CN104038124A - Excitation control system based on double exciting windings - Google Patents
Excitation control system based on double exciting windings Download PDFInfo
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- CN104038124A CN104038124A CN201410250815.5A CN201410250815A CN104038124A CN 104038124 A CN104038124 A CN 104038124A CN 201410250815 A CN201410250815 A CN 201410250815A CN 104038124 A CN104038124 A CN 104038124A
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- Prior art keywords
- excitation winding
- excitation
- generator
- control system
- system based
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P7/00—Arrangements for regulating or controlling the speed or torque of electric DC motors
- H02P7/06—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P9/00—Arrangements for controlling electric generators for the purpose of obtaining a desired output
- H02P9/14—Arrangements for controlling electric generators for the purpose of obtaining a desired output by variation of field
- H02P9/26—Arrangements for controlling electric generators for the purpose of obtaining a desired output by variation of field using discharge tubes or semiconductor devices
- H02P9/30—Arrangements for controlling electric generators for the purpose of obtaining a desired output by variation of field using discharge tubes or semiconductor devices using semiconductor devices
Abstract
The invention discloses an excitation control system based on double exciting windings and belongs to the field of generator excitation control. The excitation control system based on the double exciting windings comprises a main exciting winding and an auxiliary exciting winding, which are coupled through a rotor core. The main exciting winding is used for providing a rotating magnetic field for a generator under non-force excitation working conditions, and the auxiliary exciting winding is used for providing a rotating magnetic field for the generator under force excitation working conditions for achieving force excitation. The excitation control system based on the double exciting windings improves the power factor of the load of an excitation system, reduces the harmonic current of an excitation power source, losses of an exciting transformer and the commutation peak overvoltage of a thyristor, enables existing field circuit breakers to be applied to large generator units, particularly the exciting systems of half-speed nuclear power shunt excitation generator units, improves the reliability and safety and meanwhile guarantees reliable operation of the generator units.
Description
Technical field
The invention belongs to generator excitation control field, relate in particular to a kind of exciter control system based on two excitation winding.
Background technology
Along with China's power construction is advanced by leaps and bounds, at the single-machine capacity of building generator unit, improve rapidly, the regenerative resources such as while nuclear energy, water energy, wind energy, solar energy and biomass energy are also in develop rapidly.In jumbo water power, thermoelectricity, nuclear power generating sets, owing to thering is larger rated excitation power supply and rated exciting current, the service behaviour indexs such as the excitation transformer in generator excited system, field circuit breaker, power cabinet and reliability requirement have been proposed to more and more higher requirement.
The transformer of generator or generator-transformer group is inner; and generator end is when being short-circuited accident between generator or generator-transformer group circuit breaker; relaying protection will be moved tripping operation; but short dot does not excise after generator or generator-transformer group circuit breaker trip, the induced potential that generator rotor field electric current produces continues to maintain fault current.Continuing of short circuit, can cause that insulation burns out, conductor fusing or scaling loss iron core, within the very short duration, often also may cause the badly damaged of generator, transformer, and likely make accident expand rapidly.The measure of avoiding or reducing device damage and restriction fault spread is that generator is carried out to quick de-excitation, makes the exciting current of generator be reduced to zero within the short as far as possible time.What adopt at present extensively is that move can type demagnetization, by the effect (ac de-excitation mode still being had to the effect of alternating voltage) of field circuit breaker disjunction arc voltage, makes rotor current be transferred to by the loop forming with field circuit breaker the loop forming with de-excitation resistance.After electric current shifts completely, field circuit breaker breaking current is the zero arc disjunction that ceases, and cuts off rotor-exciting power supply, and generator amature and de-excitation resistance form closed-loop path.For realizing rotor current, to de-excitation resistance loop, shifted demagnetization disjunction completely, the demagnetization disjunction arc voltage of field circuit breaker, ceiling voltage and the demagnetization that should be not less than de-excitation resistance start exciting power rectifier output voltage sum.
Safety requirements due to thyristor device under the requirement of the high initial voltage response speed of excitation system and large capacity conditions, has become main flow excitation mode from shunt excitation mode.For mega kilowatt nuclear power generators self-shunt excitation system, because the coal-fired turbo generator set of the more conventional 1000MW of its rated exciting current or 700MW hydraulic generator unit will be twice left and right, thus give eliminating magnetism of generator particularly field circuit breaker breaking capacity have higher requirement.And adopt existing field circuit breaker and traditional its breaking capacity of direct current demagnetization scheme to be difficult to meet the Generator Set needs of demagnetization safely and fast.
In the design process of excitation system, conventionally need to consider to guarantee that unit has enough abilities of encouraging by force, consider the excitation system of excitation forcing ratio, in parts selection design, just require higher electric current and voltage requirement.Especially for heavy-duty generator group, excitation system needs jumbo excitation transformer and power conversion unit, although there is not bottleneck in its technology, and the problem that the increase of capacity has brought reliability to reduce.
Requirements at the higher level for large capacity unit to excitation system reliability and safety, simple rely on the lifting of field circuit breaker, excitation transformer performance to be obviously difficult to meet the demands, in the urgent need to guaranteeing, under large capacity, guarantee the safe, reliable and effective method that realizes its function of excitation system.
Summary of the invention
In order to solve existing field circuit breaker and traditional its breaking capacity of direct current demagnetization scheme, be difficult to meet the Generator Set problem that capital equipment reliability reduces in the needs of demagnetization and Generator Set safely and fast, the invention provides a kind of exciter control system based on two excitation winding.
A kind of exciter control system based on two excitation winding, comprise main excitation winding and secondary excitation winding, the magnetic field of main excitation winding and secondary excitation winding is coupled by iron core, main excitation winding magnetic field is for providing generator at non-excitation field of encouraging by force under operating mode, secondary excitation winding is for dropping into encouraging by force under operating mode at generator, and secondary excitation winding excitation field superposes with main excitation winding excitation field.
Also comprise voltage regulator, voltage regulator is controlled respectively the power output of the power conversion part of main excitation winding and secondary excitation winding.
Described secondary excitation winding comprises Closing Switch, and Closing Switch is in parallel with secondary excitation winding.
Described secondary excitation winding arranges separately field power supply or shares with described main excitation winding.
Between the field power supply of described secondary excitation winding and secondary excitation winding, install gating switch or disconnecting link.
The present invention is with respect to the exciter control system that only has an excitation winding, two excitation winding loops have reduced the requirement to the capacity of excitation transformer and field circuit breaker disjunction voltage, improved the power factor of excitation system load, reduced the harmonic current of field power supply, reduced the loss of excitation transformer, reduced thyristor commutation peak overvoltage, make existing field circuit breaker can be applicable to Generator Set, particularly Half Speed nuclear power is from the excitation system of shunt excitation unit, improve reliability and the fail safe of exciter control system, also guaranteed the reliability service of generating set simultaneously.
Accompanying drawing explanation
Fig. 1 is the schematic diagram in the present invention;
Fig. 2 is the schematic diagram of embodiment bis-in the present invention.
Embodiment
As shown in Figure 1, exciter control system based on two excitation winding comprises main excitation winding L1 and secondary excitation winding L2, the magnetic field of main excitation winding L1 and secondary excitation winding L2 is by the iron core stack that is coupled, main excitation winding L1 provides non-generator excitation magnetic field of encouraging by force under operating mode, secondary excitation winding L2 encourages by force under operating mode and comes into operation at generating set, with main excitation winding L1 magnetic field superposition, jointly provide and encourage by force generator excitation magnetic field under operating mode.
Main excitation winding L1 and secondary excitation winding L2 have separately independently energized circuit.Field power supply Ef1 provides exciting current through excitation transformer 1, power conversion part 1 to main excitation winding L1, and at DC side installing field circuit breaker 1, demagnetization and overvoltage protection loop 1 are in parallel with main excitation winding L1; Field power supply Ef2 provides exciting current through excitation transformer 2, power conversion part 2 to secondary excitation winding L2, at DC side installing field circuit breaker 2, demagnetization and overvoltage protection loop 2 are in parallel with secondary excitation winding L2, for guarantee secondary excitation winding L2 in the situation that not coming into operation in closure state, Closing Switch is in parallel with secondary excitation winding L2; Voltage regulator AVR unifies to control according to operation state of generator to power conversion part 1 and power conversion part 2.Excitation transformer 1 can be in parallel at primary side with excitation transformer 2.One side installing gating switch or disconnecting link of excitation transformer 2.Secondary excitation winding L2 need not access closed-loop path while coming into operation, and by Closing Switch, realizes, and in situation about coming into operation, disconnects Closing Switch, so both can prevent winding induction overvoltage, can increase the damping of unit yet.
As shown in Figure 2, for embodiments of the invention two, embodiment bis-compares with embodiment mono-technology, secondary excitation winding L2 field power supply is different, in the present embodiment, secondary excitation winding L2 field power supply Ef2 arranges separately, receive other station service loops or take from station service, while adopting station service to avoid short-circuit of machine's port, encouraging by force the defect of scarce capacity.
In the situation of normal work, only have on main excitation winding L1 and have electric current to flow through, for generator provides generating required rotating magnetic field, secondary excitation winding L2 forms closed-loop path by Closing Switch; When generator need to be encouraged by force, closed gating switch disconnects the closed-loop path of secondary excitation winding L2 simultaneously, drops into secondary excitation winding L2; The magnetic field of two windings is coupled and is jointly provided generator required rotating magnetic field by iron core.Main excitation winding L1 and secondary excitation winding L2 have separately independently demagnetization and overvoltage protection loop, in the situation that needing separately demagnetization and overvoltage protection, drop into.
Main excitation winding L1 is operated in the non-operating mode of encouraging by force, and the parameters such as its excitation transformer 1 capacity, field circuit breaker 1 disjunction voltage can be carried out design selection by the parameter under generator rated condition; Owing to encouraging by force operating mode, it is not long-term continuous duty, secondary excitation winding L2 just comes into operation when needs unit is encouraged by force, and the short time duty that the parameters such as its excitation transformer 2 capacity, field circuit breaker 2 disjunction voltages can be encouraged by force requirement by generator carries out design selection.The energy storage during according to winding work separately of the de-excitation resistance capacity of two excitation winding is determined.The overvoltage protection loop operating value of two excitation winding is also designed by the pressure request of crossing of winding separately.
With respect to the exciter control system that only has an excitation winding, excitation transformer secondary side voltage in two excitation winding systems can reduce near half, each winding bears to such an extent that maximum voltage is also dropped by nearly half, particularly consider commutation peak overvoltage, winding insulation bears to such an extent that overvoltage level is even reduced to below half, and the insulation safety level of system can be greatly provided; Two excitation winding loops have reduced the requirement to the capacity of excitation transformer and field circuit breaker disjunction voltage simultaneously, improved the power factor of excitation load, reduced the harmonic current of field power supply, reduced the loss of excitation transformer, reduced thyristor commutation peak overvoltage, make existing field circuit breaker can be applicable to Generator Set, particularly Half Speed nuclear power is from the excitation system of shunt excitation unit, improve reliability and the fail safe of exciter control system, also guaranteed the reliability service of generating set simultaneously.
Claims (5)
1. the exciter control system based on two excitation winding, it is characterized in that, comprise main excitation winding and secondary excitation winding, the magnetic field of main excitation winding and secondary excitation winding is coupled by iron core, main excitation winding magnetic field is for providing generator at non-excitation field of encouraging by force under operating mode, secondary excitation winding is for dropping into encouraging by force under operating mode at generator, and secondary excitation winding excitation field superposes with main excitation winding excitation field.
2. according to right, want the exciter control system based on two excitation winding described in ball 1, it is characterized in that, also comprise voltage regulator, voltage regulator is controlled respectively the power output of the power conversion part of main excitation winding and secondary excitation winding.
3. according to right, want the exciter control system based on two excitation winding described in ball 1, it is characterized in that, described secondary excitation winding comprises Closing Switch, and Closing Switch is in parallel with secondary excitation winding.
4. according to right, want the exciter control system based on two excitation winding described in ball 1, it is characterized in that, described secondary excitation winding arranges separately field power supply or shares with described main excitation winding.
5. according to right, want the exciter control system based on two excitation winding described in ball 4, it is characterized in that, between the field power supply of described secondary excitation winding and secondary excitation winding, install gating switch or disconnecting link.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410250815.5A CN104038124B (en) | 2014-06-06 | 2014-06-06 | Exciter control system based on double Exciting Windings for Transverse Differential Protection |
| PCT/CN2014/086196 WO2015184697A1 (en) | 2014-06-06 | 2014-09-10 | Excitation system based on double excitation windings |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410250815.5A CN104038124B (en) | 2014-06-06 | 2014-06-06 | Exciter control system based on double Exciting Windings for Transverse Differential Protection |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104038124A true CN104038124A (en) | 2014-09-10 |
| CN104038124B CN104038124B (en) | 2017-07-07 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410250815.5A Active CN104038124B (en) | 2014-06-06 | 2014-06-06 | Exciter control system based on double Exciting Windings for Transverse Differential Protection |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN104038124B (en) |
| WO (1) | WO2015184697A1 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104362919A (en) * | 2014-11-27 | 2015-02-18 | 南车资阳机车有限公司 | Excitation device for synchronizing main generator and auxiliary generator and control method of excitation device |
| CN104821757A (en) * | 2015-04-10 | 2015-08-05 | 国电南瑞科技股份有限公司 | Synchronous motor excitation system control method based on real-time state internal potential control |
| CN105099308A (en) * | 2015-09-22 | 2015-11-25 | 东方电机控制设备有限公司 | Generator excitation device |
| CN105141206A (en) * | 2015-08-14 | 2015-12-09 | 柳州佳力电机股份有限公司 | Self-excited excitation system for large and medium-sized high-voltage generators |
| CN114094897A (en) * | 2020-07-31 | 2022-02-25 | 华为技术有限公司 | Radio excitation system, detection method and electric automobile |
| CN114172420A (en) * | 2021-11-26 | 2022-03-11 | 苏州热工研究院有限公司 | Rotor coupling double-machine parallel motor generator set complete set and protection control system |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104362919A (en) * | 2014-11-27 | 2015-02-18 | 南车资阳机车有限公司 | Excitation device for synchronizing main generator and auxiliary generator and control method of excitation device |
| CN104821757A (en) * | 2015-04-10 | 2015-08-05 | 国电南瑞科技股份有限公司 | Synchronous motor excitation system control method based on real-time state internal potential control |
| CN104821757B (en) * | 2015-04-10 | 2017-02-08 | 国电南瑞科技股份有限公司 | Synchronous motor excitation system control method based on real-time state internal potential control |
| CN105141206A (en) * | 2015-08-14 | 2015-12-09 | 柳州佳力电机股份有限公司 | Self-excited excitation system for large and medium-sized high-voltage generators |
| CN105099308A (en) * | 2015-09-22 | 2015-11-25 | 东方电机控制设备有限公司 | Generator excitation device |
| CN105099308B (en) * | 2015-09-22 | 2018-06-29 | 东方电机控制设备有限公司 | A kind of generator excitation unit |
| CN114094897A (en) * | 2020-07-31 | 2022-02-25 | 华为技术有限公司 | Radio excitation system, detection method and electric automobile |
| CN114172420A (en) * | 2021-11-26 | 2022-03-11 | 苏州热工研究院有限公司 | Rotor coupling double-machine parallel motor generator set complete set and protection control system |
| CN114172420B (en) * | 2021-11-26 | 2023-06-23 | 苏州热工研究院有限公司 | Complete set and protection control system of rotor coupling double-machine parallel motor generator set |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104038124B (en) | 2017-07-07 |
| WO2015184697A1 (en) | 2015-12-10 |
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