α 1 and control pulse angle α 2 makees logic judgment, has
Body judgment formula are as follows: | α 1- α 2 | > λ, wherein λ is that trigger pulse angle detects worst error value;
4) when step 3 judging result is set up, pulse-triggered exception judgment module issues abnormal signal.
Third purpose to realize the present invention, the present invention propose a kind of following technical scheme: conventional high-pressure direct current transportation
The Fault Locating Method of system converter valve trigger circuit closed-loop control system, comprising the following steps:
1) when active system or back-up system one issue abnormal signal, then the circuit between control system and valve control system goes out
It is now abnormal;
2) when active system and back-up system abnormal signal occur simultaneously, then abort situation is converter valve and its attached sets
It is standby.
The invention has the following advantages:
1, high-voltage direct current converter valve trigger circuit closed-loop control is realized.
2, converter valve trigger pulse angle and control pulse angle comparison result treatment mechanism are established.
3, it realizes converter valve trigger pulse angle and controls fault location after pulse angle exception.
Detailed description of the invention
Fig. 1 is existing high-voltage direct current converter valve trigger theory schematic diagram.
Fig. 2 is the schematic illustration of converter valve trigger circuit closed-loop control system of the invention.
Fig. 3 is the detection of converter valve trigger pulse angle and feedback principle schematic diagram of the invention.
Specific embodiment
Embodiment 1
As shown in Figure 2 and Figure 3, a kind of conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control system, including
Sequentially connected voltage transformer pt, control system, valve control system, converter valve, in the controls be equipped with the first phaselocked loop and
Trigger angle instruction module, is equipped with pulses switch module and pulse distribution module MSC in valve control system, and the first phaselocked loop extracts
The phase signal of voltage transformer pt simultaneously combines generation control pulse according to the output signal of trigger angle instruction module, controls arteries and veins
The pulses switch module that punching is sent to valve control system is converted into trigger pulse, and trigger pulse is divided by pulse distribution module MSC
Multiple trigger pulses are sent to the multiple valve block triggerings of converter valve, are additionally provided with pulse-triggered exception judgment module in control system;Valve
The second phaselocked loop, Trigger Angle actual value monitoring modular are additionally provided in control system;Second phaselocked loop is connect simultaneously with voltage transformer pt
Be commonly connected to Trigger Angle actual value monitoring modular with pulses switch module, pulse-triggered exception judgment module respectively with Trigger Angle
Spend instruction module, the connection of Trigger Angle actual value monitoring modular.
Trigger Angle actual value monitoring modular by extract pulses switch module output trigger pulse and with the second phaselocked loop
Processing is compared in the phase signal of output, obtains Trigger Angle actual value α 1.
Pulse-triggered exception judgment module is instructed by the α 1 and Trigger Angle for receiving the output of Trigger Angle actual value monitoring modular
The control pulse angle α 2 of module output carries out logic judgment, logic judgment formula are as follows: | α 1- α 2 | > λ, wherein λ is trigger pulse
Angle detects worst error value.It is 0.25 degree that trigger pulse angle, which detects worst error value λ,.
Control system and valve control system are double set Redundancy Designs, respectively active system and back-up system.
Control system further includes system switching module, lock modules, alarm module, system switching module to active system with
Switchover operation between back-up system;The capable of emitting locking order locking direct current of lock modules.
Embodiment 2
A kind of control method of conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control system, including it is following
Step:
1) voltage signal that voltage transformer pt detects is sent to control system, and the first phaselocked loop of control system extracts electricity
It presses the phase of signal to be combined simultaneously according to the control pulse angle α 2 that trigger angle instruction module issues and generates control pulse, control
Pulse, which is sent to valve control system control pulse and is sent to the pulses switch module of valve control system, is converted into trigger pulse, trigger pulse
It is divided into multiple trigger pulses by pulse distribution module MSC and is sent to the multiple valve block triggerings of converter valve;
2) valve control system Trigger Angle actual value monitoring modular, which is received, extracts voltage transformer pt output by the second phaselocked loop
The trigger pulse that the phase and pulses switch module of voltage signal issue can obtain Trigger Angle actual value α 1 by comparison;
3) pulse-triggered exception judgment module receives Trigger Angle actual value α 1 and control pulse angle α 2 makees logic judgment, has
Body judgment formula are as follows: | α 1- α 2 | > λ, wherein λ is that trigger pulse angle detects worst error value;
4) when step 3 judging result is set up, pulse-triggered exception judgment module issues abnormal signal.
Embodiment 3
A kind of Fault Locating Method of conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control system, including
Following steps:
1) when active system or back-up system one issue abnormal signal, then the circuit between control system and valve control system goes out
It is now abnormal;
2) when active system and back-up system abnormal signal occur simultaneously, then abort situation is converter valve and its attached sets
It is standby.
Above-listed detailed description is illustrating for possible embodiments of the present invention, and the embodiment is not to limit this hair
Bright the scope of the patents, all equivalence enforcements or change without departing from carried out by the present invention, is intended to be limited solely by the scope of the patents of this case.
Claims (8)
1. a kind of conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control system, including sequentially connected voltage are mutual
Sensor
PT, control system, valve control system, converter valve are equipped with the first phaselocked loop in the control system and trigger angle refer to
Module is enabled, pulses switch module and pulse distribution module MSC are equipped in the valve control system, the first phaselocked loop extracts voltage
The phase signal of mutual inductor PT simultaneously combines generation control pulse, control pulse hair according to the output signal of trigger angle instruction module
The pulses switch module for being sent to valve control system is converted into trigger pulse, and trigger pulse is divided into multiple by pulse distribution module MSC
Trigger pulse is sent to the multiple valve block triggerings of converter valve, it is characterised in that: it is different to be additionally provided with pulse-triggered in the control system
Normal judgment module;The second phaselocked loop, Trigger Angle actual value monitoring modular are additionally provided in the valve control system;Second lock
Xiang Huanyu voltage transformer pt connects and is commonly connected to Trigger Angle actual value monitoring modular, the arteries and veins with pulses switch module
Punching triggers abnormal judgment module and connect respectively with trigger angle instruction module, Trigger Angle actual value monitoring modular.
2. conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control system according to claim 1, special
Sign is: the Trigger Angle actual value monitoring modular is by extracting the trigger pulse of pulses switch module output and locking with second
Processing is compared in the phase signal of phase ring output, obtains Trigger Angle actual value α 1.
3. conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control system according to claim 2, special
Sign is: the α 1 and Trigger Angle that the pulse-triggered exception judgment module is exported by receiving Trigger Angle actual value monitoring modular
The control pulse angle α 2 of instruction module output carries out logic judgment, the logic judgment formula are as follows: | α 1- α 2 | > λ, wherein λ
Worst error value is detected for trigger pulse angle.
4. conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control system according to claim 3, special
Sign is: the trigger pulse angle detection worst error value λ is 0.25 degree.
5. conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control according to any one of claims 1 to 4
System, it is characterised in that: the control system and valve control system are double set Redundancy Designs, respectively active system and spare
System.
6. conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control system according to claim 5, special
Sign is: the control system further includes system switching module, lock modules, alarm module, the system switching module
To switchover operation between active system and back-up system;The capable of emitting locking order locking direct current of the lock modules.
7. one kind includes conventional high-pressure DC transmission system converter valve trigger circuit closed loop as claimed in any one of claims 1 to 6
The control method of control system, it is characterised in that: the following steps are included:
1) voltage signal that voltage transformer pt detects is sent to control system, and the first phaselocked loop of control system extracts voltage letter
Number phase simultaneously according to trigger angle instruction module issue control pulse angle α 2 combine generate control pulse, control pulse
The pulses switch module for being sent to valve control system is converted into trigger pulse, and trigger pulse is divided into more by pulse distribution module MSC
A trigger pulse is sent to the multiple valve block triggerings of converter valve;
2) valve control system Trigger Angle actual value monitoring modular receives the voltage that voltage transformer pt output is extracted by the second phaselocked loop
The trigger pulse that the phase and pulses switch module of signal issue can obtain Trigger Angle actual value α 1 by comparison;
3) pulse-triggered exception judgment module receives Trigger Angle actual value α 1 and control pulse angle α 2 makees logic judgment, specifically sentences
Disconnected formula are as follows: | α 1- α 2 | > λ, wherein λ is that trigger pulse angle detects worst error value;
4) when step 3 judging result is set up, pulse-triggered exception judgment module issues abnormal signal.
8. one kind includes conventional high-pressure DC transmission system converter valve trigger circuit closed loop as claimed in any one of claims 1 to 6
The Fault Locating Method of control system, it is characterised in that: the following steps are included:
1) when active system or back-up system one issue abnormal signal, then the circuit between control system and valve control system occurs different
Often;
2) when active system and back-up system abnormal signal occur simultaneously, then abort situation is converter valve and its auxiliary device.
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CN201610974346.0A CN106526418B (en) | 2016-11-04 | 2016-11-04 | A kind of conventional high-pressure DC transmission system converter valve trigger circuit closed-loop control system, control method and Fault Locating Method |
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CN107171353B (en) * | 2017-06-15 | 2020-03-20 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Light control valve control method for preventing current from being unable to be established during direct current unlocking |
CN110571839B (en) * | 2019-08-05 | 2023-06-20 | 华南理工大学 | High-voltage direct-current fault recovery method based on commutation voltage phase detection |
CN111384721B (en) * | 2020-02-24 | 2021-10-12 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | System and method for controlling redundancy switching of conventional direct-current transmission electrode |
CN111398765B (en) * | 2020-04-01 | 2022-05-17 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Thyristor triggering abnormity protection method for direct current transmission system |
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CN103149925A (en) * | 2013-03-01 | 2013-06-12 | 南京南瑞继保电气有限公司 | Dynamic simulation experimental platform of thyristor trigger control |
CN103530453A (en) * | 2013-09-30 | 2014-01-22 | 南方电网科学研究院有限责任公司 | Analysis method for locking of extra-high voltage direct current system caused by lightning strike on transmission line |
CN105242663A (en) * | 2015-10-23 | 2016-01-13 | 许继电气股份有限公司 | Converter valve return-pulse dynamic performance simulation system |
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- 2016-11-04 CN CN201610974346.0A patent/CN106526418B/en active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
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CN103149925A (en) * | 2013-03-01 | 2013-06-12 | 南京南瑞继保电气有限公司 | Dynamic simulation experimental platform of thyristor trigger control |
CN103530453A (en) * | 2013-09-30 | 2014-01-22 | 南方电网科学研究院有限责任公司 | Analysis method for locking of extra-high voltage direct current system caused by lightning strike on transmission line |
CN105242663A (en) * | 2015-10-23 | 2016-01-13 | 许继电气股份有限公司 | Converter valve return-pulse dynamic performance simulation system |
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