阅读说明：本技术 风力发电机组及其避转速控制方法、装置 (Wind generating set and rotation avoiding speed control method and device thereof ) 是由 张新丽 于 2020-06-28 设计创作，主要内容包括：提供了一种风力发电机组及其避转速控制方法、装置。所述方法包括：当接收到限功率运行的指令时,确定所述指令要求的功率值上限；确定所述要求的功率值上限是否处于与避转速区间对应的避功率区间；当处于所述避功率区间时,将风力发电机组的最大允许功率值设定为所述避功率区间的下边界值,其中,所述避功率区间的上边界值为基于避转速区间的上边界值确定的功率值,所述避功率区间的下边界值为基于避转速区间的下边界值确定的功率值,其中,避转速区间和避功率区间为开区间。能够避免风力发电机组在限功率运行状态下转速的运行范围与避转速区间发生重合而导致机组共振异常、载荷超限等的问题,保证了机组运行的安全性和可靠性。(A wind generating set and a speed avoiding control method and device thereof are provided. The method comprises the following steps: when an instruction of power-limited operation is received, determining an upper limit of a power value required by the instruction; determining whether the required power value upper limit is in a power avoidance interval corresponding to the rotation avoidance interval; and when the wind generating set is in the power avoiding interval, setting the maximum allowable power value of the wind generating set as the lower boundary value of the power avoiding interval, wherein the upper boundary value of the power avoiding interval is the power value determined based on the upper boundary value of the rotation avoiding interval, the lower boundary value of the power avoiding interval is the power value determined based on the lower boundary value of the rotation avoiding interval, and the rotation avoiding interval and the power avoiding interval are open intervals. The problems of unit resonance abnormity, load overrun and the like caused by the coincidence of the operating range of the rotating speed of the wind generating set and the rotating speed avoiding interval in the limited power operating state can be avoided, and the safety and the reliability of the unit operation are ensured.)

1. A rotation avoiding speed control method of a wind generating set is characterized by comprising the following steps:

when an instruction of power-limited operation is received, determining an upper limit of a power value required by the instruction;

determining whether the required power value upper limit is in a power avoidance interval corresponding to the rotation avoidance interval;

when the wind generating set is in the power avoiding interval, setting the maximum allowable power value of the wind generating set as the lower boundary value of the power avoiding interval,

wherein, the upper boundary value of the power avoidance interval is a power value determined based on the upper boundary value of the rotation avoidance interval, the lower boundary value of the power avoidance interval is a power value determined based on the lower boundary value of the rotation avoidance interval,

wherein, the interval of avoiding the rotational speed and the interval of avoiding the power are open intervals.

2. The method of claim 1, further comprising:

and when the maximum allowable power value of the wind generating set is not in the power avoiding interval, setting the maximum allowable power value of the wind generating set as the required upper limit of the power value.

3. The method according to claim 1, characterized in that the upper limit value of the power avoidance interval is the product of the upper limit value of the speed avoidance interval and the first predetermined electromagnetic torque,

the lower boundary value of the power avoiding interval is the product of the lower boundary value of the speed avoiding interval and the second preset electromagnetic torque,

wherein the first preset electromagnetic torque is an electromagnetic torque value which needs to stay before passing through the rotation avoiding speed interval from the low rotation speed to the high rotation speed,

and the second preset electromagnetic torque is an electromagnetic torque value when the wind generating set reaches a lower boundary value of the rotation avoiding speed interval.

4. The method of claim 1, further comprising:

identifying whether the wind generating set has the abnormality of repeatedly passing through the rotation avoiding speed interval according to the statistical information that the rotation speed of the generator is in the rotation avoiding speed interval,

wherein, when there is an abnormality, the step of determining whether the requested power value upper limit is in a power avoidance interval corresponding to a rotation avoidance interval is performed.

5. The method of claim 4, wherein the statistical information that the rotation speed of the generator is in the idle speed interval comprises: and the counting time length of the rotating speed of the generator in the rotating speed avoiding interval and/or the counting times of entering the rotating speed avoiding interval.

6. The method of claim 5, wherein the step of identifying whether the wind turbine generator set has an abnormality of repeatedly passing through the stall interval according to the statistical duration of the generator speed in the stall interval comprises:

according to the operation data of the historical operation time period of the wind generating set, determining the speed avoiding duration ratio corresponding to each time interval in the historical operation time period, wherein the speed avoiding duration ratio corresponding to each time interval is as follows: the total duration of a first preset interval with the rotating speed in the rotating speed avoiding interval in the time interval accounts for the proportion of the preset duration;

when the total number of the corresponding time intervals with the rotation avoiding time length in the historical operation period exceeding the preset standard proportion exceeds a first preset number, determining that the wind generating set has the abnormity of repeatedly passing through the rotation avoiding interval,

and the length of each time interval is the preset duration.

7. The method of claim 6, wherein the step of determining that the wind turbine has an anomaly that repeatedly passes through the stall interval comprises:

when the corresponding speed avoiding duration proportion in the historical operation period exceeds a preset standard proportion and the total number of time intervals corresponding to the limited power operation state exceeds a second preset number, determining that the wind generating set has an abnormality of repeatedly passing through a speed avoiding interval;

or when the corresponding speed avoiding duration ratio in the historical operation period exceeds a preset standard ratio and the total number of time intervals corresponding to the preset wind speed period exceeds a third preset number, determining that the wind generating set has the abnormity of repeatedly passing through the speed avoiding interval,

and the preset wind speed section is a wind speed section near the wind speed section corresponding to the rotation avoiding speed interval.

8. The method of claim 6, wherein the step of determining a stall avoidance time period ratio corresponding to each time interval in a historical operating period of a wind turbine generator system based on operating data of the historical operating period comprises:

dividing the operation data of the historical operation time period into M groups of operation data by taking the preset time period as an interval, wherein each group of operation data comprises: n rotating speed values of the generator are collected at N continuous sampling time points;

taking the ratio of the number of the rotating speed values in the first preset interval in the N rotating speed values of each group to N as the corresponding speed avoiding duration ratio of each time interval,

wherein M is an integer greater than 1, and N is an integer greater than 1.

9. The method of claim 6, wherein the preset standard proportion is determined based on at least one of: the method comprises the steps of setting the jump-up duration required by the wind generating set to pass through a rotation avoiding interval from a low rotating speed to a high rotating speed, setting the jump-down duration required by the wind generating set to pass through the rotation avoiding interval from the high rotating speed to the low rotating speed, setting the number of times that the wind generating set can normally pass through the rotation avoiding interval within the preset duration, and setting the length of the preset duration.

10. The method according to claim 9, wherein the predetermined standard ratio is: t is_max*I*J/L，

Wherein, T_maxIndicating the maximum value of the jump-up time length and the jump-down time length, indicating a margin coefficient by I, indicating the preset times of normally passing through a rotation avoiding speed interval in the preset time length by J, and indicating the length of the preset time length by L.

11. A wind generating set avoid rotational speed controlling means, its characterized in that, the device includes:

the device comprises a determining unit, a judging unit and a judging unit, wherein the determining unit determines an upper limit of a power value required by an instruction when the instruction of power-limited operation is received;

the judging unit is used for determining whether the required power value upper limit is in a power avoiding interval corresponding to the rotating speed avoiding interval or not;

a setting unit, setting the maximum allowable power value of the wind generating set as the lower boundary value of the power avoiding interval when the wind generating set is in the power avoiding interval,

wherein, the upper boundary value of the power avoidance interval is a power value determined based on the upper boundary value of the rotation avoidance interval, the lower boundary value of the power avoidance interval is a power value determined based on the lower boundary value of the rotation avoidance interval,

wherein, the interval of avoiding the rotational speed and the interval of avoiding the power are open intervals.

12. A wind turbine generator set, comprising:

a generator comprising a stator and a rotor mechanically coupled to the impeller;

the current transformer is electrically coupled with the stator winding;

a data acquisition module configured to acquire a rotational speed of the generator;

a controller configured to set an electromagnetic torque parameter of the converter to control a rotational speed of the generator, the controller performing the rotational speed avoidance control method of any one of claims 1 to 10.

13. The wind generating set of claim 12, wherein the generator is a permanent magnet generator and the wind generating set is a direct drive type.

14. A computer-readable storage medium, in which a computer program is stored, which, when being executed by a processor, carries out a method for rotational speed avoidance control of a wind park according to any one of claims 1 to 10.

Technical Field

The invention relates to the technical field of wind power generation in general, and in particular relates to a wind generating set and a speed avoiding control method and device thereof.

Background

With the increase of the capacity of the wind generating set, the wind generating set equipped with the high flexible tower gradually becomes a trend due to the characteristics of high power generation performance, low cost and the like. However, due to the low natural frequency of the high-flexibility tower, the frequency doubling component in the operation rotating speed of the unit is overlapped with the natural frequency of the high-flexibility tower. In the conventional design, in order to avoid resonance between the unit and the first-order frequency of the tower at the minimum rotating speed, the value of the minimum rotating speed is limited. However, because the rated rotation speed of some large impeller units is very low at present, if the limit on the minimum rotation speed is met, the range between the minimum rotation speed and the rated rotation speed is too narrow, and the problem of poor power generation performance of the units is caused. In order to solve the problem, the tower resonance can be avoided by increasing the rotation avoiding speed interval while selecting a smaller minimum rotation speed value. However, the rotational speed of the wind turbine is often in or frequently enters a stall avoidance interval, which may cause unit resonance, increased loads, or other safety issues.

Disclosure of Invention

An exemplary embodiment of the present invention is to provide a wind turbine generator system, and a method and an apparatus for controlling a rotational speed of the wind turbine generator system, which can prevent an operating range of a rotational speed of the wind turbine generator system in a power-limited operating state from coinciding with a rotational speed avoiding interval.

According to an exemplary embodiment of the present invention, there is provided a stall control method of a wind turbine generator system, the method including: when an instruction of power-limited operation is received, determining an upper limit of a power value required by the instruction; determining whether the required power value upper limit is in a power avoidance interval corresponding to the rotation avoidance interval; and when the wind generating set is in the power avoiding interval, setting the maximum allowable power value of the wind generating set as the lower boundary value of the power avoiding interval, wherein the upper boundary value of the power avoiding interval is the power value determined based on the upper boundary value of the rotation avoiding interval, the lower boundary value of the power avoiding interval is the power value determined based on the lower boundary value of the rotation avoiding interval, and the rotation avoiding interval and the power avoiding interval are open intervals.

Optionally, the method further comprises: and when the maximum allowable power value of the wind generating set is not in the power avoiding interval, setting the maximum allowable power value of the wind generating set as the required upper limit of the power value.

Optionally, an upper boundary value of the power avoidance interval is a product of an upper boundary value of the rotation avoidance interval and a first preset electromagnetic torque, a lower boundary value of the power avoidance interval is a product of a lower boundary value of the rotation avoidance interval and a second preset electromagnetic torque, the first preset electromagnetic torque is an electromagnetic torque value which needs to stay before the wind turbine generator system passes through the rotation avoidance interval from a low rotation speed to a high rotation speed, and the second preset electromagnetic torque is an electromagnetic torque value when the wind turbine generator system reaches the lower boundary value of the rotation avoidance interval.

Optionally, the method further comprises: and identifying whether the wind generating set has an abnormality of repeatedly passing through the rotation avoiding speed interval according to the statistical information that the rotation speed of the generator is in the rotation avoiding speed interval, wherein when the abnormality exists, the step of determining whether the required power value upper limit is in the power avoiding power interval corresponding to the rotation avoiding speed interval is executed.

Optionally, the statistical information that the rotation speed of the generator is in the rotation avoiding speed interval includes: and the counting time length of the rotating speed of the generator in the rotating speed avoiding interval and/or the counting times of entering the rotating speed avoiding interval.

Optionally, the step of identifying whether the wind generating set has an abnormality of repeatedly passing through the rotation avoiding speed interval according to the statistical duration of the rotation speed of the generator in the rotation avoiding speed interval includes: according to the operation data of the historical operation time period of the wind generating set, determining the speed avoiding duration ratio corresponding to each time interval in the historical operation time period, wherein the speed avoiding duration ratio corresponding to each time interval is as follows: the total duration of a first preset interval with the rotating speed in the rotating speed avoiding interval in the time interval accounts for the proportion of the preset duration; and when the total number of the corresponding time intervals with the speed avoiding duration ratio exceeding the preset standard proportion in the historical operation period exceeds a first preset number, determining that the wind generating set has an abnormality of repeatedly passing through the speed avoiding interval, wherein the length of each time interval is the preset duration.

Optionally, the step of determining that the wind generating set has an abnormality of repeatedly passing through the stall speed interval includes: when the corresponding speed avoiding duration proportion in the historical operation period exceeds a preset standard proportion and the total number of time intervals corresponding to the limited power operation state exceeds a second preset number, determining that the wind generating set has an abnormality of repeatedly passing through a speed avoiding interval; or when the corresponding speed avoidance duration proportion in the historical operation period exceeds a preset standard proportion and the total number of time intervals corresponding to the preset wind speed section exceeds a third preset number, determining that the wind generating set has an abnormality of repeatedly passing through the speed avoidance interval, wherein the preset wind speed section is a wind speed section near the wind speed section corresponding to the speed avoidance interval.

Optionally, the step of determining, according to the operation data of the historical operation period of the wind turbine generator system, a rotation avoiding speed duration ratio corresponding to each time interval in the historical operation period includes: dividing the operation data of the historical operation time period into M groups of operation data by taking the preset time period as an interval, wherein each group of operation data comprises: n rotating speed values of the generator are collected at N continuous sampling time points; and taking the ratio of the number of the rotating speed values in the first preset interval in the N rotating speed values of each group to N as the corresponding speed avoiding duration ratio corresponding to each time interval, wherein M is an integer larger than 1, and N is an integer larger than 1.

Optionally, the preset standard proportion is determined based on at least one of: the method comprises the steps of setting the jump-up duration required by the wind generating set to pass through a rotation avoiding interval from a low rotating speed to a high rotating speed, setting the jump-down duration required by the wind generating set to pass through the rotation avoiding interval from the high rotating speed to the low rotating speed, setting the number of times that the wind generating set can normally pass through the rotation avoiding interval within the preset duration, and setting the length of the preset duration.

Optionally, the preset standard ratio is: t is_maxI J/L, wherein T_maxIndicating the maximum value of the jump-up time length and the jump-down time length, indicating a margin coefficient by I, indicating the preset times of normally passing through a rotation avoiding speed interval in the preset time length by J, and indicating the length of the preset time length by L.

According to another exemplary embodiment of the present invention, there is provided a stall avoidance control apparatus of a wind turbine generator system, the apparatus including: the device comprises a determining unit, a judging unit and a judging unit, wherein the determining unit determines an upper limit of a power value required by an instruction when the instruction of power-limited operation is received; the judging unit is used for determining whether the required power value upper limit is in a power avoiding interval corresponding to the rotating speed avoiding interval or not; and the setting unit is used for setting the maximum allowable power value of the wind generating set as the lower boundary value of the power avoidance interval when the wind generating set is in the power avoidance interval, wherein the upper boundary value of the power avoidance interval is a power value determined based on the upper boundary value of the rotation avoidance interval, the lower boundary value of the power avoidance interval is a power value determined based on the lower boundary value of the rotation avoidance interval, and the rotation avoidance interval and the power avoidance interval are open intervals.

According to another exemplary embodiment of the present invention, there is provided a wind turbine generator system including: a generator comprising a stator and a rotor mechanically coupled to the impeller; the current transformer is electrically coupled with the stator winding; a data acquisition module configured to acquire a rotational speed of the generator; a controller configured to set an electromagnetic torque parameter of the converter to control a rotational speed of the generator, the controller performing the rotational speed avoidance control method as described above.

Optionally, the generator is a permanent magnet generator, and the wind generating set is a direct-drive type.

According to another exemplary embodiment of the invention, a computer-readable storage medium is provided, in which a computer program is stored which, when being executed by a processor, carries out the method for rotational speed avoidance control of a wind park as described above.

According to the wind generating set and the rotation avoiding speed control method and device thereof in the exemplary embodiment of the invention, the problems of set resonance abnormity, load overrun and the like caused by the coincidence of the operation range of the rotation speed and the rotation avoiding speed interval of the wind generating set in the limited power operation state can be avoided, and the safety and the reliability of the set operation are ensured.

Additional aspects and/or advantages of the present general inventive concept will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the general inventive concept.

Drawings

The above and other objects and features of exemplary embodiments of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings which illustrate exemplary embodiments, wherein:

fig. 1 shows a flow chart of a method for rotational speed avoidance control of a wind park according to an exemplary embodiment of the present invention;

FIG. 2 shows a schematic structural view of a wind park according to an exemplary embodiment of the present invention;

FIG. 3 illustrates a schematic diagram of stall avoidance control according to an exemplary embodiment of the present invention;

FIG. 4 illustrates a flow chart of a method of determining a duty cycle duration ratio for each time interval in a historical operating period in accordance with an exemplary embodiment of the present invention;

FIG. 5 illustrates an example of a crew rotation speed frequently in a stall avoidance interval according to an exemplary embodiment of the present invention;

FIG. 6 is a graph illustrating a profile of the idle speed duration ratio according to an exemplary embodiment of the present invention;

fig. 7 shows a block diagram of a stall control device of a wind park according to an exemplary embodiment of the invention.

Detailed Description

Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.

Fig. 1 shows a flow chart of a method for rotational speed avoidance control of a wind park according to an exemplary embodiment of the invention.

In step S10, when an instruction for power-limited operation is received, an upper limit of the power value required by the instruction is determined.

As an example, the instruction for limited power operation may be received from a wind farm central control or a wind farm cluster controller, for example, the wind farm may issue an instruction for limited power operation to the unit for the reason of power limitation, etc.

In step S20, it is determined whether the requested upper limit of the power value is in a bypass interval corresponding to the bypass interval.

As an example, an upper boundary value of the power avoidance interval is a power value determined based on an upper boundary value of the power avoidance interval, and a lower boundary value of the power avoidance interval is a power value determined based on a lower boundary value of the power avoidance interval, where the power avoidance interval and the power avoidance interval are open intervals.

The passing-through control of the rotation avoiding speed/the rotation speed is a rotation speed control function/strategy of the generator, and particularly, the electromagnetic torque of a converter of the wind generating set and the rotation speed of the generator are controlled, so that the wind generating set quickly passes through a certain rotation speed range (namely, a rotation avoiding speed interval) in the power generation process, and the problems of unit resonance, load increase or other problems caused by the fact that the wind generating set stays in the rotation speed range for a long time are prevented. That is, the anti-rotation speed interval mentioned in the present invention may be set in consideration of resonance, load reduction, or other situations, and the present invention is not limited thereto.

Referring to fig. 2, the wind generating set captures wind energy by an impeller, and a generator and a converter form an energy conversion unit to convert the wind energy into electric energy and transmit the electric energy to a power grid. In the example of fig. 2, the generator includes a stator and a rotor mechanically coupled to an impeller. The converter is electrically coupled with the stator winding. The generator is a permanent magnet generator, and magnetic steel is arranged in the rotor. The wind generating set is of a direct-drive type, the converter is a full-power converter, and electric energy converted from wind energy is completely fed into a power grid. A controller of the wind generating set collects wind speed and the current rotating speed of the generator to send an electromagnetic torque control signal to the converter, and current in a stator winding of the generator is controlled to control the rotating speed of the generator. From the pneumatic torque equation T_a＝0.5ρC_qπR³V²It can be seen that the pneumatic torque T_aProportional to the square of the wind speed V, where ρ represents the air density of the environment in which the unit is located, C_qThe torque coefficient of the unit is shown, and R represents the radius of the impeller. The machine set can control the pitch angle of each blade through a pitch control system, so that the energy of the impeller absorbing wind flow is limited, and further the pneumatic torque is adjusted. The generator can control the electromagnetic torque T of the generator while finishing the electric energy conversion_e. From Δ T to T_a-T_eThe dw ═ Δ T/J1 shows the generator speed differential and the aerodynamic torque T_aAnd electromagnetic torque T_eWhere J1 is the moment of inertia and w is the angular velocity. In summary, the whole unit can adjust the pneumatic torque T through a variable pitch mechanism_aAnd electromagnetic torque T_eThe rotating speed control of the unit is realized.

Fig. 3 shows a rotational speed-electromagnetic torque operating curve of the generator, wherein the ordinate indicates the electromagnetic torque and the abscissa indicates the rotational speed. The rotating speed of the unit is between Wsync and Wrated during normal operation, and (Wlow, Whigh) is a rotating speed avoiding interval, Wlow is the lower boundary value of the rotating speed avoiding interval, and Whigh is the upper boundary value of the rotating speed avoiding interval, namely the unit can not stay in the rotating speed interval for a long time. Tlow-max and Thigh-min correspond to the electromagnetic torque control requirements at two rotating speeds of Wlow and Whigh, specifically, when the rotating speed reaches the point A along with the wind speed, the rotating speed can not be continuously increased according to the rotating speed control requirement, the rotating speed is controlled at Wlow, if the wind speed is increased, in order to maintain the rotating speed at Wlow, the electromagnetic torque is continuously increased from TA until the rotating speed reaches Tlow-max (namely, the point B is reached), after the point B is continuously stayed for T1 seconds, the rotating speed is increased at the speed of V1 rad/s until the rotating speed reaches Whigh, namely, the running state reaches the point E, and if the wind speed is further increased, the rotating speed is continuously increased upwards; when the wind speed is reduced at the point E, the rotating speed can not be further reduced according to the requirement of rotating speed control, the rotating speed is controlled at Whigh, if the wind speed is reduced, the electromagnetic torque is continuously reduced from TE until reaching Thigh-min (namely reaching the point D) in order to maintain the rotating speed at Whigh, and after the wind speed is continuously stopped at the point D for T2 seconds, the rotating speed is reduced at the speed of V2 rad/s so as to jump to the point A. Among other things, Wlow and Whigh can be determined based on the design frequency of the unit (e.g., the natural frequency of the structural components including the tower).

As an example, the upper boundary value of the idle interval may be the product of the upper boundary value of the idle interval (i.e., Whigh) and a first preset electromagnetic torque (i.e., Tlow-max), wherein the first preset electromagnetic torque is an electromagnetic torque value to be stopped before traversing the idle interval from a low rotation speed to a high rotation speed.

As an example, the lower boundary value of the power avoidance interval may be a product of the lower boundary value of the speed avoidance interval (i.e., Wlow) and a second preset electromagnetic torque (i.e., TA), where the second preset electromagnetic torque is an electromagnetic torque value of the wind turbine generator system just reaching the lower boundary value of the speed avoidance interval.

Returning to fig. 1, when it is determined in step S20 that the maximum allowable power value of the wind turbine generator system is within the power avoidance interval, step S30 is performed to set the maximum allowable power value of the wind turbine generator system to the lower boundary value of the power avoidance interval. In other words, the power value of the wind turbine generator system is not allowed to exceed the lower boundary value of the power avoidance interval. In addition, feedback may be given to the target of the instruction for transmitting the limited power operation, for example, information that the maximum allowable power value of the wind turbine generator system is set as the lower boundary value of the power avoidance interval is fed back.

When it is determined in step S20 that the maximum allowable power value of the wind turbine generator system is not within the power avoidance interval, step S40 is executed to set the maximum allowable power value of the wind turbine generator system to the required upper limit power value. In other words, the power value of the wind park is not allowed to exceed the required upper power value limit.

As an example, the method for controlling a rotational speed of a wind turbine generator system according to an exemplary embodiment of the present invention may further include: and identifying whether the wind generating set has an abnormality of repeatedly passing through the rotation avoiding speed interval or not according to the statistical information that the rotation speed of the generator is in the rotation avoiding speed interval, wherein when the abnormality is determined, the step S20 is executed.

As an example, the statistical information that the rotation speed of the generator is in the stall avoidance interval may be statistical information that can be used to determine whether the rotation speed of the generator is frequently in or frequently enters the stall avoidance interval. As an example, the statistical information that the rotation speed of the generator is in the idle rotation speed interval may include: and the counting time length of the rotating speed of the generator in the rotating speed avoiding interval and/or the counting times of entering the rotating speed avoiding interval.

As an example, the stall condition of the wind turbine generator system may refer to a condition that the rotation speed of the generator enters or is in a stall interval. As an example, it may be determined that the wind turbine generator set has an abnormality of repeatedly passing through the rotation avoidance interval when the statistical information that the rotation speed of the generator is in the rotation avoidance interval indicates that the rotation speed is often in or frequently enters the rotation avoidance interval beyond a certain degree.

Considering the accuracy of control, a part of intervals can be reserved at two ends in the rotation avoiding interval, and the rotation speed is considered to belong to the normal operation condition in the reserved interval, for example, the statistical information that the rotation speed of the generator is in the rotation avoiding interval may include: the counting time of the first preset interval when the rotating speed of the generator is in the rotating speed avoiding interval and/or the counting times of entering the first preset interval. Here, the first predetermined interval may be: (Wlow + We1, Whigh-We 2).

As an example, the rotational speed of the generator may or may not be equal to the rotational speed of the impeller.

As an example, the step of identifying whether the wind turbine generator set has an abnormality of repeatedly passing through the rotation avoiding speed interval according to the statistical duration of the rotation speed of the generator in the rotation avoiding speed interval may include: according to the operation data of the historical operation time period of the wind generating set, determining the speed avoiding duration ratio corresponding to each time interval in the historical operation time period, wherein the speed avoiding duration ratio corresponding to each time interval is as follows: the total duration of a first preset interval with the rotating speed in the rotating speed avoiding interval in the time interval accounts for the proportion of the preset duration; and when the total number of the corresponding time intervals with the speed avoiding duration ratio exceeding the preset standard proportion in the historical operation period exceeds a first preset number, determining that the wind generating set has an abnormality of repeatedly passing through the speed avoiding interval, wherein the length of each time interval is the preset duration.

As an example, the preset duration may be an interval, and the operation data in the historical operation period is divided into M groups of operation data, where each group of operation data includes: acquiring N rotating speed values of the generator at N continuous sampling time points (namely acquiring the rotating speed value once at each sampling time point to acquire N rotating speed values); and taking the ratio of the number of the rotating speed values in the first preset interval in the N rotating speed values of each group to N as the corresponding speed avoiding duration ratio corresponding to each time interval, wherein M is an integer larger than 1, and N is an integer larger than 1. It will be appreciated that each group corresponds to a time interval, the time intervals corresponding to different groups being different.

For example, the preset standard proportion may indicate the proportion of the total duration of the revolution-avoiding interval in the preset duration in the case of normal revolution-avoiding skip, so that when the proportion of the revolution-avoiding duration corresponding to any time interval exceeds the normal proportion, it may be indicated that the revolution-avoiding condition in the time interval is abnormal.

As an example, the preset standard proportion may be determined based on at least one of: the method comprises the steps of enabling the wind generating set to pass through a rotation avoiding speed interval from a low rotation speed to a high rotation speed for a jump-up time length (namely, (Whigh-Wlow)/V1), enabling the wind generating set to pass through the rotation avoiding speed interval from the high rotation speed to the low rotation speed for a jump-down time length (namely, (Whigh-Wlow)/V2), presetting the number of times of normally passing through the rotation avoiding speed interval in the preset time length, and the length of the preset time length.

As an example, the preset standard ratio may be Ks: t is_maxI J/L, wherein T_maxIndicating the maximum value of the jump-up time length and the jump-down time length, indicating a margin coefficient by I, indicating the preset times of normally passing through a rotation avoiding speed interval in the preset time length by J, and indicating the length of the preset time length by L.

Here, the number of times that the rotation avoiding interval can be normally traversed within the preset time period may be determined according to at least one of an actual operation condition, a simulation, and a human experience. For example, when the length of the preset time period is 20min, the number of times that the rotation avoiding speed interval can be normally traversed within the preset time period may be 10. In order to allow a certain margin for the judgment using the predetermined standard ratio, a certain degree of deviation can be accepted, and a margin coefficient I is added, for example, I can take a value between 1.1 and 1.5. As an example, T_maxThe number may be 10-30s, for example, Wlow is 7rpm, Whigh is 11rpm, V1 is 0.2rpm/s (i.e., the requirement for the avoidance speed control is to pass the avoidance speed interval quickly at 0.2rpm per second), the time for the normal crossing/jumping one-time avoidance speed interval is T1 is T2 (Whigh-Wlow)/V1 is 20s, and the jump-up time (Whigh-Wlow)/V1 and the jump-down time (Whigh-Wlow)/V2 are equal, provided that the jump-up speed V1 and the jump-down speed V2 are equal to each other, the jump-up time (Whigh-Wlow)/V1 and the jump-down time (Whigh-Wlow)/V are equal to each other2) Same, then T_max20 s. For example, when L is 20min, J is 10, I is 1.2, T_maxWhen 20s, the preset standard ratio is 0.2.

Fig. 4 shows a flowchart of a method of determining a duty cycle duration ratio for each time interval in a historical operating period according to an exemplary embodiment of the present invention.

As shown in fig. 4, in step S101, operation data of a historical operation period of the wind turbine generator system is obtained, wherein the operation data includes a rotation speed value.

In step S102, with the preset duration as an interval, the operation data of the historical operation time period is divided into M groups of operation data, specifically, the historical operation time period is divided every other preset duration, and the operation data of each time interval obtained by the division forms a group of operation data. Each set of operating data includes: the method comprises the steps that N rotating speed values of the generator are collected at N continuous sampling time points (namely N operating points), and the N rotating speed values are arranged according to the sequence of the corresponding sampling time points. It will be appreciated that N depends on the length of the preset duration and the running data sampling period.

As an example, the historical operating period may be the last month, and the preset time period may be a value between 10min and 30 min.

In step S103, it is determined whether i is less than or equal to M, where i has an initial value of 1.

When it is determined in step S103 that i is less than or equal to M, step S104 is performed to determine whether j, the initial value of which is 1, is less than or equal to N.

When j is determined to be less than or equal to N in step S104, step S105 is performed to extract the jth rotation speed value w in the ith set of operation data_ijAnd let j equal j + 1.

After step S105, step S106 is executed to determine the jth rotating speed value w in the extracted ith group of operation data_ijWhether greater than (Wlow + We1) and less than (Whigh-We 2).

When determining w in step S106_ijGreater than (Wlow + We1) and less than (Whigh-We2), go to step S107, make Ni equal to Ni +1, and return to executionStep S104 is performed, wherein the initial value of Ni is 0.

When determining w in step S106_ijNot more than (Wlow + We1), or w_ijWhen the value is not less than (Whigh-We2), the step S104 is executed again.

When it is determined in step S104 that j is greater than N, step S108 is executed to make Ki equal to Ni/N so that i is equal to i +1, and execution returns to step S103.

When it is determined in step S103 that i is greater than M, step S109 is performed to record all Ki, i.e., record K1, K2, K3, … …, KM. Here, all Ki are the rotation avoiding time length ratios corresponding to each time interval in the historical operating period.

In the invention, the problem that the unit passes repeatedly in the rotation avoiding interval is considered, as shown in fig. 5, the rotation avoiding interval is (9, 11.5), and fig. 5 shows the condition that the rotation speed of the unit is frequently in the rotation avoiding interval, which can cause the problems of abnormal resonance of the unit, overload and the like. After the analysis of the invention, the reason that the situation is generally that if the external limited power instruction is given, the unit controls the current rotating speed of the generator according to the limited power, and if the rotating speed corresponding to the power limit value is in the rotating speed avoiding interval, as shown in fig. 5, the power limit value is 1MW, and the corresponding rotating speed is 10.5rpm, the rotating speed avoiding function is failed, so that the unit runs in the rotating speed avoiding interval for a long time, and the rotating speed avoiding condition is abnormal.

In the prior art, the abnormal evaluation of the wind generating set repeatedly passing through the rotation avoiding speed interval still falls into the blank, and the main reasons are that: the uncertainty of the reasons is difficult to find in the prototype test, and particularly, the wind field limit electricity has great uncertainty. The following two problems are often caused by the repeated passing of the abnormal rotation avoiding speed interval: firstly, the motor runs in a rotation speed avoiding interval for a long time, and when vibration is increased to a corresponding protection threshold value, shutdown faults are caused; and secondly, the motor runs in the anti-rotation speed interval for a long time or a short time, but the vibration does not reach the corresponding protection threshold value, so that the influence (such as shutdown fault) cannot be seen in a short time, but the loss of the power generation and the fatigue life of the component are brought by long-term accumulation, so that the cost of the loss of the power generation and the damage of the component is caused, but even if the abnormal anti-rotation speed condition is hardly found out as the cause of the problem.

Thus, as an example, it may be determined that there is an abnormality in the wind turbine generator set that repeatedly passes through the stall interval when the rotation speed of the generator is frequently in the stall interval in the limited power operation state.

As an example, when the corresponding speed avoidance duration ratio in the historical operating period exceeds a preset standard ratio and the total number of time intervals corresponding to the limited power operating state exceeds a second preset number, it may be determined that the wind turbine generator set has an abnormality of repeatedly passing through the speed avoidance interval, in other words, it is determined that the abnormal speed avoidance situation and the cause of the abnormal speed avoidance situation is: the maximum rotating speed operating range determined by the unit according to the power limiting instruction is overlapped with the rotating speed avoiding interval, so that the steps S20-S30 are executed to avoid the abnormal rotating speed avoiding condition of the wind generating set as much as possible. Here, the time interval corresponding to the power-limited operation state refers to: the wind generating set is in a power-limited operating state at the time interval.

As another example, it may be determined that the wind turbine generator system has an abnormality of repeatedly passing through a stall avoidance interval when the corresponding stall avoidance duration proportion in the historical operation period exceeds a preset standard proportion and the total number of time intervals corresponding to a preset wind speed segment exceeds a third preset number, where the preset wind speed segment is a wind speed segment near the wind speed segment corresponding to the stall avoidance interval. For example, the wind speed section corresponding to the rotation avoiding rate section is the wind speed section in which the rotation speed enters the rotation avoiding rate section. As an example, the wind speed segment near the wind speed segment corresponding to the stall avoidance interval may be: the wind speed section comprises a wind speed section corresponding to the speed avoidance interval, the lower boundary value of the wind speed section is smaller than the lower boundary value of the wind speed section corresponding to the speed avoidance interval by a first preset value, and the upper boundary value of the wind speed section is larger than the upper boundary value of the wind speed section corresponding to the speed avoidance interval by a second preset value. The time interval corresponding to the preset wind speed section means: and the ambient wind speed value of the wind generating set is in the preset wind speed section at the time interval.

Fig. 6 shows the distribution of the speed avoidance duration ratio Ki corresponding to different time intervals of the wind turbine generator system, the abscissa in the graph indicates the wind speed, the ordinate indicates the value of Ki, the preset standard ratio Ks is 0.2, each point indicates the speed avoidance duration ratio corresponding to the wind turbine generator system at a time interval, therefore, the point where the speed avoidance duration ratio exceeds 0.2 is an abnormal point, otherwise, the point is a normal point. It can be seen that the point set in fig. 6 is an obvious columnar structure, and the wind speed is near 6m/s as the highest point, and at this time, the corresponding wind speed point is exactly the wind speed point corresponding to the anti-rotation speed interval, and the energy provided by the wind makes the rotation speed between the upper boundary value and the lower boundary value of the anti-rotation speed interval, that is, if the wind speed is smaller, the rotation speed stays at the lower boundary value for a long time, and if the wind speed is larger, the rotation speed stays at the upper boundary value for a long time. As shown in fig. 6, the abnormal points are distributed in a column shape, and the maximum Ki value of the abnormal points reaches 1, that is, at some time intervals, the unit rotation speed is in the rotation avoiding interval for a long time. Therefore, according to the distribution of the avoidance speed duration ratio (i.e. a large number of abnormal points corresponding to wind speeds near the wind speed section corresponding to the avoidance speed interval (i.e. 4-9m/S) appear, and the abnormal points are distributed in a column shape, and Ki values of part of the abnormal points are large), it can be determined that the avoidance speed condition of the wind turbine generator system is caused by the limited power operation, specifically, the power of the turbine generator system is related to the rotation speed, and the higher the power corresponds to the higher the rotation speed of the turbine generator system, so that the rotation speed set value corresponding to the limited power requirement value is searched during the power limitation, and is used as the rotation speed control target, and once the rotation speed set value corresponding to the limited power requirement value is in the avoidance speed interval, the avoidance speed condition is abnormal, and therefore, the situation can be improved by executing steps S20-S30.

According to the exemplary embodiment of the invention, whether the rotation avoiding speed condition of the wind generating set is abnormal or not can be rapidly and accurately evaluated, and corresponding treatment is carried out aiming at the reason causing the abnormal rotation avoiding speed condition by further combining with root cause analysis and diagnosis, so that abnormal jumping out is realized, the normal running state of the wind generating set is returned, and further vibration overrun and load increase are avoided.

Fig. 7 shows a block diagram of a stall control device of a wind park according to an exemplary embodiment of the invention.

As shown in fig. 7, the anti-rotation speed control apparatus of a wind turbine generator set according to an exemplary embodiment of the present invention includes: a determination unit 10, a judgment unit 20, and a setting unit 30.

Specifically, the determination unit 10 is configured to determine an upper limit of a power value required by an instruction when the instruction for the limited power operation is received.

The judging unit 20 is configured to determine whether the upper limit of the requested power value is in a bypass interval corresponding to the bypass interval. The upper boundary value of the power avoiding interval is a power value determined based on the upper boundary value of the rotation avoiding interval, the lower boundary value of the power avoiding interval is a power value determined based on the lower boundary value of the rotation avoiding interval, and the rotation avoiding interval and the power avoiding interval are open intervals.

The setting unit 30 is configured to set the maximum allowable power value of the wind turbine generator system to a lower boundary value of the power avoidance interval when the wind turbine generator system is in the power avoidance interval.

As an example, when the power avoidance interval is not reached, the setting unit 30 may set the maximum allowable power value of the wind turbine generator set to the required upper power value limit.

As an example, the upper boundary value of the power avoidance interval may be a product of the upper boundary value of the speed avoidance interval and a first preset electromagnetic torque, and the lower boundary value of the power avoidance interval may be a product of the lower boundary value of the speed avoidance interval and a second preset electromagnetic torque, where the first preset electromagnetic torque is an electromagnetic torque value that needs to stay before the speed avoidance interval is crossed from a low speed to a high speed, and the second preset electromagnetic torque is an electromagnetic torque value when the wind turbine generator system reaches the lower boundary value of the speed avoidance interval.

As an example, the apparatus may further include: and an abnormality recognition unit (not shown) that recognizes whether there is an abnormality in which the wind turbine generator repeatedly passes through the rotation avoidance interval, based on statistical information that the rotation speed of the generator is in the rotation avoidance interval, wherein the determination unit 20 determines whether the requested upper limit of the power value is in the power avoidance interval corresponding to the rotation avoidance interval when there is the abnormality.

As an example, the statistical information that the rotation speed of the generator is in the idle rotation speed interval may include: and the counting time length of the rotating speed of the generator in the rotating speed avoiding interval and/or the counting times of entering the rotating speed avoiding interval.

As an example, the abnormality identification unit may determine, according to operation data of a historical operation period of the wind turbine generator system, a rotation avoiding speed duration ratio corresponding to each time interval in the historical operation period; when the total number of time intervals in which the corresponding speed avoiding duration ratio exceeds a preset standard ratio in the historical operation period exceeds a first preset number, determining that the wind generating set has an abnormality of repeatedly passing through a speed avoiding interval, wherein the speed avoiding duration ratio corresponding to each time interval is as follows: the total duration of a first preset interval with the rotating speed within the rotating speed avoiding interval in the time interval accounts for the proportion of the preset duration, wherein the length of each time interval is the preset duration.

As an example, the abnormality identification unit may determine that there is an abnormality in the wind turbine generator set that repeatedly passes through the rotation avoidance interval when the corresponding rotation avoidance time duration proportion among the historical operation periods exceeds a preset standard proportion and the total number of time intervals corresponding to the power-limited operation state exceeds a second preset number; or, the abnormality identification unit may determine that the wind turbine generator system has an abnormality of repeatedly passing through a speed avoidance interval when the corresponding speed avoidance duration proportion in the historical operating period exceeds a preset standard proportion and the total number of time intervals corresponding to a preset wind speed section exceeds a third preset number, where the preset wind speed section is a wind speed section near the wind speed section corresponding to the speed avoidance interval.

As an example, the anomaly identification unit may divide the operation data of the historical operation period into M groups of operation data at intervals of the preset duration, where each group of operation data includes: n rotating speed values of the generator are collected at N continuous sampling time points; and taking the ratio of the number of the rotating speed values in the first preset interval in the N rotating speed values of each group to N as the corresponding speed avoiding duration ratio corresponding to each time interval, wherein M is an integer larger than 1, and N is an integer larger than 1.

As an example, the preset standard proportion may be determined based on at least one of: the method comprises the steps of setting the jump-up duration required by the wind generating set to pass through a rotation avoiding interval from a low rotating speed to a high rotating speed, setting the jump-down duration required by the wind generating set to pass through the rotation avoiding interval from the high rotating speed to the low rotating speed, setting the number of times that the wind generating set can normally pass through the rotation avoiding interval within the preset duration, and setting the length of the preset duration.

As an example, the preset standard ratio may be: t is_maxI J/L, wherein T_maxIndicating the maximum value of the jump-up time length and the jump-down time length, indicating a margin coefficient by I, indicating the preset times of normally passing through a rotation avoiding speed interval in the preset time length by J, and indicating the length of the preset time length by L.

It should be understood that the specific processes performed by the anti-rotation speed control device of the wind turbine generator system according to the exemplary embodiment of the present invention have been described in detail with reference to fig. 1 to 6, and the details thereof will not be repeated herein.

It should be understood that each unit in the rotation speed avoidance control apparatus of the wind turbine generator set according to the exemplary embodiment of the present invention may be implemented as a hardware component and/or a software component. Those skilled in the art can implement the respective devices, for example, using Field Programmable Gate Arrays (FPGAs) or Application Specific Integrated Circuits (ASICs), according to the processes performed by the respective devices as defined.

In addition, an exemplary embodiment of the present invention further provides a wind turbine generator set, as shown in fig. 2, including a generator, a converter, a data acquisition module (not shown in the figure), and a controller, wherein the generator includes a stator and a rotor mechanically connected to an impeller; the converter is electrically coupled with the stator winding; the data acquisition module is configured to acquire the rotating speed of the generator; the controller is configured to set an electromagnetic torque parameter of the converter to control a current in the stator winding to control a rotational speed of the generator, the controller being configured to perform the rotational speed avoidance control method of the wind turbine generator set as described in the above exemplary embodiment. As an example, the data acquisition module may include a rotational speed sensor. In addition, the data acquisition module can be also configured to acquire information such as electromagnetic torque, ambient wind speed and the like of the wind generating set.

Exemplary embodiments of the present invention also provide a computer-readable storage medium storing a computer program which, when executed by a processor, implements the stall avoidance control method of a wind turbine generator set as described in the above exemplary embodiments. The computer readable storage medium is any data storage device that can store data which can be read by a computer system. Examples of computer-readable storage media include: read-only memory, random access memory, read-only optical disks, magnetic tapes, floppy disks, optical data storage devices, and carrier waves (such as data transmission through the internet via wired or wireless transmission paths).

Although a few exemplary embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.