CN108134404B - Wind power generating set high voltage crossing control method and device - Google Patents
Wind power generating set high voltage crossing control method and device Download PDFInfo
- Publication number
- CN108134404B CN108134404B CN201711482150.0A CN201711482150A CN108134404B CN 108134404 B CN108134404 B CN 108134404B CN 201711482150 A CN201711482150 A CN 201711482150A CN 108134404 B CN108134404 B CN 108134404B
- Authority
- CN
- China
- Prior art keywords
- grid
- generating set
- wind generating
- high voltage
- connected point
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 37
- 230000001939 inductive effect Effects 0.000 claims abstract description 65
- 230000001965 increasing effect Effects 0.000 claims abstract description 41
- 238000012544 monitoring process Methods 0.000 claims abstract description 10
- 230000008859 change Effects 0.000 claims description 10
- 238000010586 diagram Methods 0.000 description 18
- 238000011084 recovery Methods 0.000 description 9
- 230000008569 process Effects 0.000 description 8
- 238000010248 power generation Methods 0.000 description 6
- 238000004088 simulation Methods 0.000 description 6
- 230000000630 rising effect Effects 0.000 description 4
- 230000001052 transient effect Effects 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000011217 control strategy Methods 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 238000007792 addition Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000005405 multipole Effects 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
Classifications
-
- H02J3/386—
-
- 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
- H02J3/24—Arrangements for preventing or reducing oscillations of power in networks
-
- 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
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/46—Controlling of the sharing of output between the generators, converters, or transformers
- H02J3/48—Controlling the sharing of the in-phase component
-
- 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
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/46—Controlling of the sharing of output between the generators, converters, or transformers
- H02J3/50—Controlling the sharing of the out-of-phase component
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Eletrric Generators (AREA)
Abstract
The embodiment of the invention discloses a kind of wind power generating set high voltage crossing control method and device.This method comprises: wind farm grid-connected voltage of real-time monitoring；According to the voltage rating that grid entry point voltage and wind power generating set export, control wind power generating set executes high voltage crossing and terminates high voltage crossing；Wherein, during executing high voltage crossing, control wind power generating set reduces the watt current provided to grid entry point, and increases the inductive reactive power electric current provided to grid entry point；After terminating high voltage crossing, control wind power generating set provides the watt current being gradually increased, and the working condition according to wind power generating set before executing high voltage crossing to grid entry point, and control wind power generating set provides reactive current to grid entry point.The wind power generating set high voltage crossing control method and device of the embodiment of the present invention can guarantee that network voltage restores, and can be avoided high voltage crossing failure.
Description
Technical Field
The invention relates to the technical field of wind power generation, in particular to a high voltage ride through control method and device for a wind generating set.
Background
The centralized access of large-scale wind turbines brings many new problems to the power system, wherein high voltage ride through capability is a very important item. The permanent magnet direct-drive fan adopts a variable-speed constant-frequency wind power generation technology of directly driving a multi-pole low-speed permanent magnet synchronous generator without a speed-up gear box and an impeller, the fan is connected to the grid through a full-power converter, the complete decoupling of the generator and a power grid is realized, and the grid connection characteristic of the fan mainly depends on the technical performance of the power grid side of the converter.
The high voltage ride through capability of the existing permanent magnet direct drive unit is mainly embodied in two aspects: 1) during the high voltage ride through period, active power balance is kept through the braking units connected in parallel with the direct current bus; 2) during high voltage ride through, the grid-side converter supports grid voltage recovery by outputting reactive current.
The existing control strategy for wind power generation is as follows: under the normal operation state, the variable flow controller provides reactive current for the power grid according to the instruction of a main controller of the wind generating set. When the power grid fails and high voltage ride through is executed, the instruction of the main controller is cut off, and the variable current controller directly sends reactive current to the power grid according to the rising degree of the terminal voltage of the wind generating set so as to help to recover the power grid voltage. When the fault is cleared, the reactive current output by the variable current controller changes to zero instantly.
Therefore, in the prior art, the wind farm participates in reactive/voltage regulation of the grid-connected point through reactive power output of the wind turbine generator, only transient reactive control during high voltage ride through is required, and no requirement is made on switching from transient to steady reactive control, so that the problem of high voltage ride through failure may occur in the actual operation process.
Disclosure of Invention
The embodiment of the invention provides a high voltage ride through control method and device for a wind generating set, which can reasonably control the reactive power provided by the wind generating set after the high voltage ride through is finished, ensure the voltage recovery of a power grid and avoid the failure of the high voltage ride through.
In one aspect, an embodiment of the present invention provides a high voltage ride through control method, where the method includes:
monitoring the voltage of a grid-connected point of a wind power plant in real time;
controlling the wind generating set to execute high voltage ride through and finish the high voltage ride through according to the voltage of the grid-connected point and the rated voltage output by the wind generating set; wherein,
controlling the wind generating set to reduce the active current provided to the grid-connected point and increase the inductive reactive current provided to the grid-connected point during the execution of the high voltage ride through;
and after finishing the high-voltage ride-through, controlling the wind generating set to provide gradually increased active current for the grid-connected point, and controlling the wind generating set to provide reactive current for the grid-connected point according to the working state of the wind generating set before the high-voltage ride-through is executed.
In one embodiment of the invention, the method for controlling the wind generating set to provide reactive current for the grid-connected point according to the working state of the wind generating set before the high-voltage crossing is executed comprises the following steps:
under the condition that the wind generating set provides zero reactive power to a grid-connected point before executing high voltage ride through, controlling the wind generating set to provide zero reactive current to the grid-connected point;
under the condition that the wind generating set provides capacitive reactive power to a grid-connected point before executing high voltage ride through, controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point;
under the condition that the wind generating set provides inductive reactive power to the grid-connected point before the high-voltage crossing is executed, the wind generating set is controlled to provide step change to an inductive reactive current value before the high-voltage crossing, or the wind generating set is controlled to provide gradually increased inductive reactive current to the grid-connected point.
In one embodiment of the invention, controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point comprises:
determining the increase rate of the capacitive reactive current according to the increase rate of the active power of the wind generating set and the power factor angle before the high voltage ride through;
and controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point according to the increase rate of the capacitive reactive current.
In one embodiment of the invention, increasing the inductive reactive current provided to the grid-connected point comprises:
determining inductive reactive current to be provided according to the grid-connected point voltage before the high voltage ride through, the grid-connected point voltage during the high voltage ride through, the rated current output by the wind generating set and the rated voltage;
the determined inductive reactive current is provided to a grid-tie point.
On the other hand, the embodiment of the invention provides a high voltage ride through control device of a wind generating set, which comprises:
the monitoring module is used for monitoring the grid-connected point voltage of the wind power plant in real time;
the first control module is used for controlling the wind generating set to execute high voltage ride through and finish the high voltage ride through according to the grid-connected point voltage and the rated voltage output by the wind generating set;
the second control module is used for controlling the wind generating set to reduce the active current provided for the grid-connected point and increase the inductive reactive current provided for the grid-connected point during the period of executing high voltage ride through;
and the third control module is used for controlling the wind generating set to provide gradually increased active current for the grid-connected point after the high-voltage ride-through is finished, and controlling the wind generating set to provide reactive current for the grid-connected point according to the working state of the wind generating set before the high-voltage ride-through is executed.
In one embodiment of the invention, the method for controlling the wind generating set to provide reactive current for the grid-connected point according to the working state of the wind generating set before the high-voltage crossing is executed comprises the following steps:
under the condition that the wind generating set provides zero reactive power to a grid-connected point before executing high voltage ride through, controlling the wind generating set to provide zero reactive current to the grid-connected point;
under the condition that the wind generating set provides capacitive reactive power to a grid-connected point before executing high voltage ride through, controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point;
under the condition that the wind generating set provides inductive reactive power to the grid-connected point before the high-voltage crossing is executed, the wind generating set is controlled to provide step change to an inductive reactive current value before the high-voltage crossing, or the wind generating set is controlled to provide gradually increased inductive reactive current to the grid-connected point.
In one embodiment of the invention, controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point comprises:
determining the increase rate of the capacitive reactive current according to the increase rate of the active power of the wind generating set and the power factor angle before the high voltage ride through;
and controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point according to the increase rate of the capacitive reactive current.
In one embodiment of the invention, increasing the inductive reactive current provided to the grid-connected point comprises:
determining inductive reactive current to be provided according to the grid-connected point voltage before the high voltage ride through, the grid-connected point voltage during the high voltage ride through, the rated current output by the wind generating set and the rated voltage;
the determined inductive reactive current is provided to a grid-tie point.
According to the high voltage ride through control method and device for the wind generating set, the wind generating set is controlled to provide reactive current for the grid-connected point according to the working state of the wind generating set before high voltage ride through is executed, reactive power provided by the wind generating set can be reasonably controlled after the high voltage ride through is finished, and the voltage recovery of a power grid is guaranteed. The embodiment of the invention performs transient reactive power control during high voltage ride through, and provides a detailed scheme for the reactive power control process of switching from transient state to steady state after the high voltage ride through is finished, so that high voltage ride through failure can be avoided.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments of the present invention will be briefly described below, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic flow chart of a high voltage ride through control method for a wind turbine generator system according to an embodiment of the invention;
FIG. 2 is a schematic diagram illustrating changes of active current and reactive current of a wind generating set under zero reactive power before high voltage ride through according to an embodiment of the present invention;
FIG. 3 is a schematic diagram illustrating a first variation of an active current and a reactive current of a wind turbine generator system under a condition of capacitive reactive power before high voltage ride through according to an embodiment of the present invention;
FIG. 4 is a schematic diagram illustrating a second variation of the active current and the reactive current of the wind turbine generator system in the case of the capacitive reactive power before the high voltage ride through according to the embodiment of the present invention;
FIG. 5 is a schematic diagram illustrating a first variation of active current and reactive current of a wind turbine generator system under the condition of inductive reactive power before high voltage ride through according to an embodiment of the present invention;
FIG. 6 is a schematic diagram illustrating a second variation of active current and reactive current of a wind turbine generator system under the condition of inductive reactive power before high voltage ride through according to an embodiment of the present invention;
FIG. 7 is a simulation diagram of zero reactive power generation of a wind generating set before high voltage ride through according to an embodiment of the present invention;
FIG. 8 is a simulation diagram of 500Kvar capacitive reactive power before a high voltage ride through of a wind turbine generator system according to an embodiment of the present invention;
FIG. 9 is a schematic simulation diagram of a wind turbine generator system with inductive reactive power of 500Kvar before high voltage ride through according to an embodiment of the present invention;
fig. 10 shows a schematic structural diagram of a high voltage ride through control device of a wind generating set according to an embodiment of the present invention.
Detailed Description
Features and exemplary embodiments of various aspects of the present invention will be described in detail below, and in order to make objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not to be construed as limiting the invention. It will be apparent to one skilled in the art that the present invention may be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
Fig. 1 shows a flow chart of a high voltage ride through control method of a wind generating set according to an embodiment of the invention. The wind generating set high voltage ride through control method can comprise the following steps:
s101: and monitoring the voltage of a grid-connected point of the wind power plant in real time.
S102: and controlling the wind generating set to execute high voltage ride through and finish the high voltage ride through according to the voltage of the grid-connected point and the rated voltage output by the wind generating set. Wherein, during the high voltage ride through of the wind generating set, S103 is executed, and after the wind generating set finishes the high voltage ride through, S104 is executed.
S103: and controlling the wind generating set to reduce the active current provided to the grid-connected point and increase the inductive reactive current provided to the grid-connected point.
S104: and controlling the wind generating set to provide gradually increased active current to the grid-connected point, and controlling the wind generating set to provide reactive current to the grid-connected point according to the working state of the wind generating set before the high-voltage crossing is executed.
Illustratively, the wind power plant grid-connected point voltage is monitored in real time, a positive sequence component of the voltage is extracted from the monitored grid-connected point voltage, and if the extracted positive sequence component of the voltage is greater than 1.1 times of rated voltage output by a wind generating set and lasts for 40 milliseconds (ms), the wind generating set is controlled to perform high voltage ride through.
Controlling the wind generating set to reduce the active current provided to the grid-connected point and increase the inductive reactive current provided to the grid-connected point during the high voltage ride through; and extracting a positive sequence component of the voltage from the grid-connected point voltage obtained in the high voltage ride through period, and determining whether the wind generating set finishes the high voltage ride through according to the currently extracted positive sequence component of the voltage and the rated voltage output by the wind generating set.
For example, assuming that the extracted positive sequence component of the grid-connected point voltage during the high voltage ride through is less than 1.1 times the rated voltage of the wind turbine generator system output and lasts for 50ms, the wind turbine generator system is controlled to end the high voltage ride through.
And after the high-voltage ride-through is finished, controlling the wind generating set to provide gradually increased active current for the grid-connected point, and controlling the wind generating set to provide reactive current for the grid-connected point according to the working state of the wind generating set before the high-voltage ride-through is executed.
In the prior art, a control strategy for wind power generation is that when a high voltage ride through fault is cleared, a reactive current output by a variable current controller of a wind generating set instantaneously changes to zero, and the working state of the wind generating set before the high voltage ride through occurs is not considered. This solution, which the inventors have found in long-term engineering practice, has the following drawbacks.
If the wind generating set generates inductive reactive power before the high voltage ride through, the reactive power is excessive after the high voltage ride through is finished, which is not beneficial to the voltage recovery of the power grid. In addition, after the high voltage ride through is finished, the active power is recovered rapidly, and at this time, if the wind generating set variable current controller does not send out inductive reactive power in time, the grid voltage will be increased, which may cause the wind generating set to execute secondary high voltage ride through, and may cause failure of the high voltage ride through.
If the wind generating set generates capacitive reactive power before the high voltage ride through, the reactive power is insufficient after the high voltage ride through is finished, and the recovery of the voltage of the power grid is not facilitated. In addition, after the high voltage ride through is finished, the active power is recovered rapidly, and at the moment, if the variable current controller does not send out the capacitive reactive power in time, the voltage of the power grid is reduced, so that the wind generating set can execute the low voltage ride through to cause the failure of the high voltage ride through.
Therefore, the embodiments of the present invention provide the following solutions after finishing the high voltage ride through based on the operating state of the wind turbine generator set before performing the high voltage ride through.
The first scheme is as follows: and controlling the wind generating set to provide zero reactive current to the grid-connected point under the condition that the wind generating set provides zero reactive power to the grid-connected point before the high-voltage ride-through is executed.
Scheme II: and in the case that the wind generating set provides the capacitive reactive power to the grid-connected point before the high voltage ride-through is executed, controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point.
The third scheme is as follows: and under the condition that the wind generating set provides inductive reactive power to the grid-connected point before the high voltage ride-through is executed, controlling the wind generating set to provide gradually increased inductive reactive current to the grid-connected point.
And the scheme is as follows: and under the condition that the wind generating set provides inductive reactive power to the grid-connected point before the high-voltage crossing is executed, controlling the wind generating set to provide step change to an inductive reactive current value before the high-voltage crossing.
Corresponding to the first scheme, fig. 2 shows a schematic diagram of changes of active current and reactive current of the wind generating set provided by the embodiment of the invention under the condition of generating zero reactive power before high voltage ride through.
At the time t1, high voltage ride through is started to be executed, and the wind generating set provides inductive reactive current for the grid-connected point so as to reduce the voltage of the grid-connected point; at the time t2, the high voltage ride through is finished, the reactive current changes to zero instantly, the reactive power returns to zero, and the active power starts to return; at the time t3, the active current is recovered to the active current before the high voltage ride through, at this time, the active power is recovered to the active power before the high voltage ride through, and the power grid operates stably.
Corresponding to the second scheme, fig. 3 shows a first schematic diagram of changes of an active current and a reactive current of a wind generating set provided by the embodiment of the invention in the case of generating capacitive reactive power before high voltage ride through; fig. 4 shows a schematic diagram of a second variation of the active current and the reactive current of the wind turbine generator system in the case of the capacitive reactive power before the high voltage ride through according to the embodiment of the present invention.
In fig. 3, at time t1, the high voltage ride through is started, and the wind generating set provides an inductive reactive current to the grid-connected point to reduce the voltage of the grid-connected point; at the time t2, the high voltage ride through is finished, the reactive current changes to zero instantly, the reactive power is zero, and the reactive current and the active current start to recover; at time t3, the active current is restored to the active current before the high voltage ride through, the reactive current is restored to the reactive current before the high voltage ride through, at this time, the active power is restored to the active power before the high voltage ride through, and the reactive power is restored to the capacitive reactive power before the high voltage ride through. And (5) stably operating the power grid.
In fig. 4, at time t1, the high voltage ride through is started, and the wind turbine generator system supplies an inductive reactive current to the grid-connected point to reduce the voltage of the grid-connected point; at the time t2, the high voltage ride through is finished, the reactive current does not change to zero instantly, and the reactive current and the active current start to recover, namely the reactive power and the active power start to recover; at time t3, the active current is restored to the active current before the high voltage ride through, the reactive current is restored to the reactive current before the high voltage ride through, at this time, the active power is restored to the active power before the high voltage ride through, and the reactive power is restored to the capacitive reactive power before the high voltage ride through. And (5) stably operating the power grid.
In one embodiment of the present invention, the reactive current value may be set when the high voltage ride through is ended and the reactive current does not change to zero instantaneously, for example, when the high voltage ride through is ended, the reactive current changes toWherein Ip is the active current during the high voltage ride through,is the power factor angle before high voltage ride through.
In one embodiment of the present invention, controlling the wind turbine generator system to provide gradually increasing capacitive reactive current to the grid-connected point may include: determining the increase rate of the capacitive reactive current according to the increase rate of the active power of the wind generating set and the power factor angle before the high voltage ride through; and controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point according to the increase rate of the capacitive reactive current.
For example, assuming that the active power of the wind turbine generator set increases at a rate of Pn per second and the power factor angle before the high voltage ride through isDetermining the recovery rate of the reactive power asEvery second. And Pn is the rated power of the wind generating set. Determining the increase rate of the capacitive reactive current according to the determined reactive power recovery rate; and controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point according to the increase rate of the capacitive reactive current.
In one embodiment of the invention, the rate of increase of active power of the wind park may be set between 30% Pn per second and 10Pn per second, corresponding to a rate of increase of reactive power betweenPer second toBetween each second.
Corresponding to the third scheme, fig. 5 shows a first variation schematic diagram of the active current and the reactive current of the wind generating set provided by the embodiment of the invention under the condition of generating inductive reactive power before high voltage ride through.
At the time t1, high voltage ride through is started to be executed, and the wind generating set provides inductive reactive current for the grid-connected point so as to reduce the voltage of the grid-connected point; at the time t2, the high voltage ride through is finished, the reactive current instantaneously changes to zero, the reactive power is zero, and the reactive current and the active current start to recover, namely the reactive power and the active power start to recover; at the time t3, the active current is restored to the active current before the high voltage ride through, the reactive current is restored to the inductive reactive current before the high voltage ride through, at this time, the active power is restored to the active power before the high voltage ride through, and the reactive power is restored to the inductive reactive power before the high voltage ride through. And (5) stably operating the power grid.
Corresponding to the fourth solution, fig. 6 shows a second schematic diagram of changes of active current and reactive current of the wind generating set provided by the embodiment of the present invention in the case of generating inductive reactive power before high voltage ride through.
At the time t1, high voltage ride through is started to be executed, and the wind generating set provides inductive reactive current for the grid-connected point so as to reduce the voltage of the grid-connected point; at the time t2, when the high voltage ride-through is finished, the active current starts to recover, namely the active power starts to recover, and the reactive current provided by the wind generating set to the grid-connected point is instantaneously stepped to the inductive reactive current value before the high voltage ride-through; at time t3, the active current is restored to the active current before the high voltage ride through, and at this time, the active power is restored to the active power before the high voltage ride through. And (5) stably operating the power grid.
The reason why the reactive current step changes at time t2 will be described.
The wind generating set can send reactive power while sending active power, and the reactive power can cause the voltage of a grid-connected point to be reduced; the more active power that is sent, the more inductive reactive power that is created and the more voltage drops that are created.
If the wind generating set generates inductive reactive power before the high voltage ride through, after the high voltage ride through is finished, if the active power of the wind generating set is recovered according to the slope, if the reactive power starts from zero, the inductive reactive power is lacked, and therefore the voltage of a grid connection point is increased.
Thus, in the example of fig. 6, the reactive current step changes to the pre-high voltage ride through value at time t2, and the lack of inductive reactive power in the system is made up to prevent the wind park from entering the high voltage ride through condition again.
In one embodiment of the present invention, increasing the inductive reactive current provided to the grid-connected point may include: determining inductive reactive current to be provided according to the grid-connected point voltage before the high voltage ride through, the grid-connected point voltage during the high voltage ride through, the rated current output by the wind generating set and the rated voltage; the determined inductive reactive current is provided to a grid-tie point.
The reactive current Ir is calculated from the voltage change during the high voltage ride through by the following expression (1).
K is a reactive current compensation coefficient, U0 is a positive sequence component of the grid-connected point voltage before the high voltage ride through, U1 is a positive sequence component of the grid-connected point voltage during the high voltage ride through, In is the rated current output by the wind generating set, and Un is the rated voltage output by the wind generating set.
And determining the reactive current Iq required to be provided for the grid-connected point according to the calculated reactive current Ir and the positive sequence component I0 of the reactive current of the grid-connected point before the high voltage passes through.
In one embodiment of the invention, when determining the reactive current Iq required to be provided to the grid-connected point, the reactive current Iq takes the minimum value of I0+ Ir and Ir.
According to the high voltage ride through control method of the wind generating set, the wind generating set is controlled to provide reactive current for the grid-connected point according to the working state of the wind generating set before high voltage ride through is executed, the reactive power provided by the wind generating set can be reasonably controlled after the high voltage ride through is finished, the voltage recovery of a power grid is ensured, and the failure of the high voltage ride through can be avoided.
In an embodiment of the present invention, the wind turbine generator system high voltage ride through control method according to the embodiment of the present invention may further include: during the high voltage ride through execution period, determining whether overtime faults occur when the wind generating set executes the high voltage ride through according to the grid-connected point voltage, the grid-connected point voltage rising amplitude and preset time corresponding to the grid-connected point voltage rising amplitude during the high voltage ride through execution period; and if the overtime fault of the high voltage ride through executed by the wind generating set is determined, outputting alarm information of the overtime fault of the high voltage ride through.
For example, assume that the grid-connected point voltage drop amplitude corresponds to a preset duration, as shown in table 1.
TABLE 1
| Grid point voltage rising amplitude (pu) | Preset duration (millisecond) |
| 1.15 | 10000 |
| 1.2 | 2000 |
| 1.25 | 1000 |
| 1.3 | 500 |
For example, assuming that the extracted positive sequence component of the grid-connected point voltage during the high voltage ride through is a rated voltage which is 1.2 times, that is, a per unit value is 1.2, and the duration is 2000 milliseconds, determining that the wind generating set has an overtime fault when performing the high voltage ride through; at the moment, alarm information of overtime faults of high voltage ride through is output.
Fig. 7 shows a simulation diagram of zero reactive power generation of a wind generating set before high voltage ride through according to an embodiment of the present invention.
As can be seen from fig. 7, during the high voltage ride through, the reactive current takes precedence, and the remaining capacity current generates the active current in its entirety. It should be noted that the reactive current per unit value and the positive sequence reactive power shown in fig. 7 are the actual reactive current per unit value and the actual positive sequence reactive power inverted value, respectively.
Fig. 8 shows a simulation diagram of 300 kvm capacitive reactive power before a high voltage ride through of a wind turbine generator system provided by the embodiment of the invention.
As can be seen from fig. 8, during the high voltage ride through, the reactive current is preferred, and the residual capacity current generates active current completely; during the high-voltage ride-through period, if the minimum value of I0+ Ir and Ir is not more than-1 pu, the reactive current Iq is-1 pu, and if the minimum value of I0+ Ir and Ir is more than-1 pu, the reactive current Iq is the minimum value of I0+ Ir and Ir; reactive current is sent to-1 pu; after the high voltage ride through is finished, the reactive power is rapidly recovered to 300 kilovolts (kvar). It should be noted that the reactive current per unit value and the positive sequence reactive power shown in fig. 9 are the actual reactive current per unit value and the actual positive sequence reactive power inverted value, respectively.
Fig. 9 shows a simulation schematic diagram of 300 kilovolt inductive reactive power before a high voltage ride through of a wind generating set provided by the embodiment of the invention.
As can be seen from fig. 9, during the high voltage ride through, the reactive current is preferred, and the residual capacity current generates active current completely; during the high voltage ride through, because the reactive current I0 is negative before the high voltage ride through, the I0+ Ir is less than Ir at the moment, if the I0+ Ir is less than-1 pu, the reactive current Iq takes-1 pu, if the I0+ Ir is not less than-1 pu, the reactive current Iq takes I0+ Ir, and the reactive current is sent to-1 pu; after the high voltage ride through is finished, the reactive power is quickly recovered to-500 kvar. It should be noted that the reactive current per unit value and the positive sequence reactive power shown in fig. 9 are the actual reactive current per unit value and the actual positive sequence reactive power inverted value, respectively.
The wind generating set high voltage ride through control method provided by the embodiment of the invention can also determine whether overtime fault occurs when the wind generating set executes high voltage ride through, and can output alarm information of the overtime fault of the high voltage ride through when the overtime fault occurs, so that a user can maintain the wind generating set according to the alarm information.
Corresponding to the method embodiment, the embodiment of the invention also provides a high voltage ride through control device of the wind generating set.
Fig. 10 shows a schematic structural diagram of a high voltage ride through control device of a wind generating set according to an embodiment of the present invention. The wind generating set high voltage ride through control device can include:
and the monitoring module 101 is used for monitoring the grid-connected point voltage of the wind power plant in real time.
And the first control module 102 is used for controlling the wind generating set to execute high voltage ride through and finish the high voltage ride through according to the grid-connected point voltage and the rated voltage output by the wind generating set.
And the second control module 103 is used for controlling the wind generating set to reduce the active current provided to the grid-connected point and increase the inductive reactive current provided to the grid-connected point during the period of executing the high voltage ride through.
And the third control module 104 is used for controlling the wind generating set to provide gradually increased active current to the grid-connected point after the high-voltage ride-through is finished, and controlling the wind generating set to provide reactive current to the grid-connected point according to the working state of the wind generating set before the high-voltage ride-through is executed.
In one embodiment of the invention, the method for controlling the wind generating set to provide reactive current for the grid-connected point according to the working state of the wind generating set before the high-voltage crossing is executed comprises the following steps:
under the condition that the wind generating set provides zero reactive power to a grid-connected point before executing high voltage ride through, controlling the wind generating set to provide zero reactive current to the grid-connected point;
under the condition that the wind generating set provides capacitive reactive power to a grid-connected point before executing high voltage ride through, controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point;
under the condition that the wind generating set provides inductive reactive power to the grid-connected point before the high-voltage crossing is executed, the wind generating set is controlled to provide step change to an inductive reactive current value before the high-voltage crossing, or the wind generating set is controlled to provide gradually increased inductive reactive current to the grid-connected point.
In one embodiment of the invention, controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point comprises:
determining the increase rate of the capacitive reactive current according to the increase rate of the active power of the wind generating set and the power factor angle before the high voltage ride through;
and controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point according to the increase rate of the capacitive reactive current.
In one embodiment of the invention, increasing the inductive reactive current provided to the grid-connected point comprises:
determining inductive reactive current to be provided according to the grid-connected point voltage before the high voltage ride through, the grid-connected point voltage during the high voltage ride through, the rated current output by the wind generating set and the rated voltage;
the determined inductive reactive current is provided to a grid-tie point.
In an embodiment of the present invention, the wind turbine generator system high voltage ride through control device of the embodiment of the present invention may further include:
and the determining module is used for determining whether the wind generating set has overtime fault when the wind generating set executes the high voltage ride through according to the grid-connected point voltage, the grid-connected point voltage boosting amplitude and the preset time length corresponding to the grid-connected point voltage boosting amplitude during the high voltage ride through.
And the output module is used for outputting alarm information of the overtime fault of the high voltage ride through if the overtime fault of the high voltage ride through executed by the wind generating set is determined.
According to the high-voltage ride-through control device provided by the embodiment of the invention, the wind generating set is controlled to provide the reactive current for the grid-connected point according to the working state of the wind generating set before the high-voltage ride-through is executed, so that the reactive power provided by the wind generating set can be reasonably controlled after the high-voltage ride-through is finished, the voltage recovery of a power grid is ensured, and the failure of the high-voltage ride-through can be avoided. And whether the wind generating set breaks down when carrying out the high voltage ride through can be determined, and when breaking down, the alarm information of the high voltage ride through fault can be output, so that a user can maintain the wind generating set according to the alarm information.
It is to be understood that the invention is not limited to the specific arrangements and instrumentality described above and shown in the drawings. A detailed description of known methods is omitted herein for the sake of brevity. In the above embodiments, several specific steps are described and shown as examples. However, the method processes of the present invention are not limited to the specific steps described and illustrated, and those skilled in the art can make various changes, modifications and additions or change the order between the steps after comprehending the spirit of the present invention.
It should also be noted that the exemplary embodiments mentioned in this patent describe some methods or systems based on a series of steps or devices. However, the present invention is not limited to the order of the above-described steps, that is, the steps may be performed in the order mentioned in the embodiments, may be performed in an order different from the order in the embodiments, or may be performed simultaneously.
As described above, only the specific embodiments of the present invention are provided, and it can be clearly understood by those skilled in the art that, for convenience and brevity of description, the specific working processes of the system, the module and the unit described above may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again. It should be understood that the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the present invention, and these modifications or substitutions should be covered within the scope of the present invention.
Claims (4)
1. A wind generating set high voltage ride through control method is characterized by comprising the following steps:
monitoring the voltage of a grid-connected point of a wind power plant in real time;
controlling the wind generating set to perform high voltage ride through and finish the high voltage ride through according to the grid-connected point voltage and the rated voltage output by the wind generating set; wherein,
controlling the wind generating set to reduce the active current provided to the grid-connected point and increase the inductive reactive current provided to the grid-connected point during the execution of the high voltage ride through;
after finishing the high-voltage ride-through, controlling the wind generating set to provide gradually increased active current for the grid-connected point, and controlling the wind generating set to provide reactive current for the grid-connected point according to the working state of the wind generating set before the high-voltage ride-through is executed; wherein,
the increasing the inductive reactive current provided to the grid-connected point includes:
determining inductive reactive current required to be provided according to the grid-connected point voltage before the high voltage ride through, the grid-connected point voltage during the high voltage ride through, the rated current output by the wind generating set and the rated voltage; providing the determined inductive reactive current to the grid-connection point;
the controlling the wind generating set to provide reactive current to a grid-connected point according to the working state of the wind generating set before the high-voltage crossing is executed comprises the following steps:
controlling the wind generating set to provide zero reactive current to the grid-connected point in case the wind generating set provides zero reactive power to the grid-connected point before performing the high voltage ride through;
controlling the wind turbine generator set to provide a gradually increasing capacitive reactive current to the grid-connected point in case the wind turbine generator set provides capacitive reactive power to the grid-connected point before performing the high voltage ride-through;
and under the condition that the wind generating set provides inductive reactive power to the grid-connected point before the high-voltage crossing is executed, controlling the wind generating set to provide step change to an inductive reactive current value before the high-voltage crossing, or controlling the wind generating set to provide gradually increased inductive reactive current to the grid-connected point.
2. The method of claim 1, wherein the controlling the wind turbine generator set to provide gradually increasing capacitive reactive current to the point of grid connection comprises:
determining the increase rate of the capacitive reactive current according to the increase rate of the active power of the wind generating set and a power factor angle before high voltage ride through;
and controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point according to the increase rate of the capacitive reactive current.
3. A wind generating set high voltage ride through control device, characterized in that the device includes:
the monitoring module is used for monitoring the grid-connected point voltage of the wind power plant in real time;
the first control module is used for controlling the wind generating set to perform high voltage ride through and finish the high voltage ride through according to the grid-connected point voltage and the rated voltage output by the wind generating set;
the second control module is used for controlling the wind generating set to reduce the active current provided for the grid-connected point and increase the inductive reactive current provided for the grid-connected point during the period of executing high voltage ride through;
the third control module is used for controlling the wind generating set to provide gradually increased active current for the grid-connected point after the high-voltage ride-through is finished, and controlling the wind generating set to provide reactive current for the grid-connected point according to the working state of the wind generating set before the high-voltage ride-through is executed; wherein,
the increasing the inductive reactive current provided to the grid-connected point includes:
determining inductive reactive current required to be provided according to the grid-connected point voltage before the high voltage ride through, the grid-connected point voltage during the high voltage ride through, the rated current output by the wind generating set and the rated voltage; providing the determined inductive reactive current to the grid-connection point;
the controlling the wind generating set to provide reactive current to a grid-connected point according to the working state of the wind generating set before the high-voltage crossing is executed comprises the following steps:
controlling the wind generating set to provide zero reactive current to the grid-connected point in case the wind generating set provides zero reactive power to the grid-connected point before performing the high voltage ride through;
controlling the wind turbine generator set to provide a gradually increasing capacitive reactive current to the grid-connected point in case the wind turbine generator set provides capacitive reactive power to the grid-connected point before performing the high voltage ride-through;
and under the condition that the wind generating set provides inductive reactive power to the grid-connected point before the high-voltage crossing is executed, controlling the wind generating set to provide step change to an inductive reactive current value before the high-voltage crossing, or controlling the wind generating set to provide gradually increased inductive reactive current to the grid-connected point.
4. The apparatus of claim 3, wherein the controlling the wind turbine generator system to provide gradually increasing capacitive reactive current to the point of connection comprises:
determining the increase rate of the capacitive reactive current according to the increase rate of the active power of the wind generating set and a power factor angle before high voltage ride through;
and controlling the wind generating set to provide gradually increased capacitive reactive current to the grid-connected point according to the increase rate of the capacitive reactive current.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711482150.0A CN108134404B (en) | 2017-12-29 | 2017-12-29 | Wind power generating set high voltage crossing control method and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711482150.0A CN108134404B (en) | 2017-12-29 | 2017-12-29 | Wind power generating set high voltage crossing control method and device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108134404A CN108134404A (en) | 2018-06-08 |
| CN108134404B true CN108134404B (en) | 2019-11-22 |
Family
ID=62394041
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711482150.0A Active CN108134404B (en) | 2017-12-29 | 2017-12-29 | Wind power generating set high voltage crossing control method and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108134404B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110165705B (en) * | 2019-05-30 | 2020-10-27 | 湖南大学 | High-voltage ride through control method and system for offshore double-fed wind turbine generator |
| CN112994074B (en) * | 2019-12-13 | 2022-07-26 | 新疆金风科技股份有限公司 | Low-high voltage continuous ride through control method and system for permanent magnet direct-drive wind generating set |
| CN112968464B (en) * | 2019-12-13 | 2022-12-09 | 新疆金风科技股份有限公司 | High-low voltage continuous ride-through control method and system for permanent magnet direct-drive wind generating set |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102801181A (en) * | 2012-07-25 | 2012-11-28 | 山东电力集团公司烟台供电公司 | Power coordination control method based on direct-drive wind-turbine-generator wind farm |
| CN105633997A (en) * | 2014-11-04 | 2016-06-01 | 国家电网公司 | Wind generating set voltage crossing control method and device |
| CN106921177A (en) * | 2017-04-19 | 2017-07-04 | 北京金风科创风电设备有限公司 | Low voltage ride through control method and device of wind generating set and simulation system |
-
2017
- 2017-12-29 CN CN201711482150.0A patent/CN108134404B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102801181A (en) * | 2012-07-25 | 2012-11-28 | 山东电力集团公司烟台供电公司 | Power coordination control method based on direct-drive wind-turbine-generator wind farm |
| CN105633997A (en) * | 2014-11-04 | 2016-06-01 | 国家电网公司 | Wind generating set voltage crossing control method and device |
| CN106921177A (en) * | 2017-04-19 | 2017-07-04 | 北京金风科创风电设备有限公司 | Low voltage ride through control method and device of wind generating set and simulation system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108134404A (en) | 2018-06-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108336761B (en) | Power control method, device and system for wind power plant and computer equipment | |
| Ye et al. | Revolution of frequency regulation in the converter-dominated power system | |
| CN108155665B (en) | Low voltage ride through control method and device for wind generating set | |
| Muyeen et al. | Reduction of frequency fluctuation for wind farm connected power systems by an adaptive artificial neural network controlled energy capacitor system | |
| CN103730906B (en) | A kind of control method for coordinating suppressing Hybrid HVDC commutation failure | |
| RU2010143316A (en) | WIND POWER PLANT WITH ASYNCHRONOUS DUAL POWER SUPPLY MACHINE AND METHOD OF OPERATION OF SUCH WIND POWER PLANT | |
| CN104283207B (en) | Zero-boost starting method for accessing wind power plant to flexible direct-current power transmission system | |
| CN108134404B (en) | Wind power generating set high voltage crossing control method and device | |
| WO2017118175A1 (en) | Emergency control method applicable to wind-photovoltaic power station | |
| CN107425542B (en) | The control method of DFIG reactive power compensation in low voltage failure crossing process | |
| Tu et al. | The synthetic inertia controller for MMC-HVDC based offshore wind farm integration | |
| Nanjun et al. | A frequency deadband-based virtual inertia control for grid-connected power converters | |
| CN112994074B (en) | Low-high voltage continuous ride through control method and system for permanent magnet direct-drive wind generating set | |
| CN110838724B (en) | Control method and system for preventing wind power plant from operating in isolated island mode | |
| Ye et al. | Black start scheme formation considering dynamic wind power penetration limit | |
| Yao et al. | Coordinated frequency support and wind turbine preset restoration scheme of VSC-mtdc integrated offshore wind farms | |
| CN112968464B (en) | High-low voltage continuous ride-through control method and system for permanent magnet direct-drive wind generating set | |
| Liu et al. | Overview of advanced control technology for wind power generation | |
| Liu et al. | Frequency regulation of VSC-MTDC system with offshore wind farms | |
| CN113507132B (en) | Method and system for alleviating optimization of direct current restarting control parameters | |
| CN104617598A (en) | Wind power plant low voltage riding through method based on dynamic direct current leakage resistor | |
| Guoqing et al. | Study on Operation Characteristics of Wind Power Grid-connected Doubly-Fed AC/DC Hybrid System | |
| CN114362224B (en) | Frequency control method and device for battery energy storage system | |
| Xu et al. | Dynamic modeling and simulation of distributed static compensators in system impact studies | |
| Soliman et al. | A fault ride through strategy for wind energy conversion system based on permanent magnet synchronous generator |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |