CN108181588A - Offshore wind farm engineering is electrically activated load test method - Google Patents
Offshore wind farm engineering is electrically activated load test method Download PDFInfo
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- CN108181588A CN108181588A CN201810172656.XA CN201810172656A CN108181588A CN 108181588 A CN108181588 A CN 108181588A CN 201810172656 A CN201810172656 A CN 201810172656A CN 108181588 A CN108181588 A CN 108181588A
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- current transformer
- power
- wind
- load test
- electrically activated
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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
- G01R31/34—Testing dynamo-electric machines
Abstract
The invention discloses a kind of offshore wind farm engineering by the method for electrically activating load test.At present, the technical issues of how at sea booster stations do load test, are those skilled in the art's urgent need to resolve during being electrically activated.The present invention is latched unit side converter, power grid side converter is as reactive-load compensator, the reactive power for sending out or absorbing according to experiment demand adjustment current transformer when wind power generating set is in safe shutdown state；By controlling the power of every current transformer and putting into the quantity of current transformer; and then flexibly control the amplitude of output current; meet offshore boosting station by the requirement for electrically activating experiment, realize a whole set of verification of primary equipment, secondary circuit, measuring instrument, protective relays and automation equipments.The present invention realizes offshore boosting station before wind power generation set grid-connection and is electrically activated load test, and perfect offshore wind farm engineering is electrically activated content of the test, is reduced the risk of later stage set grid-connection experiment, is improved debugging quality, shorten the test run duration.
Description
Technical field
It is specifically a kind of based on the current transformer reactive-load compensation method of operation the present invention relates to Oversea wind power generation field
Offshore wind farm engineering is electrically activated load test method.
Background technology
With the continuous development of new energy technology, Oversea wind power generation engineering is gradually risen.At sea booster stations by
The stage electrically activated requires according to power engineering firing test, by load test to primary equipment, secondary circuit, metering
Instrument, protective relays and automation equipments carry out a whole set of verification, this experiment has the amplitude of load current certain requirement.
Offshore boosting station is indicated that part test run work is started by electrically activating.It calculates and actual measurement proves, in electricity consumption most
What experiment available power can not much meet offshore boosting station under big load condition is electrically activated load test requirement.And wind-force
Generator changes motor running mode since paddle adjustment angle is uncontrollable, and wind turbine hypervelocity is easily caused under high wind conditions even
Driving seriously damages unit.In addition, installation capacitor as load scheme by sea haulage time and cargo ship condition,
The lifting condition of offshore platform, the installation space of offshore boosting station and temporary cable arrangement, the weight of interim capacitor and sea
The access voltage class of load capacity calculating, interim capacitor at stage+module and the factors such as selection interval and electrical capacity calculating
It influences, often lacks execution condition.
For marine wind electric field often after multimachine is grid-connected, load current carries out offshore boosting station when meeting test requirements document at present
Load test.This method can not determine the reliability of equipment before wind turbine is grid-connected, will generate following many adverse effects：
1st, the construction speed at wind energy project sea is influenced by many factors such as sea situation, weather, stormy waves.If assembling platform
Number and submarine cable operation do not have wind turbine load carrying condition or current wind can not meet minimum work(needed for load test
Rate requirement, it is necessary to postpone the offshore boosting station load test time, so as to influence the reliability service of station electricity consumption, need to put into for a long time
Diesel-driven generator increases cost as power supply for construction.
2nd, the grid-connected preceding load test of wind-driven generator is not done, will cause interconnection route protection, offshore boosting station busbar,
The main protection of main transformer and reactor protection is out of service, and the interim single set longtime running of protection, primary equipment is exposed to relaying configuration
And in the state of insufficiency, there are hidden troubles during operation.
3rd, it can not ensure the integrality and correctness of secondary loop of mutual inductor.
4th, the monitoring system configuration of wind turbine, debugging efforts are the operations after wind turbine is grid-connected, in fan monitoring system information not
It is grid-connected to wind turbine progress in the case of complete, if occurring abnormal conditions simultaneously, troubleshooting area will be increased, extends Failure elimination
Time.
Therefore, how at sea booster stations do load test during being electrically activated, and are that there is an urgent need for solutions by those skilled in the art
Certainly the technical issues of.
Invention content
The technical problems to be solved by the invention are to overcome the problems of the above-mentioned prior art, are provided a kind of based on unsteady flow
The offshore wind farm engineering of the device reactive-load compensation method of operation is electrically activated load test method, is operated with simplifying, and improves safety,
It avoids increasing additional testing equipment.
To achieve the above object, the present invention adopts the following technical scheme that：Offshore wind farm engineering is electrically activated on-load examination
Proved recipe method using the current transformer of wind-driven generator installed in marine wind electric field, provides offshore boosting station and is electrically activated on-load
Load current needed for experiment；
During wind power generating set normal operation, generator-side converter and power grid side converter are in unlocked state, different
Step and the active power of straight drive blower flow to power grid from generator side by current transformer, and current transformer does not exchange idle work(with power grid
Rate；The active power of double-fed wind turbine flows directly into power grid from generator unit stator side, and rotor-side exchanges one by current transformer with power grid
Part active power is sent with absorbing the working condition depending on double-fed wind turbine, and current transformer does not exchange reactive power with power grid；
When wind power generating set is in load test state, engine block is stopped transport, generator-side converter locking, electricity
Net side current transformer unlocks, and generator unit stator must be isolated with power grid for double-fed wind turbine；By the control for changing power grid side converter
Parameter processed makes it be operated in the reactive-load compensation method of operation；By changing reactive current or reactive power set-point, every change is controlled
The reactive power that stream device is absorbed or sent out；
The capacity of size of current and each wind driven generator set converter according to needed for load test, when experiment, are flexible
The reactive power that every current transformer of number of units and control of selection input current transformer sends out or receives.
The present invention is opened using the wind driven generator set converter reactive-load compensation method of operation to carry out offshore wind farm engineering by electricity
Dynamic load test；By controlling the power of every current transformer and putting into the quantity of current transformer, and then flexibly control output current
Amplitude, meet offshore boosting station by the requirement for electrically activating experiment, realize that primary equipment, secondary circuit, measuring instrument, relay are protected
The a whole set of verification of shield and automation equipment.
Offshore wind farm engineering is in order to increase capacity and efficiency at present, generally using following three kinds of wind power generating sets：
1) double-fed wind turbine, there is gear-box, and generator uses wire-wound asynchronous motor, part is accessed between rotor and power grid
Power AC-DC-AC converter.
2) straight drive blower, non-gear box, generator use synchronous motor, and total power is accessed between stator and power grid and is handed over directly
Alternating flow device.
3) asynchronous wind turbine, there is gear-box, and generator uses squirrel cage asynchronous motor, full work(is accessed between stator and power grid
Rate AC-DC-AC converter.
This three kinds of units realize the control of engine block using generator-side converter, are realized using power grid side converter
Constant frequency exports.Wherein net side current transformer uses active and reactive decoupling control policy, sets power outer shroud and current inner loop.Usually
For simplify control logic, for active ring using DC voltage mode is determined, idle ring, which uses, determines reactive current or reactive power side
Formula, it is active and reactive individually controllable.Therefore power grid side converter, theoretically can be with isolated operation, by changing reactive current or nothing
The set-point of work(power into the reactive-load compensation method of operation, realizes pure idle input or output.Above-mentioned three kinds generally use
The current transformer grid side part of wind power generating set all has the function of this.
As the supplement of above-mentioned technical proposal, include the following steps：
1) AC system operating status and wind power generating set primary connection are changed, determines the interim protection of input, Zhi Houtong
Cross external power supply preheating current transformer, using collect wire pair current transformer and wind turbine boosting become charging；
2) after current transformer and wind turbine boosting become charging complete, check whether converter control system state is normal；
If converter control system state is normal condition, control model on the spot is switched to, and in in-place activation net
Side converter is idle to mould-fixed manually, then forces wind power generating set net side energy storing of switch, closes wind-force hair after the completion
Motor networking side switchs, and net side current transformer exchange side has pressure at this time, starts net side current transformer on the spot, checks that current transformer is currently practical
Whether output is zero；
3) the currently practical output of such as current transformer is zero, the amplitude limit of open reactive current set-point, according to experiment demand every
Idle reference value, the set-point of each current transformer of inspection and the reactive power of reality output are inputted on the current transformer of platform input experiment
It is whether consistent；
4) set-point of such as each current transformer is consistent with the reactive power of reality output, to primary equipment, secondary circuit, meter
Measure instrument, protective relays and automation equipments carry out a whole set of verification.
As the supplement of above-mentioned technical proposal, after the completion of the whole series verification, each current transformer of reduction is idle to be output to 0, stops transport
Net side current transformer, current transformer control parameter are restored to normal operating condition, disconnect wind power generating set net side switch, recovery system
The method of operation.
As the supplement of above-mentioned technical proposal, in step 2), if converter control system state is abnormal condition, switching
Current transformer is to normal operation mode.
As the supplement of above-mentioned technical proposal, in step 3), if the currently practical output of current transformer is not zero, modification configuration,
It is zero to make the currently practical output of current transformer.
As the supplement of above-mentioned technical proposal, in step 4), the set-point of such as each current transformer and reality output it is idle
Power is inconsistent, modification configuration, and the set-point for making each current transformer is consistent with the reactive power of reality output.
The invention has the advantages that：The present invention is without additional equipment, merely with wind power generating set in itself
Current transformer realizes the adjusting of test load, and controllability is strong, easy to operate, clear process, and reliability is high.The present invention is in wind-power electricity generation
Offshore boosting station is realized before set grid-connection and is electrically activated load test, perfect offshore wind farm engineering is electrically activated in experiment
Hold, reduce the risk of later stage set grid-connection experiment, improve debugging quality, shorten the test run duration.
Description of the drawings
Fig. 1 is that (Fig. 1 a are Wind turbines unsteady flow to the wind driven generator set converter schematic diagram that uses of the embodiment of the present invention
Device structure chart, Fig. 1 b are net side current transformer control strategy figure)；
In Fig. 1 a, LfFor inductance element, ifFor alternating current, UOFor alternating voltage, CfFor capacity cell, iinvBecome for net side
Flow device alternating current；
In Fig. 1 b；UdcFor DC voltage；igdFor electric current direct-axis component；igqFor electric current quadrature axis component；UsFor network voltage；
ugcdFor modulation voltage direct-axis component；ugcqFor modulation voltage quadrature axis component；θgFor alternating voltage phase angle；ua、ub、ucFor exchange three
Phase voltage；ω is angular rate, and Lg is equivalent inductance；Upper right corner Dai " ﹡ in above-mentioned symbol " represent the set-point of this electrical quantity；
Fig. 2 is retouched for offshore wind farm engineering provided in an embodiment of the present invention by the Fit Models for electrically activating load test method
State figure (Fig. 2 a are normal operating condition figure, and Fig. 2 b are load test state diagram)；
Fig. 3 is offshore wind farm engineering provided in an embodiment of the present invention by the flow chart for electrically activating load test method；
Fig. 4 is electrically activated load test method application implementation illustration for offshore wind farm engineering provided in an embodiment of the present invention
It is intended to.
Specific embodiment
Below in conjunction with specification drawings and specific embodiments, further illustrate the present invention.
Offshore wind farm engineering as shown in Figure 3 is electrically activated load test method, and its step are as follows：
1) after on-test, AC system operating status and wind power generating set primary connection are changed, determines that input is interim
Protection, later by external power supply preheat current transformer, using collect wire pair current transformer and wind turbine boosting become charging；Current transformer and wind
After machine boosting becomes charging complete, check whether converter control system state is normal.If needed in experiment using double-fed unit,
It needs stator and power grid isolation.
2) such as converter control system state is normal condition, is switched to control model on the spot, and in in-place activation
Net side current transformer is idle to mould-fixed manually, then forces wind power generating set net side energy storing of switch, closes the wind-force after the completion
Generating set net side switchs, and net side current transformer exchange side has pressure at this time, starts net side current transformer on the spot, checks that current transformer is currently real
Whether border output is zero；If converter control system state is abnormal condition, switch current transformer to normal operation mode.
3) the currently practical output of such as current transformer is zero, the amplitude limit of open reactive current set-point, according to experiment demand every
Idle reference value, the set-point of each current transformer of inspection and the reactive power of reality output are inputted on the current transformer of platform input experiment
It is whether consistent；If the currently practical output of current transformer is not zero, modification configuration, it is zero to make the currently practical output of current transformer.
4) set-point of such as each current transformer is consistent with the reactive power of reality output, to primary equipment, secondary circuit, meter
Measure instrument, protective relays and automation equipments carry out a whole set of verification；As each current transformer set-point and reality output it is idle
Power is inconsistent, modification configuration, and the set-point for making each current transformer is consistent with the reactive power of reality output.
5) after the completion of a whole set of verification, each current transformer of reduction is idle to be output to 0, and stoppage in transit net side current transformer, current transformer controls
Parameter reconstruction disconnects wind power generating set net side switch, the recovery system method of operation is complete by electric test to normal operating condition
Into.
The present invention realizes the tune of test load merely with the current transformer of wind power generating set in itself without additional equipment
Section, controllability is strong, easy to operate, clear process, and reliability is high.From the point of view of the offshore wind farm engineering construction example described in attached drawing 4,
The routine of 220kV offshore boosting stations is configured, only need to put into several current transformers can meet verification demand, personnel, equipment into
This well below other schemes, has extremely strong engineering practice advantage.
The above is merely illustrative of the technical solution of the present invention and unrestricted, and those of ordinary skill in the art are to this hair
The other modifications or equivalent replacement that bright technical solution is made, without departing from the spirit and scope of technical solution of the present invention,
It is intended to be within the scope of the claims of the invention.
Claims (6)
1. offshore wind farm engineering is electrically activated load test method, which is characterized in that
Using the current transformer of wind-driven generator installed in marine wind electric field, offshore boosting station is provided and is electrically activated load test institute
The load current needed；
During wind power generating set normal operation, generator-side converter and power grid side converter are in unlocked state, it is asynchronous and
The active power of straight drive blower flows to power grid from generator side by current transformer, and current transformer does not exchange reactive power with power grid；It is double
The active power of feedback wind turbine flows directly into power grid from generator unit stator side, and rotor-side exchanges a part by current transformer with power grid to be had
Work(power is sent with absorbing the working condition depending on double-fed wind turbine, and current transformer does not exchange reactive power with power grid；
When wind power generating set is in load test state, engine block is stopped transport, generator-side converter locking, grid side
Current transformer unlocks, and generator unit stator must be isolated with power grid for double-fed wind turbine；Joined by the control for changing power grid side converter
Number, makes it be operated in the reactive-load compensation method of operation；By changing reactive current or reactive power set-point, every current transformer is controlled
The reactive power for absorbing or sending out；
The capacity of size of current and each wind driven generator set converter according to needed for load test, when experiment, flexibly select
Put into the reactive power that every current transformer of number of units and control of current transformer sends out or receives.
2. offshore wind farm engineering according to claim 1 is electrically activated load test method, which is characterized in that including such as
Lower step：
1) AC system operating status and wind power generating set primary connection are changed, the interim protection of input is determined, later by outer
Connect power supply preheating current transformer, using collect wire pair current transformer and wind turbine boosting become charging；
2) after current transformer and wind turbine boosting become charging complete, check whether converter control system state is normal；
If converter control system state is normal condition, control model on the spot is switched to, and become in in-place activation net side
It is idle to mould-fixed manually to flow device, then forces wind power generating set net side energy storing of switch, closes the wind-driven generator after the completion
Networking side switchs, and net side current transformer exchange side has pressure at this time, starts net side current transformer on the spot, checks the currently practical output of current transformer
Whether it is zero；
3) the currently practical output of such as current transformer is zero, the amplitude limit of open reactive current set-point, according to experiment demand in every throwing
Enter and idle reference value inputted on the current transformer of experiment, check each current transformer set-point and reality output reactive power whether
Unanimously；
4) set-point of such as each current transformer is consistent with the reactive power of reality output, to primary equipment, secondary circuit, gauge
Table, protective relays and automation equipments carry out a whole set of verification.
3. offshore wind farm engineering according to claim 2 is electrically activated load test method, which is characterized in that a whole set of school
After the completion of testing, each current transformer of reduction is idle to be output to 0, and stoppage in transit net side current transformer, current transformer control parameter is restored to normal fortune
Row state disconnects wind power generating set net side switch, the recovery system method of operation.
4. the offshore wind farm engineering according to Claims 2 or 3 is electrically activated load test method, which is characterized in that
In step 2), if converter control system state is abnormal condition, switch current transformer to normal operation mode.
5. the offshore wind farm engineering according to Claims 2 or 3 is electrically activated load test method, which is characterized in that
In step 3), if the currently practical output of current transformer is not zero, modification configuration, it is zero to make the currently practical output of current transformer.
6. the offshore wind farm engineering according to Claims 2 or 3 is electrically activated load test method, which is characterized in that
In step 4), such as set-point of each current transformer and the reactive power of reality output are inconsistent, and modification configuration makes each change
The set-point for flowing device is consistent with the reactive power of reality output.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109103940A (en) * | 2018-10-19 | 2018-12-28 | 上海电气风电集团有限公司 | A kind of marine wind electric field on-load falls the method for power transmission |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130277988A1 (en) * | 2012-04-20 | 2013-10-24 | Hyoung Jin JI | Two-way releasable mortise structure |
| CN104836248A (en) * | 2015-05-20 | 2015-08-12 | 沈阳工业大学 | Hybrid energy storage system suitable for wind turbine generator set, and control method |
| CN204721000U (en) * | 2015-01-11 | 2015-10-21 | 北京清能世福科技有限公司 | A kind of friendly and expand grid-connected power generation system flexibly to electrical network |
| CN105140938A (en) * | 2015-08-05 | 2015-12-09 | 东南大学 | Energy-storage system-based self-starting control method for double-fed induction generator |
| CN105790305A (en) * | 2016-04-20 | 2016-07-20 | 清华大学 | Offshore wind power grid connection system based on full-bridge MMC DC-side serial connection and control method thereof |
| CN105914794A (en) * | 2016-05-17 | 2016-08-31 | 东南大学 | STATCOM/BESS-based wind turbine group coordinated self-starting control method |
| CN106611960A (en) * | 2015-10-27 | 2017-05-03 | 中国电力科学研究院 | High-voltage ride-through method for double-fed wind turbine generator set |
| CN107482653A (en) * | 2017-09-28 | 2017-12-15 | 曲阜师范大学 | The direct current transportation Double-feed wind power power of the assembling unit fluctuates and fault control system and method |
| CN107579540A (en) * | 2017-08-18 | 2018-01-12 | 河海大学 | A kind of marine wind electric field resultant fault traversing method grid-connected based on HVAC |
-
2018
- 2018-03-01 CN CN201810172656.XA patent/CN108181588B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130277988A1 (en) * | 2012-04-20 | 2013-10-24 | Hyoung Jin JI | Two-way releasable mortise structure |
| CN204721000U (en) * | 2015-01-11 | 2015-10-21 | 北京清能世福科技有限公司 | A kind of friendly and expand grid-connected power generation system flexibly to electrical network |
| CN104836248A (en) * | 2015-05-20 | 2015-08-12 | 沈阳工业大学 | Hybrid energy storage system suitable for wind turbine generator set, and control method |
| CN105140938A (en) * | 2015-08-05 | 2015-12-09 | 东南大学 | Energy-storage system-based self-starting control method for double-fed induction generator |
| CN106611960A (en) * | 2015-10-27 | 2017-05-03 | 中国电力科学研究院 | High-voltage ride-through method for double-fed wind turbine generator set |
| CN105790305A (en) * | 2016-04-20 | 2016-07-20 | 清华大学 | Offshore wind power grid connection system based on full-bridge MMC DC-side serial connection and control method thereof |
| CN105914794A (en) * | 2016-05-17 | 2016-08-31 | 东南大学 | STATCOM/BESS-based wind turbine group coordinated self-starting control method |
| CN107579540A (en) * | 2017-08-18 | 2018-01-12 | 河海大学 | A kind of marine wind electric field resultant fault traversing method grid-connected based on HVAC |
| CN107482653A (en) * | 2017-09-28 | 2017-12-15 | 曲阜师范大学 | The direct current transportation Double-feed wind power power of the assembling unit fluctuates and fault control system and method |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109103940A (en) * | 2018-10-19 | 2018-12-28 | 上海电气风电集团有限公司 | A kind of marine wind electric field on-load falls the method for power transmission |
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