CN104242346B - A kind of LVRT Capability of Wind Turbine Generator control method - Google Patents
A kind of LVRT Capability of Wind Turbine Generator control method Download PDFInfo
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- CN104242346B CN104242346B CN201410489389.0A CN201410489389A CN104242346B CN 104242346 B CN104242346 B CN 104242346B CN 201410489389 A CN201410489389 A CN 201410489389A CN 104242346 B CN104242346 B CN 104242346B
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- 238000000034 method Methods 0.000 title claims abstract description 23
- 230000009194 climbing Effects 0.000 claims abstract description 12
- 230000001960 triggered effect Effects 0.000 claims description 4
- 208000000058 Anaplasia Diseases 0.000 claims description 3
- 238000010248 power generation Methods 0.000 abstract description 3
- 239000011295 pitch Substances 0.000 description 40
- 230000005611 electricity Effects 0.000 description 5
- 238000011084 recovery Methods 0.000 description 3
- 230000001133 acceleration Effects 0.000 description 2
- 241000208340 Araliaceae Species 0.000 description 1
- 208000033999 Device damage Diseases 0.000 description 1
- 235000005035 Panax pseudoginseng ssp. pseudoginseng Nutrition 0.000 description 1
- 235000003140 Panax quinquefolius Nutrition 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000011217 control strategy Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005672 electromagnetic field Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 235000008434 ginseng Nutrition 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000002633 protecting effect Effects 0.000 description 1
- 230000002459 sustained effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Classifications
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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
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/76—Power conversion electric or electronic aspects
Abstract
The present invention relates to a kind of LVRT Capability of Wind Turbine Generator control method, belong to technical field of wind power generation.The present invention is during low voltage crossing, judge whether generator speed and generator power all reach its corresponding setting value, if reached, pressure pitch control is then carried out to Wind turbines using given propeller pitch angle, and at the end of low-voltage state, by controlling generator torque set-point, making generator power, climbing rate is run according to the rules, carries out active recover.Control method of the present invention simplifies the rotor short-circuit device used during conventional low voltage crossing, reduce cost, control device is direct, there is master control directly to control pitch-controlled system, and then reduce wind speed round, ensure fan safe reliability service, control performance is good, by Wind turbines master control system directly control generator torque realize low voltage crossing during the stable of active power recover.
Description
Technical field
The present invention relates to a kind of LVRT Capability of Wind Turbine Generator control method, belong to technical field of wind power generation.
Background technology
Low voltage crossing Low voltage ride through (LVRT), refer in wind-driven generator grid entry point Voltage Drop
When, blower fan can keep grid-connected, or even provide certain reactive power to power network, power system restoration be supported, until power network is extensive
It is multiple normal, so that " passing through " this low-voltage time (region).
With wind-power electricity generation, proportion is increasing in electric power energy, and influence of the wind generator system to power network is
It can not ignore.The mode of access is concentrated on a large scale especially for China's wind-powered electricity generation, when grid collapses cause grid entry point voltage to fall
When falling, once the automatic off-grid of Wind turbines is likely to result in the collapse of line voltage and frequency, the safety and stability of power network is had a strong impact on
Operation, is restricted the application of this clean energy resource of wind-power electricity generation.Therefore, the Wind turbines of large-scale grid connection operation must have
There is low voltage ride-through capability (Low Voltage Ride Through, LVRT).
Low voltage crossing is still to keep the grid-connected specific operation of one kind when Voltage Drop occurs in power network to grid-connected blower fan
Functional requirement.During grid voltage sags, aerogenerator stator terminal voltage can be caused to decline, while stator overcurrent, so as to draw
Rise cause rotor-side overcurrent and overvoltage, if Voltage Drop than it is more serious when, it is also possible to cause converter electric electronic device
Damage.Rotor-side, which completes low voltage crossing, to reach that limitation passes through with bypass (releasing energy resistance) protection device of rotor loop
The electric current of exciter converter and the effect of rotor windings overvoltage, generator is maintained with this, and off-grid is not run.It is achieved that low
Voltage strategy uses hardware Crowbar circuit arrangements.But Crowbar circuit arrangements control circuit structure is complicated, circuit element
It is various, if circuit design is undesirable, easily cause switching device to damage.Some shortcomings in use are for example
Crowbar resistance makes greatly very much the too high influence safety of DC bus-bar voltage, and resistance is too small can not to resist fault current；If motor is transported
Scanning frequency degree is fast, and Voltage Drop depth is deeper, and fault current is bigger, and the poorer grade of Crowbar protecting effects is progressively exposed.
Publication No. 102412599A patent discloses a kind of dual feedback wind power generation system low voltage crossing Crowbar
Device absorbs protection circuit and exhausted including three-phase bridge uncontrollable rectifier bridge UR, sustained diode, high-power bleeder resistance R1, RCD
Edge grid bipolar transistor IGBT.The hardware circuit is complicated, circuit element is various, and makes control using device for power switching
Circuit processed is more complicated, if circuit design is undesirable, easily causes switching device to damage, such a solution can cause wind-powered electricity generation
Field ability out of hand in a short time.And how to design a kind of flexible, efficient method of control realize low voltage crossing into
For urgent need to solve the problem instantly.
The content of the invention
It is an object of the invention to provide a kind of LVRT Capability of Wind Turbine Generator control method, to solve current low voltage crossing
The control circuit of use is complicated, poor reliability and the problem of low efficiency.
The present invention provides a kind of LVRT Capability of Wind Turbine Generator control method, the controlling party to solve above-mentioned technical problem
Method comprises the following steps：
1) during Wind turbines are in low voltage crossing, collection generator speed and generator power, and judge whether
All reach its corresponding setting value；
If 2) reached, pressure pitch control is carried out to Wind turbines using given propeller pitch angle, until low voltage crossing
Terminate；
3) judge whether to receive the end signal of low-voltage state from current transformer, if it is, current from current transformer collection
Generator torque Torque_Ref_t2；
4) using current generator torque Torque_Ref_t2 as starting point, according to the climbing rate increase of setting, until generating electricity
Machine torque reaches the set-point of torque controller.
The step 2) in give propeller pitch angle for current propeller pitch angle add changing value, the changing value by put away the oars speed and
Put away the oars the time determination.
The step 4) in the climbing rate that sets as：
Wherein ramp_Tor_renew is that low-voltage recovers climbing rate, is provided by control parameter list, its default value is
10%.
The generator torque Torque_Ref_t2 is equal to Torque_Ref_t1* (UT/Unom), and wherein UT represents to fall
Period grid line voltage virtual value, Unom represents grid line voltage rated value, Torque_Ref_t1=Torque_Ref_t0,
The generator torque that Torque_Ref_t0 is collected when receiving low voltage signal for current transformer.
The generator torque Torque_Ref_t0 collected is not that the real generator collected from current transformer turns
Square, but the generator torque set-point after first-order low-pass ripple.
The step 2) in force pitch control in propeller pitch angle set-point provided by LVRT pitch controllers, LVRT pitches
When controller is triggered, current pitch angle value is recorded, on this basis, when forcing to become oar according to given change oar speed and change oar
Anaplasia oar.
The beneficial effects of the invention are as follows:The present invention judges generator speed and generator power during low voltage crossing
Its corresponding setting value whether is all reached, if reached, Wind turbines are carried out using given propeller pitch angle to force to become oar control
System, and at the end of low-voltage state, by controlling generator torque set-point, making generator power, climbing rate is transported according to the rules
OK, active recover is carried out.It is short that control method of the present invention simplifies the rotor used during conventional low voltage crossing
Road device, reduces cost, and control device directly, has master control directly to control pitch-controlled system, and then reduce wind speed round, it is ensured that wind
Machine safe and reliable operation, control performance is good, directly controls generator torque to realize that low-voltage is worn by Wind turbines master control system
The stable recovery of active power during more.
Brief description of the drawings
Fig. 1 is the pitch control flow chart of LVRT Capability of Wind Turbine Generator control process of the present invention；
Fig. 2 is the direct torque figure of LVRT Capability of Wind Turbine Generator control process of the present invention；
Fig. 3 is LVRT Capability of Wind Turbine Generator status of processes transition diagram of the present invention.
Embodiment
The embodiment to the present invention is further described below in conjunction with the accompanying drawings.
The present invention is during Wind turbines are in low voltage crossing, collection generator speed and generator power, and judges
Whether its corresponding setting value is all reached；If reached, pressure pitch control is carried out to Wind turbines using given propeller pitch angle,
Until low voltage crossing terminates；Judge whether to receive the end signal of low-voltage state from current transformer, if it is, from current transformer
The current generator torque Torque_Ref_t2 of collection；Using current generator torque Torque_Ref_t2 as starting point, according to
The climbing rate increase of setting, until generator torque reaches the set-point of torque controller, so as to complete wearing for whole low-voltage
More.Low voltage crossing control strategy of the present invention employed in above-mentioned control process includes low voltage crossing pitch control algorithm
With low voltage crossing generator torque control algolithm.
Low voltage crossing pitch control algorithm control flow employed in it is as shown in figure 1, in non-low voltage crossing shape
During state, control program uses pitch controller, exports propeller pitch angle set-point, this value is then passed into pitch position control again
Device, final output becomes oar speed preset value, and this value is directly handed down to variable pitch driver.When system monitoring to low voltage crossing becomes oar
Control signal is TRUE, i.e., when program needs to start change oar in advance, then the propeller pitch angle provided using LVRT pitch controllers is given
Value, instead of the value of Hub pitch controllers, as shown in Figure 2.When low voltage crossing process is near completion, it is no longer necessary to carry out change oar
During control, low voltage crossing control signal is FALSE, and pitch control is recovered to use original controller.
Pitch controller explanation for pitch control：The mentality of designing of Hub pitch controllers is, according to different generatings
Machine rotating speed and generator power, are controlled using PI, then provide change vane angle angle value, and LVRT pitch controllers become oar using pressure
Mode carry out change oar, as long as low voltage crossing pitch control signal be TRUE, program will not consider generator rotating speed and turn
Square, forces to put away the oars.The propeller pitch angle set-point that LVRT pitch controllers are provided becomes oar speed and becomes oar according to linear rule increase
Time, the two parameter lists were provided.When LVRT pitch controllers are triggered, program records current pitch angle value, basic herein
On, force to become oar according to anaplasia oar when given change oar speed and change oar.Become oar speed to put away the oars into maximum speed (8 degree/s)；Receive
The oar time：Generator acceleration is detected, the time of putting away the oars is obtained according to generator acceleration, maximum duration is 1S, by speed of putting away the oars
With the time of putting away the oars, can with the changing value to propeller pitch angle, wear after signal occurs, put away the oars 1s with 8 degree/s speed of putting away the oars, then low
The changing value for angle of putting away the oars is 8 degree.Changing value, as propeller pitch angle set-point are added on the basis of current propeller pitch angle.
Pitch control is required for during not every low voltage crossing, in some cases, it is not necessary to carry out becoming oar control
System.During low voltage crossing, the parameter such as rotating speed, the torque of program by checking generator, progress judges whether to need to carry out change oar
Whether control, i.e., trigger LVRT pitch controllers.
LVRT pitch controllers are triggered, control program is required to meet following two conditions.
1) generator speed needs to be more than or equal to gpr_feedForGenRpm, if trigger low voltage crossing,
Generator speed is not above this value, then program thinks that wind speed round is not high, it is not necessary to carry out shifting to an earlier date pitch control, abnormal
Normal award setting device control.
2) gpr_feedForGenPowPu times of generator power more than rated power.
Gpr_feedForGenPowPu is the value more than 0 less than 1.
Gpr_feedForGenRpm and gpr_feedForGenPowPu is two control parameters, is given by control parameter list
Go out.
Low voltage crossing generator torque control algolithm.Low-voltage state direct torque flow is as shown in Fig. 2 primary control program
Receive after low voltage signal, it is necessary first to collection Generator Status amount now, including generator speed, turn from current transformer
Square, and the rotating speed according to generator and torque, calculate generator power.This tittle is only gathered once.And a ginseng will be used as
Consider and remain behind, do not change with the change of low-voltage state.Active recovery and direct torque after low voltage crossing
It will all be performed according to this reference quantity, until low voltage crossing is completed, blower fan recovers normal operation.It should be noted that collecting
Generator torque be by the generator torque set-point after first-order low-pass ripple, rather than from current transformer collect it is true
Real generator torque, its reason is influenceed by low-voltage, and the true torque value that current transformer is provided may not be low-voltage
Generator torque before passing through.The generator speed collected, then be the process first-order low-pass ripple collected from encoder
Generator speed afterwards.
It is that when occurring low voltage crossing, electromagnetic field change is violent, very using a major reason of low-pass first order filter
Various electrical equipments may be interfered, on the one hand low pass filter can filter the noise signal of high frequency, on the other hand may be used
So that the signal collected will not because measuring apparatus by electromagnetic interference produce hop value and by very big interference.Now collect
Generator torque reference value record in variable Torque_Ref_t0, by calculating, the generator power reference value that draws note
Record is in variable Power_Ref_t0.
Low-voltage state terminates rear torque and recovers control algolithm.Primary control program receives low-voltage state from current transformer to be terminated
Signal after, start active to recover control, now major control generator torque set-point, so that generator power is according to rule
Fixed climbing rate operation.
In primary control program after current transformer receives the signal that low-voltage state terminates, primary control program is worked as from current transformer collection
Preceding generator torque Torque_Ref_t2.
There is grid line voltage during Torque_Ref_t2=Torque_Ref_t1* (UT/Unom), wherein UT represent to fall
Valid value, Torque_Ref_t1=Torque_Ref_t0, Unom represents grid line voltage rated value.According to current generator rotating speed
And torque value, the current power P ower_Ref_t2 of generator can be calculated.
For example：From 690V 138V (20% falls) is dropped into when line voltage is symmetrical, then Torque_Ref_t2=
Torque_Ref_t1* (138/690)=0.2*Torque_Ref_t1.
During active recovery, primary control program torque reference algorithm is：Using Torque_Ref_t2 as starting point, climbed according to certain
Ratio of slope increase, until generator torque reaches torque controller TorquePIController set-points.This climbing rate is：
It should be noted that ramp_Tor_renew, which is low-voltage, recovers climbing rate, provided by control parameter list, it is write from memory
It is 10% to recognize value.
Claims (6)
1. a kind of LVRT Capability of Wind Turbine Generator control method, it is characterised in that：The control method comprises the following steps：
1) during Wind turbines are in low voltage crossing, collection generator speed and generator power, and judge whether all to reach
To its corresponding setting value；
If 2) reached, pressure pitch control is carried out to Wind turbines using given propeller pitch angle, until low voltage crossing terminates；
If not up to, carrying out pitch control using Hub pitch control devices；
3) judge whether to receive the end signal of low-voltage state from current transformer, if it is, gathering current hair from current transformer
Motor torque Torque_Ref_t2；
4) using current generator torque Torque_Ref_t2 as starting point, according to the climbing rate increase of setting, until generator turns
Square reaches the set-point of torque controller.
2. LVRT Capability of Wind Turbine Generator control method according to claim 1, it is characterised in that：The step 2) in give
Fixed propeller pitch angle is that current propeller pitch angle adds changing value, and the changing value is determined by put away the oars speed and the time of putting away the oars.
3. LVRT Capability of Wind Turbine Generator control method according to claim 1, it is characterised in that：The step 4) in set
Fixed climbing rate is：
Wherein ramp_Tor_renew is that low-voltage recovers climbing rate, is provided by control parameter list, and its default value is 10%.
4. LVRT Capability of Wind Turbine Generator control method according to claim 3, it is characterised in that：The generator torque
Torque_Ref_t2 is equal to Torque_Ref_t1* (UT/Unom), and wherein UT represents to fall period grid line voltage virtual value,
Unom represents grid line voltage rated value, and Torque_Ref_t1=Torque_Ref_t0, Torque_Ref_t0 connects for current transformer
Receive the generator torque collected during low voltage signal.
5. LVRT Capability of Wind Turbine Generator control method according to claim 4, it is characterised in that：The hair collected
Motor torque Torque_Ref_t0 is not the real generator torque collected from current transformer, but passes through first-order low-pass
Generator torque set-point after ripple.
6. LVRT Capability of Wind Turbine Generator control method according to claim 1, it is characterised in that：The step 2) in it is strong
Propeller pitch angle set-point in pitch control processed is provided by LVRT pitch controllers, when LVRT pitch controllers are triggered, and record is current
Pitch angle value, on this basis, force become oar according to given change oar speed and become oar when anaplasia oar.
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| CN201410489389.0A CN104242346B (en) | 2014-09-19 | 2014-09-19 | A kind of LVRT Capability of Wind Turbine Generator control method |
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| CN201410489389.0A CN104242346B (en) | 2014-09-19 | 2014-09-19 | A kind of LVRT Capability of Wind Turbine Generator control method |
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Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106451543B (en) * | 2016-11-01 | 2018-11-23 | 清华大学 | A kind of flexible emulation mode of LVRT Capability of Wind Turbine Generator output characteristics |
| CN109995281B (en) * | 2017-12-30 | 2020-12-08 | 中国船舶重工集团海装风电股份有限公司 | Control method and device for fault recovery of wind turbine generator and readable storage medium |
| CN110474362B (en) * | 2019-07-11 | 2023-08-25 | 广东明阳龙源电力电子有限公司 | Low-voltage ride through control method and system for high-voltage high-capacity frequency converter |
| CN110336248B (en) * | 2019-08-19 | 2022-02-11 | 浙江继智自动化技术有限公司 | Intelligent safety type direct current brushless motor driver |
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| CN102646993A (en) * | 2012-04-25 | 2012-08-22 | 东方电气新能源设备（杭州）有限公司 | Low-voltage ride through (LVRT) system of wind generation set and method of the system |
| CN102709944A (en) * | 2012-05-24 | 2012-10-03 | 浙江运达风电股份有限公司 | Control method of low voltage through of wind driven generator set based on DGNR variable pitch system |
| CN103124079A (en) * | 2013-01-06 | 2013-05-29 | 中国电力科学研究院 | Coordinated control method for low voltage ride through of direct-drive permanent magnet wind turbine generator |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102646993A (en) * | 2012-04-25 | 2012-08-22 | 东方电气新能源设备（杭州）有限公司 | Low-voltage ride through (LVRT) system of wind generation set and method of the system |
| CN102709944A (en) * | 2012-05-24 | 2012-10-03 | 浙江运达风电股份有限公司 | Control method of low voltage through of wind driven generator set based on DGNR variable pitch system |
| CN103124079A (en) * | 2013-01-06 | 2013-05-29 | 中国电力科学研究院 | Coordinated control method for low voltage ride through of direct-drive permanent magnet wind turbine generator |
Non-Patent Citations (2)
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| 双馈型风力发电系统低电压穿越策略仿真;朱颖等;《电力自动化设备》;20100630;第30卷(第6期);第20-24页 * |
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