阅读说明：本技术 一种风力发电机防共振控制方法及装置 (Anti-resonance control method and device for wind driven generator ) 是由 张为民 周一晨 于 2019-10-24 设计创作，主要内容包括：本发明公开了一种风力发电机防共振控制方法及装置,所述方法包括：当风力发电机的转速增加至共振带对应的转速下限值且风力发电机的输出功率大于等于预设的第一功率参考值时,控制风力发电机的输出功率在第一预设时间范围内减小至预设的第二功率参考值；当风力发电机的转速减小至共振带对应的转速上限值且风力发电机的输出功率大于等于预设的第三功率参考值时,控制风力发电机的输出功率在第二预设时间范围内增大至预设的第四功率参考值。本发明的优点在于：通过对风力发电机转速及输出功率的控制,促使风力发电机快速通过共振带,避免产生共振现象。(The invention discloses an anti-resonance control method and device for a wind driven generator, wherein the method comprises the following steps: when the rotating speed of the wind driven generator is increased to a rotating speed lower limit value corresponding to a resonance band and the output power of the wind driven generator is greater than or equal to a preset first power reference value, controlling the output power of the wind driven generator to be reduced to a preset second power reference value within a first preset time range; and when the rotating speed of the wind driven generator is reduced to the rotating speed upper limit value corresponding to the resonance band and the output power of the wind driven generator is greater than or equal to a preset third power reference value, controlling the output power of the wind driven generator to be increased to a preset fourth power reference value within a second preset time range. The invention has the advantages that: the wind driven generator is prompted to rapidly pass through a resonance band by controlling the rotating speed and the output power of the wind driven generator, and the resonance phenomenon is avoided.)

1. An anti-resonance control method for a wind driven generator, the method comprising: when the rotating speed of the wind driven generator is increased to a rotating speed lower limit value corresponding to a resonance band and the output power of the wind driven generator is greater than or equal to a preset first power reference value, controlling the output power of the wind driven generator to be reduced to a preset second power reference value within a first preset time range, so that the rotating speed of the wind driven generator is equal to or greater than a rotating speed upper limit value corresponding to the resonance band;

and when the rotating speed of the wind driven generator is reduced to the rotating speed upper limit value corresponding to the resonance band and the output power of the wind driven generator is greater than or equal to the preset third power reference value, controlling the output power of the wind driven generator to be increased to the preset fourth power reference value within a second preset time range, so that the rotating speed of the wind driven generator is smaller than or equal to the rotating speed lower limit value corresponding to the resonance band.

2. The anti-resonance control method for the wind driven generator according to claim 1, further comprising the step of controlling the rotation speed of the wind driven generator to be stabilized at the rotation speed lower limit value corresponding to the resonance band when the rotation speed of the wind driven generator is increased to the rotation speed lower limit value corresponding to the resonance band.

3. The anti-resonance control method for the wind driven generator according to claim 1, wherein the step of controlling the output power of the wind driven generator to be reversely adjusted before the output power of the wind driven generator is reduced to the preset second power reference value within the first preset time range further comprises the step of reversely adjusting the output power of the wind driven generator, and the step of reversely adjusting comprises:

controlling the rotating speed of the wind driven generator to be stabilized at a rotating speed lower limit value corresponding to a resonance band;

canceling the control of the rotating speed of the wind driven generator until the output power of the wind driven generator is greater than or equal to a preset fifth power reference value and is stable within a third preset time range;

the preset fifth power reference value is greater than the preset first power reference value, and the preset first power reference value is greater than the preset second power reference value.

4. The anti-resonance control method for wind turbine generator according to claim 3, wherein the predetermined second power reference value is 0.

5. The anti-resonance control method for the wind driven generator according to claim 1, further comprising the step of controlling the rotation speed of the wind driven generator to be stabilized at the upper limit value of the rotation speed corresponding to the resonance band when the rotation speed of the wind driven generator is reduced to the upper limit value of the rotation speed corresponding to the resonance band.

6. The anti-resonance control method for the wind driven generator according to claim 1, wherein before the output power of the wind driven generator is increased to the preset fourth power reference value within the second preset time range, the method further comprises the step of performing reverse regulation on the output power of the wind driven generator, and the step of performing reverse regulation comprises:

controlling the rotating speed of the wind driven generator to be stabilized at a rotating speed upper limit value corresponding to a resonance band;

canceling the control of the rotating speed of the wind driven generator until the output power of the wind driven generator is less than or equal to a preset sixth power reference value and is stable within a fourth preset time range;

the preset fourth power reference value is greater than the preset third power reference value, and the preset third power reference value is greater than the preset sixth power reference value.

7. The anti-resonance control method for the wind driven generator according to any one of claims 1 to 6, wherein when the rotating speed of the wind driven generator reaches the upper limit value or the lower limit value of the rotating speed corresponding to the resonance band, the output power of the wind driven generator is controlled to operate according to a preset maximum power curve.

8. An anti-resonance control device of a wind driven generator is characterized by comprising a forward direction crossing resonance band module and a reverse direction crossing resonance band module;

the forward direction passing through resonance band module comprises a first rotation speed detection unit, a first power detection unit, a first comparison unit and a first power control unit,

the first rotating speed detection unit is used for detecting the rotating speed of the wind driven generator;

the first power detection unit is used for detecting the output power of the wind driven generator;

the first comparison unit is used for comparing whether the rotating speed of the wind driven generator is increased to a rotating speed lower limit value corresponding to a resonance band or not and comparing whether the output power of the wind driven generator is greater than or equal to a preset first power reference value or not;

the first power control unit is used for controlling the output power of the wind driven generator to be reduced to a preset second power reference value within a first preset time range when the first comparison unit compares that the rotating speed of the wind driven generator is increased to a rotating speed lower limit value corresponding to a resonance band and the output power of the wind driven generator is greater than or equal to a preset first power reference value, so that the rotating speed of the wind driven generator is equal to or greater than the rotating speed upper limit value corresponding to the resonance band;

the reverse crossing resonance band module comprises a second rotating speed detection unit, a second power detection unit, a second comparison unit and a second power control unit, wherein,

the second rotating speed detection unit is used for detecting the rotating speed of the wind driven generator;

the second power detection unit is used for detecting the output power of the wind driven generator;

the second comparison unit is used for comparing whether the rotating speed of the wind driven generator is reduced to a rotating speed upper limit value corresponding to a resonance band or not and comparing whether the output power of the wind driven generator is larger than or equal to a preset third power reference value or not;

and the second power control unit is used for controlling the output power of the wind driven generator to be increased to a preset fourth power reference value within a second preset time range when the second comparison unit compares that the rotating speed of the wind driven generator is reduced to the rotating speed upper limit value corresponding to the resonance band and the output power of the wind driven generator is greater than or equal to a preset third power reference value, so that the rotating speed of the wind driven generator is smaller than or equal to the rotating speed lower limit value corresponding to the resonance band.

9. The anti-resonance control device for the wind driven generator according to claim 8, wherein the forward direction crossing resonance band module further comprises a first stabilizing unit, and the first stabilizing unit is configured to control the rotation speed of the wind driven generator to be stabilized at the lower limit value of the rotation speed corresponding to the resonance band when the rotation speed of the wind driven generator is increased to the lower limit value of the rotation speed corresponding to the resonance band.

10. The anti-resonance control device for wind power generator according to claim 8, wherein the forward-direction crossing resonance band module further comprises a first reverse adjusting unit for performing reverse adjustment on the output power of the wind power generator, the first reverse adjusting unit comprises:

the rotating speed lower limit value limiting stator unit is used for controlling the rotating speed of the wind driven generator to be stabilized at a rotating speed lower limit value corresponding to a resonance band before the output power of the wind driven generator is reduced to a preset second power reference value within a first preset time range;

the first speed control subunit is used for canceling the control on the rotating speed of the wind driven generator when the output power of the wind driven generator is greater than or equal to a preset fifth power reference value and is stable within a third preset time range;

the preset fifth power reference value is greater than the preset first power reference value, and the preset first power reference value is greater than the preset second power reference value.

11. The anti-resonance control device for wind turbine according to claim 10, wherein the predetermined second power reference value is 0.

12. The anti-resonance control device for the wind driven generator according to claim 8, wherein the reverse crossing resonance band module further comprises a second stabilizing unit, and the second stabilizing unit is configured to control the rotation speed of the wind driven generator to be stabilized at the upper limit value of the rotation speed corresponding to the resonance band when the rotation speed of the wind driven generator is reduced to the upper limit value of the rotation speed corresponding to the resonance band.

13. The anti-resonance control device for the wind driven generator according to claim 8, wherein the reverse crossing resonance band module further comprises a second reverse adjusting unit, the second reverse adjusting unit performs reverse adjustment on the output power of the wind driven generator, and the second reverse adjusting unit comprises:

the rotating speed upper limit value limiting stator unit is used for controlling the rotating speed of the wind driven generator to be stabilized at a rotating speed upper limit value corresponding to a resonance band before the output power of the wind driven generator is increased to a preset fourth power reference value within a second preset time range;

the second rotating speed control subunit is used for canceling the control of the rotating speed of the wind driven generator when the output power of the wind driven generator is less than or equal to a preset sixth power reference value and is stable within a fourth preset time range;

the preset fourth power reference value is greater than the preset third power reference value, and the preset third power reference value is greater than the preset sixth power reference value.

14. The anti-resonance control device for the wind driven generator according to any one of claims 8 to 13, further comprising a maximum power tracking module, wherein the maximum power tracking module is configured to control the output power of the wind driven generator to operate according to a preset maximum power curve when the rotation speed of the wind driven generator reaches an upper limit value or a lower limit value of the rotation speed corresponding to the resonance band.

Technical Field

The invention relates to wind power generation, in particular to an anti-resonance control method and device for a wind driven generator.

Background

Wind power generation is a process of converting wind energy into mechanical energy and then converting the mechanical energy into electrical energy. In the operation process of the wind driven generator, the rotation frequency of the rotor of the wind driven generator is easy to be close to the natural frequency of a structural component (such as the first-order natural frequency of a tower) to generate resonance, the resonance band has a wide frequency range, and if the operation rotating speed falls within the rotating speed interval corresponding to the resonance band, the whole wind driven generator can vibrate strongly after lasting for tens of seconds or even seconds, the performance of a unit is influenced, the structural component is damaged, and serious economic loss is caused.

At present, when the wind speed is higher than the rated wind speed, the wind speed is controlled by adopting a constant rotating speed, and the rotating speed is the rated rotating speed, so that resonance is not easy to occur. However, when the wind speed is below the rated wind speed, the maximum power tracking control method is adopted, and the rotating speed is adjusted in proportion to the wind speed so as to maintain the optimal tip speed ratio unchanged, thereby obtaining more wind energy and providing more power generation. However, since the rotation speed varies with the variation of the wind speed, the rotation speed is likely to fall within the rotation speed interval corresponding to the resonance band, thereby causing resonance. In recent years, the wind turbine generator has been designed to have a larger size, and the weight of the wind turbine generator has been increased and the natural frequency has been decreased, and the larger the size of the wind turbine generator has been, the lower the operating speed has been, and therefore, the higher the probability that the natural frequency of the structural member such as the tower will resonate with the rotational frequency of the wind turbine generator during the operation of the wind turbine generator.

Therefore, in the operation process of the wind turbine, when the rotation speed value of the wind turbine reaches a value near the rotation speed value corresponding to the resonance band, how to rapidly traverse the resonance band is an urgent problem to be solved in the industry at present.

Disclosure of Invention

The invention aims to solve the technical problem that the wind driven generator in the prior art is easy to resonate when the rotating speed value of the wind driven generator reaches the vicinity of the rotating speed value corresponding to the resonance band in the operation process.

The invention solves the technical problems through the following technical scheme: an anti-resonance control method for a wind turbine, the method comprising: when the rotating speed of the wind driven generator is increased to a rotating speed lower limit value corresponding to a resonance band and the output power of the wind driven generator is greater than or equal to a preset first power reference value, controlling the output power of the wind driven generator to be reduced to a preset second power reference value within a first preset time range, so that the rotating speed of the wind driven generator is equal to or greater than a rotating speed upper limit value corresponding to the resonance band;

and when the rotating speed of the wind driven generator is reduced to the rotating speed upper limit value corresponding to the resonance band and the output power of the wind driven generator is greater than or equal to the preset third power reference value, controlling the output power of the wind driven generator to be increased to the preset fourth power reference value within a second preset time range, so that the rotating speed of the wind driven generator is smaller than or equal to the rotating speed lower limit value corresponding to the resonance band. Through the control of the rotating speed and the output power of the wind driven generator, the wind driven generator can be prompted to rapidly pass through a resonance band, the resonance phenomenon is avoided, the safety of the wind driven generator is improved, and the service life is prolonged.

Further, when the rotating speed of the wind driven generator is increased to the rotating speed lower limit value corresponding to the resonance band, the method further comprises the step of controlling the rotating speed of the wind driven generator to be stabilized at the rotating speed lower limit value corresponding to the resonance band.

Further, before the output power of the wind driven generator is controlled to be reduced to the preset second power reference value within the first preset time range, the method further comprises the step of performing reverse regulation on the output power of the wind driven generator, and the step of performing reverse regulation comprises the following steps:

controlling the rotating speed of the wind driven generator to be stabilized at a rotating speed lower limit value corresponding to a resonance band;

canceling the control of the rotating speed of the wind driven generator until the output power of the wind driven generator is greater than or equal to a preset fifth power reference value and is stable within a third preset time range;

the preset fifth power reference value is greater than the preset first power reference value, and the preset first power reference value is greater than the preset second power reference value.

As a further improvement of the above technical solution, the preset second power reference value is 0.

Further, the method further comprises the step of controlling the rotating speed of the wind driven generator to be stabilized at the rotating speed upper limit value corresponding to the resonance band when the rotating speed of the wind driven generator is reduced to the rotating speed upper limit value corresponding to the resonance band.

Further, before the output power of the wind driven generator is controlled to increase to the preset fourth power reference value within the second preset time range, the method further comprises a step of performing reverse regulation on the output power of the wind driven generator, and the step of performing reverse regulation comprises:

controlling the rotating speed of the wind driven generator to be stabilized at a rotating speed upper limit value corresponding to a resonance band;

canceling the control of the rotating speed of the wind driven generator until the output power of the wind driven generator is less than or equal to a preset sixth power reference value and is stable within a fourth preset time range;

the preset fourth power reference value is greater than the preset third power reference value, and the preset third power reference value is greater than the preset sixth power reference value.

Further, when the rotating speed of the wind driven generator reaches the rotating speed upper limit value or the rotating speed lower limit value corresponding to the resonance band, the output power of the wind driven generator is controlled to operate according to a preset maximum power curve.

The invention also provides an anti-resonance control device of the wind driven generator, which comprises a forward crossing resonance band module and a reverse crossing resonance band module,

the forward direction passing through resonance band module comprises a first rotation speed detection unit, a first power detection unit, a first comparison unit and a first power control unit,

the first rotating speed detection unit is used for detecting the rotating speed of the wind driven generator;

the first power detection unit is used for detecting the output power of the wind driven generator;

the first comparison unit is used for comparing whether the rotating speed of the wind driven generator is increased to a rotating speed lower limit value corresponding to a resonance band or not and comparing whether the output power of the wind driven generator is greater than or equal to a preset first power reference value or not;

when the first comparison unit compares that the rotating speed of the wind driven generator is increased to the rotating speed lower limit value corresponding to the resonance band and the output power of the wind driven generator is greater than or equal to the preset first power reference value, the first power control unit controls the output power of the wind driven generator to be reduced to the preset second power reference value within a first preset time range so that the rotating speed of the wind driven generator is equal to or greater than the rotating speed upper limit value corresponding to the resonance band;

the reverse crossing resonance band module comprises a second rotating speed detection unit, a second power detection unit, a second comparison unit and a second power control unit, wherein,

the second rotating speed detection unit is used for detecting the rotating speed of the wind driven generator;

the second power detection unit is used for detecting the output power of the wind driven generator;

the second comparison unit is used for comparing whether the rotating speed of the wind driven generator is reduced to a rotating speed upper limit value corresponding to a resonance band or not and comparing whether the output power of the wind driven generator is larger than or equal to a preset third power reference value or not;

and the second power control unit is used for controlling the output power of the wind driven generator to be increased to a preset fourth power reference value within a second preset time range when the second comparison unit compares that the rotating speed of the wind driven generator is reduced to the rotating speed upper limit value corresponding to the resonance band and the output power of the wind driven generator is greater than or equal to a preset third power reference value, so that the rotating speed of the wind driven generator is smaller than or equal to the rotating speed lower limit value corresponding to the resonance band.

Through the control of the rotating speed and the output power of the wind driven generator, the wind driven generator can be prompted to rapidly pass through a resonance band, the resonance phenomenon is avoided, the safety of the wind driven generator is improved, and the service life is prolonged.

Further, the forward crossing resonance band module further comprises a first stabilizing unit, and the first stabilizing unit is used for controlling the rotating speed of the wind driven generator to be stabilized at the rotating speed lower limit value corresponding to the resonance band when the rotating speed of the wind driven generator is increased to the rotating speed lower limit value corresponding to the resonance band.

Further, the forward-direction crossing resonance band module further comprises a first reverse adjustment unit, the first reverse adjustment unit is used for performing reverse adjustment on the output power of the wind driven generator, and the first reverse adjustment unit comprises:

the rotating speed lower limit value limiting stator unit is used for controlling the rotating speed of the wind driven generator to be stabilized at a rotating speed lower limit value corresponding to a resonance band before the output power of the wind driven generator is reduced to a preset second power reference value within a first preset time range;

the first speed control subunit is used for canceling the control on the rotating speed of the wind driven generator when the output power of the wind driven generator is greater than or equal to a preset fifth power reference value and is stable within a third preset time range;

the preset fifth power reference value is greater than the preset first power reference value, and the preset first power reference value is greater than the preset second power reference value.

As a further improvement of the above technical solution, the preset second power reference value is 0.

Further, the reverse crossing resonance band module further comprises a second stabilizing unit, and the second stabilizing unit is used for controlling the rotating speed of the wind driven generator to be stabilized at the rotating speed upper limit value corresponding to the resonance band when the rotating speed of the wind driven generator is reduced to the rotating speed upper limit value corresponding to the resonance band.

Further, the backward crossing resonance band module further comprises a second backward adjusting unit, the second backward adjusting unit performs backward adjustment on the output power of the wind driven generator, and the second backward adjusting unit comprises:

the rotating speed upper limit value limiting stator unit is used for controlling the rotating speed of the wind driven generator to be stabilized at a rotating speed upper limit value corresponding to a resonance band before the output power of the wind driven generator is increased to a preset fourth power reference value within a second preset time range;

the second rotating speed control subunit is used for canceling the control of the rotating speed of the wind driven generator until the output power of the wind driven generator is less than or equal to a preset sixth power reference value and is stable within a fourth preset time range;

the preset fourth power reference value is greater than the preset third power reference value, and the preset third power reference value is greater than the preset sixth power reference value.

Furthermore, the wind driven generator anti-resonance device further comprises a maximum power tracking module, and the maximum power tracking module is used for controlling the output power of the wind driven generator to operate according to a preset maximum power curve when the rotating speed of the wind driven generator reaches the rotating speed upper limit value or the rotating speed lower limit value corresponding to the resonance band.

Compared with the prior art, the invention has the following advantages:

1) according to the anti-resonance control method and device for the wind driven generator, the wind driven generator can be prompted to rapidly pass through the resonance band through controlling the rotating speed and the output power of the wind driven generator, and the resonance phenomenon is avoided, so that the safety of the wind driven generator is improved, and the service life is prolonged;

2) when the rotating speed of the wind driven generator reaches the rotating speed upper limit value or the rotating speed lower limit value corresponding to the resonance band, controlling the rotating speed to be stable at the current rotating speed, and avoiding the wind driven generator from entering the resonance band to run;

3) before controlling the output power to increase or decrease, the output power of the wind driven generator is also reversely adjusted according to the change trend of the output power, and the total change quantity of the output power is increased, namely the change quantity of the torque is increased, so that the angular acceleration of the rotor of the wind driven generator is increased, and the aim of rapidly crossing a resonance band is fulfilled;

4) the anti-resonance control method of the wind driven generator provided by the invention has the advantages of simple program flow, easiness in programming realization and low requirement on controller hardware.

Drawings

FIG. 1 is a graph illustrating a maximum power curve of a wind turbine according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a wind turbine generator passing through a resonance band in a forward direction in an anti-resonance control method for the wind turbine generator according to an embodiment of the present invention;

fig. 3 is a schematic view illustrating that the wind turbine reversely passes through the resonance band in the anti-resonance control method for the wind turbine according to the embodiment of the present invention.

Detailed Description

The following examples are given for the detailed implementation and specific operation of the present invention, but the scope of the present invention is not limited to the following examples.

Referring to fig. 1, a maximum power curve of a certain type of wind turbine provided by an embodiment of the present invention is shown, in which a vertical coordinate P represents an output power of the wind turbine, an abscissa ω represents a rotation speed of the wind turbine, V1-V7 represents a relationship curve between the output power of the wind turbine and the rotation speed ω of the wind turbine at each wind speed, V1 < V2 < V3 < V4 < V5 < V6 < V7, wherein the movement trends of V1-V7 are the same, the magnitude relationship represents a magnitude sequence of values of the vertical coordinate of the highest point of each curve, the maximum output power point of the wind turbine at each wind speed is fitted to form a maximum power curve, and a solid line in fig. 1 is a maximum power curve. In the embodiment of the invention, the wind driven generator operates according to the maximum power curve in a normal operation state.

Referring to fig. 2, fig. 2 is a schematic diagram of the wind turbine generator in the anti-resonance control method for the wind turbine generator according to the embodiment of the present invention, and when the detected rotating speed of the wind turbine generator increases to the lower limit value ω corresponding to the resonance band, the rotating speed of the wind turbine generator increases with the increase of the wind speed_1-And the output power of the wind driven generator is more than or equal to a preset first power reference value P₁When the wind power is in the first preset time range, the current output power of the wind driven generator is controlled to be reduced to a preset second power reference value P₂Promoting the rotating speed of the rotor of the wind driven generator to be rapidly increased so as to rapidly cross the rotating speed value omega corresponding to the resonance frequency point₁And reaches the upper limit value omega of the rotating speed corresponding to the resonance band₁₊When the rotation speed is larger than or equal to omega₁₊And keeping stable within a fifth preset time range, considering that the forward crossing of the resonance band is completed, and then continuously controlling the wind driven generator to operate according to the maximum power curve. Wherein the first preset time is a very small time value, is an instantaneous value, and has a time span of 1-100 milliseconds.

It should be noted that, the detection of the rotational speed of the wind turbine mentioned in the above technical solutions belongs to the prior art, and for example, the method may be implemented by a technical pulse detection method: the generator speed measuring module processes the pulse and converts the pulse into analog quantity of corresponding rotating speed to be transmitted to a fan main control system, and the main control system software calculates the rotating speed of a motor. The method of detection by mechanical sensing can also be used: the rotation number of the same fluted disc arranged on the main shaft of the fan is detected by using two independent proximity switches, then a 24V pulse signal is output to an overspeed detection module, the overspeed detection module outputs voltage analog quantity of two paths of generators corresponding to the current rotation speed, the voltage analog quantity is sent to a main control system, the main control system computer multiplies a coefficient to convert the voltage analog quantity into the rotation speed of the generator, and the rotation speed of the generator is output to a generator speed measurement module.

In the embodiment of the invention, in order to ensure that the jump from the low rotation speed to the high rotation speed is successfully completed, the rotation speed of the wind driven generator is increased to the rotation speed lower limit value omega corresponding to the resonance band_1-When the wind power generator is in the resonance band, the method also comprises the step of controlling the rotating speed of the wind power generator to be stabilized at a rotating speed lower limit value omega corresponding to the resonance band_1-The step (2).

Or before the output power of the wind driven generator is controlled to be reduced to the preset second power reference value within the first preset time range, the method further comprises the step of reversely adjusting the output power of the wind driven generator, and the reversely adjusting step comprises:

controlling the rotating speed of the wind driven generator to be stabilized at a rotating speed lower limit value omega corresponding to a resonance band_1-(ii) a Along with the increase of the wind speed, the output power of the wind driven generator also increases until the output power of the wind driven generator is greater than or equal to a preset fifth power reference value P₅And when the wind power generator is stable within a third preset time range, the control on the rotating speed of the wind power generator is cancelled; wherein the preset fifth power reference value P₅Greater than the preset first power reference value P₁The preset first power reference value P₁Greater than the preset second power reference value P₂。

Due to the fact that the output power of the wind driven generator is carried outBefore the reduction control, the output power of the wind driven generator is reversely (increasingly) regulated, so that the change amount of the output power of the wind driven generator is increased, namely the change amount of the torque is increased, and the change amount of the angular speed of the wind driven generator is further enabled to be changed

Increasing the speed of the wind driven generator from omega when the rotor of the wind driven generator tends to be in an accelerating state_1-Jump rapidly to omega₁₊Across the resonance band.

Specifically, as a preferred technical solution of the embodiment of the present invention, the preset second power reference value P is₂Is 0, i.e. the output current of the wind driven generator is controlled to be 0.

Referring to fig. 3, fig. 3 is a schematic diagram of a wind turbine generator reversely crossing a resonance band in a wind turbine generator anti-resonance control method according to an embodiment of the present invention, and as a wind speed decreases, it is detected that a rotation speed of the wind turbine generator decreases to a rotation speed upper limit value ω corresponding to the resonance band₁₊And the output power of the wind driven generator is more than or equal to a preset third power reference value P₃In time, the output power of the wind driven generator is controlled to be increased to a preset fourth power reference value P within a second preset time range₄The rotating speed of the rotor of the wind driven generator is rapidly reduced, so that the rotating speed value omega corresponding to the resonance frequency point is rapidly crossed₁And reaches the lower limit value omega of the rotating speed corresponding to the resonance band_1-When the rotation speed is less than or equal to omega_1-And if the voltage is kept stable within the sixth preset time, the reverse crossing of the resonance band is considered to be completed, and then the wind driven generator is continuously controlled to operate according to the maximum power curve. The second preset time is a very small time value, is an instantaneous value, and has a time span of millisecond.

Here, the fourth power reference value P₄The optimal set value can be obtained according to a plurality of tests, and of course, the rated output power of the wind driven generator can also be set according to the power grade of the wind driven generator.

In the embodiment of the invention, to ensure the speed of rotationThe method comprises the steps of jumping from a high rotating speed to a low rotating speed, and controlling the rotating speed of the wind driven generator to be stabilized at the rotating speed upper limit value omega corresponding to the resonance band when the rotating speed of the wind driven generator is reduced to the rotating speed upper limit value corresponding to the resonance band₁₊The step (2).

Or, the output power of the wind driven generator is controlled to be increased to a preset fourth power reference value P within a second preset time range₄Before, the method also comprises a step of reversely regulating the output power of the wind driven generator, wherein the step of reversely regulating comprises the following steps: controlling the rotating speed of the wind driven generator to be stabilized at the rotating speed upper limit value omega corresponding to the resonance band₁₊As the wind speed decreases, the output power of the wind turbine decreases, and the output power of the wind turbine decreases to be less than or equal to a preset sixth power reference value P₆And when the wind power generator is stable within a fourth preset time range, the control on the rotating speed of the wind power generator is cancelled; wherein the preset fourth power reference value P₄Is greater than the preset third power reference value P₃The preset third power reference value P₃Is greater than the preset sixth power reference value P₆。

Because the output power of the wind driven generator is adjusted reversely (reduced) before the output power of the wind driven generator is increased and controlled, the change amount of the output power of the wind driven generator is increased, namely the change amount of the torque is increased, and the change amount of the angular speed of the wind driven generator is further caused

Increasing the speed of the wind driven generator from omega when the rotor of the wind driven generator tends to be in a reverse acceleration state₁₊Jump rapidly to omega_1-Across the resonance band.

In the embodiment of the invention, the output power of the wind driven generator is adjusted based on the controller, and the controller of the wind driven generation system also has various methods for adjusting the output power of the wind driven generator. For example, the wind power generation system includes a wind power generator, a rectification module, a dc/dc converter, and a controller, wherein the wind power generator converts wind energy into electric energy and outputs three-phase ac power to the rectification module, the rectification module rectifies the three-phase ac power output by the wind power generator and outputs dc power to the dc/dc converter, the dc/dc converter transforms the dc power, and the controller adjusts a duty ratio of a power switching tube in the dc/dc converter to adjust output power of the wind power generator. The method for adjusting the output power of the wind driven generator by the controller can be as follows: the output power of the wind driven generator is adjusted through a proportional-integral algorithm, wherein the proportional-integral algorithm belongs to a relatively mature algorithm in the prior art and is not described herein any more.

It should be noted that, in the embodiment of the present invention, after the rotation speed of the wind turbine reaches the rotation speed upper limit value or the rotation speed lower limit value corresponding to the resonance band, the output power of the wind turbine is controlled to operate according to a preset maximum power curve, where the maximum power curve is a connection curve of maximum output power points of the wind turbine at each wind speed.

The invention also provides an anti-resonance control device of the wind driven generator, which comprises a forward crossing resonance band module and a reverse crossing resonance band module,

corresponding to the embodiment of the method shown in fig. 2 of the present invention, the forward direction crossing resonance band module includes a first rotation speed detecting unit, a first power detecting unit, a first comparing unit and a first power controlling unit, wherein,

the first rotating speed detection unit is used for detecting the rotating speed of the wind driven generator;

the first power detection unit is used for detecting the output power of the wind driven generator;

the first comparison unit is used for comparing whether the rotating speed of the wind driven generator is increased to a rotating speed lower limit value corresponding to a resonance band or not and comparing whether the output power of the wind driven generator is greater than or equal to a preset first power reference value or not;

and when the first comparison unit compares that the rotating speed of the wind driven generator is increased to the rotating speed lower limit value corresponding to the resonance band and the output power of the wind driven generator is greater than or equal to the preset first power reference value, the first power control unit controls the output power of the wind driven generator to be reduced to the preset second power reference value within a first preset time range so as to enable the rotating speed of the wind driven generator to be equal to or greater than the rotating speed upper limit value corresponding to the resonance band.

Corresponding to the embodiment of the method shown in fig. 3 of the present invention, the backward pass through resonance band module includes a second rotation speed detection unit, a second power detection unit, a second comparison unit and a second power control unit, wherein,

the second rotating speed detection unit is used for detecting the rotating speed of the wind driven generator;

the second power detection unit is used for detecting the output power of the wind driven generator;

the second comparison unit is used for comparing whether the rotating speed of the wind driven generator is reduced to a rotating speed upper limit value corresponding to a resonance band or not and comparing whether the output power of the wind driven generator is larger than or equal to a preset third power reference value or not;

and the second power control unit is used for controlling the output power of the wind driven generator to be increased to a preset fourth power reference value within a second preset time range when the second comparison unit compares that the rotating speed of the wind driven generator is reduced to the rotating speed upper limit value corresponding to the resonance band and the output power of the wind driven generator is greater than or equal to a preset third power reference value, so that the rotating speed of the wind driven generator is smaller than or equal to the rotating speed lower limit value corresponding to the resonance band.

Specifically, the forward crossing resonance band module further comprises a first stabilizing unit, and the first stabilizing unit is further configured to control the rotating speed of the wind turbine generator to be stabilized at the rotating speed lower limit value corresponding to the resonance band when the rotating speed of the wind turbine generator is increased to the rotating speed lower limit value corresponding to the resonance band.

Specifically, the forward direction crossing resonance band module further includes a first reverse direction adjustment unit, the first reverse direction adjustment unit is used for performing reverse direction adjustment on the output power of the wind driven generator, and the first reverse direction adjustment unit includes:

the rotating speed lower limit value limiting stator unit is used for controlling the rotating speed of the wind driven generator to be stabilized at a rotating speed lower limit value corresponding to a resonance band before the output power of the wind driven generator is reduced to a preset second power reference value within a first preset time range;

the first speed control subunit is used for canceling the control on the rotating speed of the wind driven generator until the output power of the wind driven generator is greater than or equal to a preset fifth power reference value and is stable within a third preset time range;

the preset fifth power reference value is greater than the preset first power reference value, and the preset first power reference value is greater than the preset second power reference value.

As a further improvement of the above technical solution, the preset second power reference value is 0.

Specifically, the reverse crossing resonance band module further comprises a second stabilizing unit, and the second stabilizing unit is used for controlling the rotating speed of the wind driven generator to be stabilized at the rotating speed upper limit value corresponding to the resonance band when the rotating speed of the wind driven generator is reduced to the rotating speed upper limit value corresponding to the resonance band.

Specifically, the backward pass-through resonance band module further includes a second backward adjustment unit, the second backward adjustment unit performs backward adjustment on the output power of the wind turbine, and the second backward adjustment unit includes:

the rotating speed upper limit value limiting stator unit is used for controlling the rotating speed of the wind driven generator to be stabilized at a rotating speed upper limit value corresponding to a resonance band before the output power of the wind driven generator is increased to a preset fourth power reference value within a second preset time range;

the second rotating speed control subunit is used for canceling the control of the rotating speed of the wind driven generator until the output power of the wind driven generator is less than or equal to a preset sixth power reference value and is stable within a fourth preset time range;

the preset fourth power reference value is greater than the preset third power reference value, and the preset third power reference value is greater than the preset sixth power reference value.

Specifically, the control of the output power of the wind driven generator is realized by a controller, the wind driven generator converts wind energy into electric energy and outputs three-phase alternating current to a rectification module, the rectification module rectifies the three-phase alternating current output by the wind driven generator and outputs direct current to a direct current/direct current converter, the direct current/direct current converter transforms the direct current, and the controller adjusts the duty ratio of a power switch tube in the direct current/direct current converter so as to adjust the output power of the wind driven generator.

Specifically, the anti-resonance device of the wind driven generator further comprises a maximum power tracking module, and the maximum power tracking module is used for controlling the output power of the wind driven generator to operate according to a preset maximum power curve when the rotating speed of the wind driven generator reaches an upper rotating speed limit value or a lower rotating speed limit value corresponding to a resonance band.

As a further improvement of the above technical solution, the maximum power curve is a connection curve of maximum output power points of the wind turbine at each wind speed.

The working process and the control principle of the anti-resonance device are as follows: when the wind driven generator operates normally and stably, the output power is controlled to follow the maximum power curve, and the mechanical motion equation of the wind driven generator is satisfied:

wherein T is dragging torque (N.m) generated by the impeller of the wind driven generator, and T_ZIs the electromagnetic torque (N.m) of the wind power generator, and J is the moment of inertia (Kg.m)²) Omega is the rotational angular velocity (rad/s) of the wind turbine rotor,

angular acceleration (rad/s) that can be seen as the rotation of the rotor of a wind turbine²)。

When the wind speed is in an increasing trend, the rotating speed of the wind driven generator is increased to a rotating speed lower limit value omega corresponding to a resonance band_1-And the output power reaches a preset first power reference value P₁When the instantaneous output power of the wind driven generator is reduced, namely the instantaneous output current is reduced, the instantaneous rotating speed n of the motor cannot be suddenly changed, so that the electromagnetic torque T of the wind driven generator is reduced due to the reduction of the output current_ZThe instantaneous rotating speed of the wind wheel of the wind driven generator can not be suddenly changed, namely the instantaneous dragging torque T generated by the impeller of the wind driven generator is not changedAlternatively, one can obtain:

namely, the rotor of the wind driven generator tends to be in an accelerating state, so that the rotating speed of the wind driven generator is forced to increase and rapidly pass through a resonance band to reach the rotating speed upper limit value omega corresponding to the resonance band₁₊And the wind power generator is kept stable in a fifth preset time range, and then the wind power generator is controlled to operate according to the maximum power curve.

Similarly, when the wind speed is in a decreasing trend, the rotating speed of the wind driven generator is reduced to the rotating speed upper limit value omega corresponding to the resonance band₁₊And the output power reaches a preset third power reference value P₃At the moment, the instantaneous output power of the wind driven generator is increased, namely the instantaneous output current is increased, the instantaneous rotating speed n of the motor cannot be suddenly changed, and therefore the electromagnetic torque T of the wind driven generator is enabled to be increased by the increase of the output current_ZThe instantaneous rotating speed of the wind wheel of the wind driven generator is increased, namely the instantaneous dragging torque T generated by the impeller of the wind driven generator is not changed, so that the following conditions can be obtained:

namely, the rotor of the wind driven generator tends to be in a reverse acceleration state, so that the rotating speed of the wind driven generator is forced to be rapidly reduced and rapidly pass through a resonance band to reach a rotating speed lower limit value omega corresponding to the resonance band_1-And the wind power generator is stable in the sixth preset time, and then the wind power generator is controlled to operate according to the maximum power curve.

Meanwhile, before the positive direction and the negative direction of the wind driven generator pass through the resonance band, the output power of the wind driven generator is also adjusted in the reverse direction, so that the total change quantity of the output power is increased, namely the change quantity of the torque is increased, and the aim of increasing the angular acceleration of the rotor of the wind driven generator is fulfilled. The specific control method comprises the following steps: before the output power of the wind driven generator is controlled to be instantly reduced, the rotating speed of the wind driven generator is controlled to be stabilized at a rotating speed lower limit value omega corresponding to a resonance band_1-A period of time; the output power of the wind driven generator is increased to a preset fifth power reference value P along with the increase of the wind speed₅When the wind power generator is started, the control on the rotating speed of the wind power generator is cancelled; in controlling wind power generatorBefore the output power is increased instantly, the rotating speed of the wind driven generator is controlled to be stabilized at the rotating speed upper limit value omega corresponding to the resonance band₁₊A period of time; the output power of the wind power generator is reduced to a preset sixth power reference value P along with the reduction of the wind speed₆And when the wind power generator is in the normal state, the control on the rotating speed of the wind power generator is cancelled.

In the invention, when the rotating speed of the wind driven generator reaches the rotating speed upper limit value omega corresponding to the resonance band₁₊Or a lower limit value ω_1-First, the rotational speed limit control is performed (the current rotational speed is stabilized).

It should be noted that the rotational angular velocity ω (rad/s) of the wind turbine rotor and the rotational speed n (r/min) of the wind turbine rotor may be mutually converted, and in a case where the unit is not specifically illustrated, the rotational speed of the wind turbine in the embodiment of the present invention may refer to the rotational angular velocity ω (rad/s) of the wind turbine rotor or the rotational speed n (r/min) of the wind turbine rotor.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.