A dual-mode control method for a main control system of a wind turbine generator set

Abstract

The present invention relates to the field of wind turbine main control system control technology, and in particular to a dual-mode control method for a wind turbine main control system, including dividing the wind turbine dual-mode operation speed interval into a full-power mode power generation operation speed interval, a double-feed mode power generation operation speed interval, and a mode switching transition speed interval; the mode switching transition speed interval includes the wind turbine tower resonance speed interval; the wind turbine main control system dual-mode control is divided into full-power mode power generation control, double-feed mode power generation control, full-power mode switching double-feed mode control, and double-feed mode switching full-power mode control; the full-power mode switching double-feed mode control and the double-feed mode switching full-power mode control both control the wind turbine speed to quickly pass through the mode switching transition speed interval at 0kW power. Through this control method, it is possible to avoid excessive vibration and fatigue damage of the tower caused by long-term operation in the resonance speed interval of the wind turbine tower.

Description

Technical Field

[0001] The invention relates to the technical field of wind turbine generator set main control system control, and in particular to a dual-mode control method for a wind turbine generator set main control system. Background Art

[0002] In order to improve the power generation of doubly-fed wind turbines, the dual-mode transformation technology of doubly-fed wind turbines has been gradually applied in recent years. The converter and main control system of the doubly-fed wind turbines are transformed into dual-modes, so that the doubly-fed wind turbines have two power generation modes: full power mode and doubly-fed mode. For example, in the prior art, there is a Chinese invention patent document with a publication number of CN104269884A and a publication date of January 7, 2015.

[0003] The full-power mode has higher power generation efficiency under low wind conditions and can run at a lower speed, which can increase the operating time of the wind turbine and increase the power generation of the wind turbine. At present, after the dual-mode transformation of the doubly-fed wind turbine, the main control system will lower the lower limit operating speed setting of the wind turbine so that the operating speed range covers or enters the wind turbine tower resonance speed range. If the wind turbine generates electricity and operates in the tower resonance speed range for a long time, it is easy to cause the tower vibration to exceed the limit and cause fatigue damage to the tower. Summary of the invention

[0004] In order to solve the above technical problems, the present invention proposes a dual-mode control method for the main control system of a wind turbine generator set. The method prevents the wind turbine generator set from generating electricity and operating in the tower resonance speed range, and controls the wind turbine generator set to quickly pass through the tower resonance speed range during mode switching control, thereby avoiding excessive vibration and fatigue damage of the wind turbine generator set tower.

[0005] The present invention is achieved by adopting the following technical solutions:

[0006] A dual-mode control method for a main control system of a wind turbine generator set, characterized by comprising:

[0007] Dividing the wind turbine generator set dual-mode operation speed interval: dividing the wind turbine generator set dual-mode operation speed interval into three intervals: a full-power mode power generation operation speed interval, a double-fed mode power generation operation speed interval, and a mode switching transition speed interval; the mode switching transition speed interval includes a wind turbine generator set tower resonance speed interval;

[0008] Divide the dual-mode control functional blocks of the main control system of the wind turbine generator set: divide the dual-mode control of the main control system of the wind turbine generator set into four control functional blocks: full-power mode power generation control, double-fed mode power generation control, full-power mode switching to double-fed mode control and double-fed mode switching to full-power mode control; when the switching conditions between full-power mode power generation control and double-fed mode power generation control are met, the power of the wind turbine generator set is reduced to 0kW by switching the full-power mode to double-fed mode control or the double-fed mode to full-power mode control. Under the 0kW power state, the control target speed value of the wind turbine generator set is increased to the double-fed mode grid-connected speed or reduced to the full-power mode grid-connected speed, and the speed of the wind turbine generator set is controlled to increase or decrease and pass through the mode switching transition speed interval to realize the switching between full-power mode power generation control and double-fed mode power generation control.

[0009] The lower limit value of the full-power mode power generation operation speed range GenSpd_1> the lower limit value of the full-power mode operation speed of the wind turbine converter ConvSpd_1, the upper limit value of the full-power mode power generation operation speed range GenSpd_2< the lower limit value of the tower resonance speed range TowerResonantSpd_Low, and the full-power mode power generation operation speed range and the wind turbine tower resonance speed range have no intersection.

[0010] The lower limit value GenSpd_3 of the doubly fed mode power generation operating speed range> the lower limit value ConvSpd_2 of the doubly fed mode operating speed of the wind turbine generator converter, and the lower limit value GenSpd_3> the upper limit value TowerResonantSpd_High of the tower resonance speed range, the upper limit value GenSpd_4 of the doubly fed mode power generation operating speed range=the rated speed GenSpdRated of the wind turbine generator, and the doubly fed mode power generation operating speed range and the tower resonance speed range of the wind turbine generator have no intersection.

[0011] The mode switching transition speed interval lower limit value GenSpd_5 = ​​the full power mode power generation operation speed interval upper limit value GenSpd_2, and the mode switching transition speed interval upper limit value GenSpd_6 = the double-fed mode power generation operation speed interval lower limit value GenSpd_3.

[0012] The full-power mode power generation control specifically includes: controlling the wind turbine generator set to operate and generate power within the full-power mode power generation operating speed range; the double-fed mode power generation control specifically includes: controlling the wind turbine generator set to operate and generate power within the double-fed mode power generation operating speed range.

[0013] The full power mode switching double-fed mode control specifically includes the following steps:

[0014] a. Rapidly control the wind turbine power to reduce to 0kW in full power mode power generation control state;

[0015] b. After the power of the wind turbine generator set is reduced to 0kW, the control target speed value of the wind turbine generator set is quickly increased to the double-fed mode grid-connected speed GenConnectSpd_1, and the speed of the wind turbine generator set is controlled to quickly increase through the mode switching transition speed interval under the 0kW power state, and enter the double-fed mode power generation operation speed interval;

[0016] c. After the speed of the wind turbine generator set enters the double-fed mode power generation operation speed range, the wind turbine generator set converter is controlled to switch to the double-fed mode;

[0017] d. The main control system switches to double-fed mode power generation control.

[0018] The dual-feed mode switching full power mode control specifically includes the following steps:

[0019] a. Rapidly control the wind turbine power to reduce to 0kW in the double-fed mode power generation control state;

[0020] b. After the power is reduced to 0kW, the control switches the wind turbine converter to full power mode;

[0021] c. Under the 0kW power state, the control target speed value of the wind turbine generator set is quickly reduced to the full-power mode grid-connected speed GenConnectSpd_2, and the speed of the wind turbine generator set is controlled to quickly reduce through the mode switching transition speed interval and enter the full-power mode power generation operation speed interval;

[0022] d. After the wind turbine generator speed enters the full-power mode power generation operation speed range, the main control system switches to full-power mode power generation control.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] 1. In the present invention, since the wind turbine generator set is prone to vibration when generating electricity in the tower resonance speed zone, the full power mode switching double-fed mode control and the double-fed mode switching full power mode control both control the wind turbine generator set speed to quickly pass through the mode switching transition speed interval at 0kW power, which can reduce the exciting force of the excitation source of torque control to a minimum, and avoid the tower vibration exceeding the limit when passing through the mode switching transition speed interval. Since the mode switching transition speed interval includes the wind turbine generator set tower resonance speed interval, quickly passing through the mode switching transition speed interval also quickly passes through the wind turbine generator set tower resonance speed interval, which can avoid the tower vibration exceeding the limit and fatigue damage caused by long-term operation in the wind turbine generator set tower resonance speed interval.

[0025] 2. The present invention divides the dual-mode operation speed interval of the wind turbine generator set into: a full-power mode power generation operation speed interval, a double-fed mode power generation operation speed interval, and a mode switching transition speed interval. When executing full-power mode power generation control and double-fed mode power generation control, the speed of the wind turbine generator set is controlled to operate in the corresponding power generation operation speed interval that has no intersection with the wind turbine generator set tower resonance speed interval. When executing full-power mode switching double-fed mode control and double-fed mode switching full-power mode control, the speed of the wind turbine generator set is controlled to quickly pass through the tower resonance speed interval, which can avoid excessive vibration and fatigue damage of the wind turbine generator set tower. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, wherein:

[0027] Figure 1 It is a schematic diagram of the division of the dual-mode operation speed range of the wind turbine generator set in the present invention;

[0028] Figure 2 This is a flow chart of full power mode power generation control in the present invention;

[0029] Figure 3 This is a control flow chart of double-fed mode power generation in the present invention;

[0030] Figure 4 This is a control flow chart of switching from full power mode to double-fed mode in the present invention;

[0031] Figure 5 This is a control flow chart of switching from the double-fed mode to the full-power mode in the present invention. DETAILED DESCRIPTION

[0032] Example 1

[0033] As a basic implementation mode of the present invention, the present invention includes a dual-mode control method for a main control system of a wind turbine generator set, including dividing the wind turbine generator set dual-mode operation speed interval and dividing the wind turbine generator set main control system dual-mode control function block. Dividing the wind turbine generator set dual-mode operation speed interval specifically refers to: dividing the wind turbine generator set dual-mode operation speed interval into three intervals: a full power mode power generation operation speed interval, a double-fed mode power generation operation speed interval, and a mode switching transition speed interval. The mode switching transition speed interval includes a wind turbine generator set tower resonance speed interval.

[0034] Dividing the dual-mode control functional blocks of the main control system of the wind turbine generator set specifically refers to: dividing the dual-mode control of the main control system of the wind turbine generator set into four control functional blocks: full power mode power generation control, double-fed mode power generation control, full power mode switching double-fed mode control and double-fed mode switching full power mode control.

[0035] When the switching conditions between full-power mode power generation control and double-fed mode power generation control are met, the power of the wind turbine generator set is reduced to 0kW by switching the full-power mode to the double-fed mode control or the double-fed mode to the full-power mode control. Under the 0kW power state, the control target speed value of the wind turbine generator set is increased to the double-fed mode grid-connected speed or reduced to the full-power mode grid-connected speed. The speed of the wind turbine generator set is controlled to increase or decrease and quickly pass through the mode switching transition speed interval, thereby realizing the switching between full-power mode power generation control and double-fed mode power generation control.

[0036] Example 2

[0037] As the best embodiment of the present invention, the present invention includes a dual-mode control method for a main control system of a wind turbine generator set, including dividing the wind turbine generator set into dual-mode operating speed intervals and dividing the wind turbine generator set main control system into dual-mode control function blocks.

[0038] Dividing the wind turbine generator set dual-mode operation speed range specifically refers to: dividing the wind turbine generator set dual-mode operation speed range into three ranges: full power mode power generation operation speed range, double-fed mode power generation operation speed range and mode switching transition speed range. The wind turbine generator set dual-mode operation speed range division diagram is shown in the attached manual. Figure 1 shown.

[0039] Specifically, the lower limit value of the full-power mode power generation operation speed range GenSpd_1> the lower limit value of the full-power mode operation speed of the wind turbine converter ConvSpd_1, the upper limit value of the full-power mode power generation operation speed range GenSpd_2< the lower limit value of the tower resonance speed range TowerResonantSpd_Low, and the full-power mode power generation operation speed range and the wind turbine tower resonance speed range have no intersection.

[0040] The lower limit value GenSpd_3 of the doubly fed mode power generation operating speed range> the lower limit value ConvSpd_2 of the doubly fed mode operating speed of the wind turbine generator converter, and the lower limit value GenSpd_3> the upper limit value TowerResonantSpd_High of the tower resonance speed range, the upper limit value GenSpd_4 of the doubly fed mode power generation operating speed range=the rated speed GenSpdRated of the wind turbine generator, and the doubly fed mode power generation operating speed range and the tower resonance speed range of the wind turbine generator have no intersection.

[0041] The mode switching transition speed interval lower limit value GenSpd_5 = ​​the full power mode power generation operation speed interval upper limit value GenSpd_2, the mode switching transition speed interval upper limit value GenSpd_6 = the double-fed mode power generation operation speed interval lower limit value GenSpd_3, and the mode switching transition speed interval includes the wind turbine tower resonance speed interval.

[0042] Dividing the dual-mode control functional blocks of the main control system of the wind turbine generator set specifically refers to: dividing the dual-mode control of the main control system of the wind turbine generator set into four control functional blocks: full-power mode power generation control, double-fed mode power generation control, full-power mode switching to double-fed mode control, and double-fed mode switching to full-power mode control. When the switching conditions between full-power mode power generation control and double-fed mode power generation control are met, the power of the wind turbine generator set is reduced to 0kW by switching the full-power mode to double-fed mode control or the double-fed mode to full-power mode control. Under the 0kW power state, the control target speed value of the wind turbine generator set is increased to the double-fed mode grid-connected speed or reduced to the full-power mode grid-connected speed, and the speed of the wind turbine generator set is controlled to increase or decrease and pass through the mode switching transition speed interval to realize the switching between full-power mode power generation control and double-fed mode power generation control.

[0043] Furthermore, when performing full-power mode power generation control, the wind turbine generator set is controlled to operate within the full-power mode power generation operating speed range to avoid operating in the wind turbine generator set tower resonance speed range. The full-power mode power generation control switching double-fed mode power generation control control conditions are judged in real time. When the conditions are met, the full-power mode switching double-fed mode control is executed. The full-power mode power generation control flow chart refers to the attached manual Figure 2 shown.

[0044] In the double-fed mode power generation control, the wind turbine generator set is controlled to operate within the double-fed mode power generation operating speed range to avoid operating in the wind turbine generator set tower resonance speed range. The double-fed mode power generation control switching full-power mode power generation control control conditions are judged in real time. When the conditions are met, the double-fed mode switching full-power mode control is executed. The double-fed mode power generation control flow chart refers to the attached manual Figure 3 shown.

[0045] Further, the full power mode switches to the dual-fed mode control, refer to the attached manual Figure 4 , including the following steps:

[0046] a. In the full power mode power generation control state, the wind turbine power is quickly controlled to decrease to 0kW at a rate of change of not less than 5% of the rated power / s.

[0047] b. After the power of the wind turbine generator set is reduced to 0kW, the control target speed value of the wind turbine generator set is rapidly increased to the double-fed mode grid-connected speed GenConnectSpd_1 at a rate of change of not less than 2.5% of the rated speed / s. Under the 0kW power state, the speed of the wind turbine generator set is rapidly increased through the mode switching transition speed interval and enters the double-fed mode power generation operation speed interval;

[0048] c. After the speed of the wind turbine generator set enters the double-fed mode power generation operation speed range, the wind turbine generator set converter is controlled to switch to the double-fed mode;

[0049] d. The main control system switches to double-fed mode power generation control.

[0050] Further, the double-fed mode switches to full power mode control, refer to the attached manual Figure 5 , including the following steps:

[0051] a. In the double-fed mode power generation control state, the wind turbine power is quickly controlled to reduce to 0kW at a rate of change of not less than 5% of the rated power / s;

[0052] b. After the power is reduced to 0kW, the control switches the wind turbine converter to full power mode;

[0053] c. Under the 0kW power state, the control target speed value of the wind turbine generator set is rapidly reduced to the full-power mode grid-connected speed GenConnectSpd_2 at a rate of change of not less than 2.5% of the rated speed / s, and the speed of the wind turbine generator set is controlled to rapidly reduce through the mode switching transition speed interval and enter the full-power mode power generation operation speed interval;

[0054] d. After the wind turbine generator speed enters the full-power mode power generation operation speed range, the main control system switches to full-power mode power generation control.

[0055] Both the full-power mode switching double-fed mode control and the double-fed mode switching full-power mode control control the wind turbine speed to quickly pass through the mode switching transition speed range at 0kW power. Since the mode switching transition speed range includes the wind turbine tower resonance speed range, quickly passing through the mode switching transition speed range also quickly passes through the wind turbine tower resonance speed range, which can avoid long-term operation in the wind turbine tower resonance speed range, resulting in tower vibration exceeding the limit and fatigue damage.

[0056] In summary, after reading the present invention document, ordinary technicians in this field can make various other corresponding transformation schemes based on the technical scheme and technical concept of the present invention without creative mental labor, which all fall within the scope of protection of the present invention.

Claims

1. A dual-mode control method for a main control system of a wind turbine generator set, characterized in that: include: Dividing the wind turbine generator set dual-mode operation speed interval: dividing the wind turbine generator set dual-mode operation speed interval into three intervals: a full-power mode power generation operation speed interval, a double-fed mode power generation operation speed interval, and a mode switching transition speed interval; the mode switching transition speed interval includes a wind turbine generator set tower resonance speed interval; Divide the dual-mode control functional blocks of the main control system of the wind turbine generator set: divide the dual-mode control of the main control system of the wind turbine generator set into four control functional blocks: full-power mode power generation control, double-fed mode power generation control, full-power mode switching to double-fed mode control, and double-fed mode switching to full-power mode control; when the switching conditions between full-power mode power generation control and double-fed mode power generation control are met, the power of the wind turbine generator set is reduced to 0kW by switching the full-power mode to double-fed mode control or the double-fed mode to full-power mode control. Under the 0kW power state, the control target speed value of the wind turbine generator set is increased to the double-fed mode grid-connected speed or reduced to the full-power mode grid-connected speed, and the speed of the wind turbine generator set is controlled to increase or decrease and pass through the mode switching transition speed interval to realize the switching between full-power mode power generation control and double-fed mode power generation control; Lower limit of the speed range for full power mode power generation >Lower speed limit of wind turbine converter in full power mode , upper limit of the speed range of full power mode power generation operation <Lower limit of tower resonance speed range , the full-power mode power generation operation speed range and the wind turbine tower resonance speed range have no intersection; The lower limit of the speed range of the double-fed mode power generation operation >Lower speed limit of wind turbine converter in double-fed mode , and the lower limit >Tower resonance speed range upper limit , upper limit of the speed range of the double-fed mode power generation operation = Rated speed of wind turbine , the speed range of the double-fed mode power generation operation and the wind turbine tower resonance speed range have no intersection; Mode switching transition speed range lower limit = Upper limit of the speed range for full power mode power generation , mode switching transition speed range upper limit =Lower limit of the speed range of the double-fed mode power generation operation .

2. A dual-mode control method for a main control system of a wind turbine generator set according to claim 1, characterized in that: The full-power mode power generation control specifically includes: controlling the wind turbine generator set to operate and generate power within the full-power mode power generation operating speed range; the double-fed mode power generation control specifically includes: controlling the wind turbine generator set to operate and generate power within the double-fed mode power generation operating speed range.

3. A dual-mode control method for a main control system of a wind turbine generator set according to claim 2, characterized in that: The full power mode switching double-fed mode control specifically includes the following steps: a. Rapidly control the wind turbine power to reduce to 0kW in full power mode power generation control state; b. After the wind turbine power is reduced to 0kW, the control target speed value of the wind turbine is quickly increased to the grid-connected speed in the double-fed mode. , under the 0kW power state, the wind turbine generator speed is controlled to quickly increase through the mode switching transition speed range and enter the double-fed mode power generation operation speed range c. After the speed of the wind turbine generator set enters the double-fed mode power generation operation speed range, the wind turbine generator set converter is controlled to switch to the double-fed mode; d. The main control system switches to double-fed mode power generation control.

4. A dual-mode control method for a main control system of a wind turbine generator set according to claim 2, characterized in that: The dual-feed mode switching full power mode control specifically includes the following steps: a. Rapidly control the wind turbine power to reduce to 0kW in the double-fed mode power generation control state; b. After the power is reduced to 0kW, the control switches the wind turbine converter to full power mode; c. Under the 0kW power state, quickly reduce the control target speed value of the wind turbine to the full power mode grid-connected speed , control the speed of the wind turbine generator set to quickly reduce through the mode switching transition speed range and enter the full power mode power generation operation speed range; d. After the wind turbine generator speed enters the full-power mode power generation operation speed range, the main control system switches to full-power mode power generation control.

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