Monitoring control method for icing state of blades of wind generating set

Abstract

The invention discloses a method for monitoring and controlling the icing state of blades of a wind generating set, which comprises the following operation steps: S10) when the grid-connected operation time of the wind generating set is greater than or equal to the preset operation time, starting monitoring; s20, whether the torque deviation value of the wind generating set is larger than or equal to the parameter Para1 or not is judged, and whether the duration time of the torque deviation value exceeds the parameter Para2 or not is judged; (S30) when it is found that the torque deviation value of the wind generating set is larger than or equal to the parameter Para1 and whether the duration time of the torque deviation value exceeds the parameter Para2 or not, the step (S40) is executed; s40, whether the actual blade angle is larger than or equal to the parameter Para3 or not is judged, and whether the duration time of the actual blade angle exceeds the parameter Para4 or not is judged; s50, when it is found that the actual blade angle is larger than or equal to the parameter Para3, and the duration time of the actual blade angle is larger than or equal to the parameter Para4, it is judged that the wind generating set is in the power-limited operation state at present; real-time monitoring of blade icing of the wind generating set is achieved, and the phenomenon that blade icing is misreported when the set is in an unlimited power operation state is avoided; meanwhile, no hardware sensor needs to be added, and no hardware cost is increased.

Description

Technical Field

[0001] The invention belongs to the field of wind power generation, and in particular relates to a method for monitoring and controlling the icing state of blades of a wind power generator set. Background Art

[0002] In the field of wind power generation, existing solutions usually use hardware blade ice detection sensors, or perform logical judgments in the main control application based on the temperature outside the cabin, wind speed, and the deviation between the unit's active power and theoretical power. Both of the above blade ice detection methods have problems to varying degrees: specifically, due to the influence of environmental factors of the wind turbine itself, such as rainy and snowy weather, high / low temperatures, unit vibration, etc., the blade ice detection sensor method has the disadvantages of being easily damaged and difficult to install and maintain; and the software measurement method that judges the deviation between the temperature outside the cabin, wind speed, and the unit's active power and theoretical power cannot accurately judge the wind turbine's power limit state, and there is a disadvantage of falsely reporting blade ice, causing the unit to shut down and causing a loss of wind turbine power generation.

[0003] Therefore, the applicant hopes to seek technical solutions to improve the above technical problems. Summary of the invention

[0004] In view of this, the purpose of the present invention is to propose a monitoring and control method for the icing state of wind turbine blades, which can effectively identify the limited power operation state of the wind turbine, realize real-time monitoring of icing of wind turbine blades, avoid false alarms of blade icing when the unit is in a non-limited power operation state, improve the accuracy of blade icing detection, and reduce power generation losses caused by false alarms of blade icing shutdown; at the same time, the solution provided by the present invention is completely completed by relying on the logical judgment of the control program, without the need to add hardware sensors, and without increasing hardware costs.

[0005] To this end, the technical solution adopted in the present invention is as follows: A control method for monitoring icing of blades of a wind turbine generator set comprises at least the following steps: S10) When the wind turbine generator set is connected to the grid and the operation time is greater than or equal to the preset operation time, monitoring starts; S20), judging whether the torque deviation value Torque_Diff of the wind turbine generator set is ≥ parameter Para1, and whether its duration exceeds parameter Para2; S30), when it is found that the torque deviation value Torque_Diff of the wind turbine generator set is greater than or equal to parameter Para1, and whether its duration exceeds parameter Para2, proceed to step S40); otherwise, return to step S20); S40), judging whether the actual blade angle Actual_PitchAngle is ≥ parameter Para3, and whether its duration exceeds parameter Para4; S50), when it is found that the actual blade angle Actual_PitchAngle ≥ parameter Para3, and its duration ≥ parameter Para4, it is determined that the wind turbine generator set is currently in the limited power operation state; otherwise, it is determined that the wind turbine generator set is not in the limited power operation state, and then the icing state of the blade is judged based on the temperature outside the cabin, the wind speed, and the deviation between the active power of the unit and the theoretical power; Among them, the parameter Para1 is the torque deviation threshold for power limit judgment; the parameter Para2 is the torque deviation duration for power limit judgment; the parameter Para3 is the blade angle threshold for power limit judgment; and the parameter Para4 is the blade angle duration for power limit judgment.

[0006] Preferably, the preset running time is 9-15 minutes.

[0007] Preferably, the torque deviation value Torque_Diff of the wind turbine = (torque limit Torque_Limit - actual torque value Actual_Torque) / torque limit Torque_Limit; wherein, the torque limit Torque_Limit = reference power value Power_Ref output by the control algorithm * 9550 / reference speed value Generator_speed_Ref output by the control algorithm; the control algorithm refers to the control program of the main control of the wind turbine generator set.

[0008] Preferably, the actual torque value Actual_Torque and the actual blade angle Actual_PitchAngle are both average values ​​of sampling detection within a fixed time, and the fixed time range is preferably 2-5 seconds.

[0009] Preferably, in step S50), when it is determined that the wind turbine generator set is currently in a power-limited operating state, the process returns to step S20).

[0010] Preferably, in step S50), the operation steps of judging the icing state of the blade based on the temperature outside the cabin, the wind speed, and the deviation between the active power of the unit and the theoretical power include the following: S51), when the temperature signal outside the cabin is lower than the parameter Para5, and the average wind speed value in the fixed period is greater than the preset average wind speed, blade icing detection is performed, wherein the parameter Para5 is the temperature value of blade icing; S52), when it is found that any one of the following conditions a and b is met, it is determined that the blade is in an icing state: a. The average wind speed value in the fixed period is greater than the preset average wind speed and less than parameter Para6, and the deviation between the average value of active power in the fixed period and the theoretical average value of active power in the fixed period exceeds parameter Para7; b. The average wind speed value in the fixed period is ≥ parameter Para6, and the deviation between the average value of active power in the fixed period and the theoretical average value of active power in the fixed period exceeds parameter Para8; Among them, the parameter Para6 is the rated wind speed value; the parameter Para7 is the blade icing power deviation threshold 1; and the parameter Para8 is the blade icing power deviation threshold 2.

[0011] Preferably, the parameter Para5 is set to 4-6°C; the preset average wind speed is set to 4-8m / s, more preferably 5-7m / s; and the fixed period is 18-22 seconds.

[0012] Preferably, in the step S52), the parameter Para7 is greater than the parameter Para8; wherein the parameter Para7 is preferably set to 46-55%; and the parameter Para8 is preferably set to 35-45%.

[0013] Preferably, in the step S52), the theoretical active power average value is calculated in the following manner: After converting the current wind speed value to obtain the standard air density, the dynamic power curve of the wind turbine generator set under the standard air density is queried according to the table lookup method, and the theoretical active power average value is obtained through linear conversion.

[0014] Preferably, the step S52) further includes: When any one of the following conditions a and b is found to be met and the duration exceeds the first time length, the blade icing alarm activation procedure is executed; When it is found that any one of the following conditions a and b is met and the duration exceeds the second time period, the blade icing shutdown activation procedure is executed; The first duration is preferably 2.5-3.5 minutes, and the second duration is preferably 4.5-5.5 minutes.

[0015] The present invention is based on the technology of detecting blade icing based on the temperature outside the cabin, wind speed and the deviation between the active power and theoretical power of the unit, and introduces the torque deviation value of the wind turbine and the blade angle comparison. Through the logical judgment of the torque deviation and the blade angle, the limited power operation state of the wind turbine generator set can be effectively identified, and the real-time monitoring of the icing of the blades of the wind turbine generator set can be realized, so as to avoid the false alarm of blade icing when the unit is in a non-limited power operation state, improve the accuracy of blade icing detection, and reduce the power generation loss caused by the shutdown due to the false alarm of blade icing. At the same time, the solution provided by the present invention is completely completed by relying on the logical judgment of the control program, without adding hardware sensors and without increasing hardware costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a logic flow chart of whether the wind turbine generator set is in a limited power operation state under a specific implementation mode of the present application; DETAILED DESCRIPTION

[0017] The embodiment of the present invention discloses a control method for monitoring icing of blades of a wind turbine generator set, which at least includes the following operating steps: S10) When the wind turbine generator set is connected to the grid and the operation time is greater than or equal to the preset operation time, monitoring starts; S20), judging whether the torque deviation value Torque_Diff of the wind turbine generator set is ≥ parameter Para1, and whether its duration exceeds parameter Para2; S30), when it is found that the torque deviation value Torque_Diff of the wind turbine generator set is greater than or equal to parameter Para1, and whether its duration exceeds parameter Para2, proceed to step S40); otherwise, return to step S20); S40), judging whether the actual blade angle Actual_PitchAngle is ≥ parameter Para3, and whether its duration exceeds parameter Para4; S50), when it is found that the actual blade angle Actual_PitchAngle ≥ parameter Para3, and its duration ≥ parameter Para4, it is determined that the wind turbine generator set is currently in the limited power operation state; otherwise, it is determined that the wind turbine generator set is not in the limited power operation state, and then the icing state of the blade is judged based on the temperature outside the cabin, the wind speed, and the deviation between the active power of the unit and the theoretical power; Among them, parameter Para1 is the torque deviation threshold for power limit judgment; parameter Para2 is the torque deviation duration for power limit judgment; parameter Para3 is the blade angle threshold for power limit judgment; parameter Para4 is the blade angle duration for power limit judgment.

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] This embodiment provides a control method for monitoring icing of blades of a wind turbine generator set, comprising the following steps: S10), please refer to Figure 1 As shown, when the wind turbine (referred to as "wind turbine") grid-connected operation time is greater than or equal to the preset operation time, monitoring starts; preferably, the preset operation time is 9-15 minutes; specifically preferably, in this embodiment, the preset operation time is 10 minutes (min); S20), determine whether the torque deviation value Torque_Diff of the wind turbine generator set is ≥ parameter Para1, and whether its duration exceeds parameter Para2; wherein parameter Para1 is the torque deviation threshold for power limit judgment; parameter Para2 is the torque deviation duration for power limit judgment; preferably, in this embodiment, the torque deviation value Torque_Diff of the wind turbine = (torque limit Torque_Limit-actual torque value Actual_Torque) / torque limit Torque_Limit; wherein the torque limit Torque_Limit (that is, Figure 1 The "control algorithm output torque limit value" shown in the figure) = the reference power value Power_Ref output by the control algorithm * 9550 / the reference speed value Generator_speed_Ref output by the control algorithm; the control algorithm refers to the control program of the main control of the wind turbine generator set; S30), when it is found that the torque deviation value Torque_Diff of the wind turbine generator set is greater than or equal to parameter Para1, and whether its duration exceeds parameter Para2, proceed to step S40); otherwise, return to step S20); S40), determine whether the actual blade angle Actual_PitchAngle is ≥ parameter Para3, and whether its duration exceeds parameter Para4; wherein parameter Para3 is the blade angle threshold for power limit determination; parameter Para4 is the blade angle duration for power limit determination; S50), when it is found that the actual blade angle Actual_PitchAngle ≥ parameter Para3, and its duration ≥ parameter Para4, it is determined that the wind turbine generator set is currently in a limited power operation state, that is, Figure 1Otherwise, it is determined that the wind turbine generator set is not in the power-limited operation state. Figure 1 The "power limit state is activated" shown in the figure, and then the icing state of the blades is judged based on the temperature outside the cabin, the wind speed, and the deviation between the unit's active power and the theoretical power; Preferably, in this embodiment, the actual torque value Actual_Torque and the actual blade angle Actual_PitchAngle are both average values ​​of sampling detection within a fixed time, and the fixed time range is preferably 2-5 seconds; specifically preferably, in this embodiment, the fixed time is 3 seconds; Preferably, in step S50) of this embodiment, when it is determined that the wind turbine generator set is currently in a power-limited operating state, the process returns to step S20) to continue detecting and judging the power-limited state; Preferably, in step S50) of this embodiment, the operation steps of judging the icing state of the blade based on the temperature outside the cabin, the wind speed, and the deviation between the active power of the unit and the theoretical power include the following: S51), when the temperature signal outside the cabin is lower than the parameter Para5, and the average wind speed value in the fixed period is greater than the preset average wind speed, blade icing detection is performed, wherein the parameter Para5 is the temperature value of blade icing; preferably, in this embodiment, the parameter Para5 is set to 4-6°C; the preset average wind speed is set to 4-8m / s, more preferably 5-7m / s; the fixed period is 18-22 seconds; specifically preferably, in this embodiment, the parameter Para5 is set to 5°C; the preset average wind speed is set to 6m / s; the fixed period is 20 seconds; S52), when it is found that any one of the following conditions a and b is met, it is determined that the blade is in an icing state: a. The average wind speed value in the fixed period is greater than the preset average wind speed and less than parameter Para6, and the deviation between the average active power value in the fixed period and the theoretical average active power value in the fixed period exceeds parameter Para7; wherein parameter Para6 is the rated wind speed value; parameter Para7 is the blade icing power deviation threshold 1; b. The average wind speed value in the fixed period is ≥ parameter Para6, and the deviation between the average value of active power in the fixed period and the average value of theoretical active power in the fixed period exceeds parameter Para8; wherein parameter Para8 is blade icing power deviation threshold 2; Preferably, in this step S52), the theoretical active power average value is calculated by the following method: After converting the current wind speed value to the standard air density, the dynamic power curve of the wind turbine generator set under the standard air density is queried according to the table lookup method, and the theoretical active power average value is obtained through linear conversion.

[0020] Preferably, in this step S52), parameter Para7 is greater than parameter Para8; wherein parameter Para7 is preferably set to 46-55%, specifically, in this embodiment, parameter Para7 is set to 50%; parameter Para8 is preferably set to 35-45%, specifically, in this embodiment, parameter Para7 is set to 40%; Preferably, in this step S52), when it is found that any one of the following conditions a and b is met and its duration exceeds the first time length, the blade icing alarm activation procedure is executed; when it is found that any one of the following conditions a and b is met and its duration exceeds the second time length, the blade icing shutdown activation procedure is executed; the first time length is preferably 2.5-3.5 minutes, and the second time length is preferably 4.5-5.5 minutes; specifically preferably, in this embodiment, the first time length is set to 3 minutes, and the second time length is set to 5 minutes.

[0021] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0022] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A control method for monitoring icing of blades of a wind turbine generator set, characterized in that: At least the following steps are included: S10) When the wind turbine generator set is connected to the grid and the operation time is greater than or equal to the preset operation time, monitoring starts; S20), judging whether the torque deviation value Torque_Diff of the wind turbine generator set is ≥ parameter Para1, and whether its duration exceeds parameter Para2; S30), when it is found that the torque deviation value Torque_Diff of the wind turbine generator set is greater than or equal to parameter Para1, and whether its duration exceeds parameter Para2, proceed to step S40); otherwise, return to step S20); S40), judging whether the actual blade angle Actual_PitchAngle is ≥ parameter Para3, and whether its duration exceeds parameter Para4; S50), when it is found that the actual blade angle Actual_PitchAngle ≥ parameter Para3, and its duration ≥ parameter Para4, it is determined that the wind turbine generator set is currently in the limited power operation state; otherwise, it is determined that the wind turbine generator set is not in the limited power operation state, and then the icing state of the blade is judged based on the temperature outside the cabin, the wind speed, and the deviation between the active power of the unit and the theoretical power; Among them, the parameter Para1 is the torque deviation threshold for power limit judgment; the parameter Para2 is the torque deviation duration for power limit judgment; the parameter Para3 is the blade angle threshold for power limit judgment; and the parameter Para4 is the blade angle duration for power limit judgment.

2. The control method for monitoring icing of blades of a wind turbine generator set according to claim 1, characterized in that: The preset running time is 9-15 minutes.

3. The control method for monitoring icing of blades of a wind turbine generator set according to claim 1, characterized in that: The torque deviation value Torque_Diff of the wind turbine = (torque limit Torque_Limit - actual torque value Actual_Torque) / torque limit Torque_Limit; wherein, the torque limit Torque_Limit = reference power value Power_Ref output by the control algorithm * 9550 / reference speed value Generator_speed_Ref output by the control algorithm; the control algorithm refers to the control program of the main control of the wind turbine generator set.

4. The control method for monitoring icing of blades of a wind turbine generator set according to claim 3, characterized in that: The actual torque value Actual_Torque and the actual blade angle Actual_PitchAngle are both average values ​​of sampling detection within a fixed time, and the fixed time range is preferably 2-5 seconds.

5. The control method for monitoring icing of blades of a wind turbine generator set according to claim 1, characterized in that: In the step S50), when it is determined that the wind turbine generator set is currently in the power-limited operation state, the process returns to step S20).

6. The control method for monitoring icing of blades of a wind turbine generator set according to claim 1, characterized in that: In step S50), the operation steps of judging the icing state of the blade based on the temperature outside the cabin, the wind speed, and the deviation between the active power of the unit and the theoretical power include the following: S51), when the temperature signal outside the cabin is lower than the parameter Para5, and the average wind speed value in the fixed period is greater than the preset average wind speed, blade icing detection is performed, wherein the parameter Para5 is the temperature value of blade icing; S52), when it is found that any one of the following conditions a and b is met, it is determined that the blade is in an icing state: a. The average wind speed value in the fixed period is greater than the preset average wind speed and less than parameter Para6, and the deviation between the average value of active power in the fixed period and the theoretical average value of active power in the fixed period exceeds parameter Para7; b. The average wind speed value in the fixed period is ≥ parameter Para6, and the deviation between the average value of active power in the fixed period and the theoretical average value of active power in the fixed period exceeds parameter Para8; Among them, the parameter Para6 is the rated wind speed value; the parameter Para7 is the blade icing power deviation threshold 1; and the parameter Para8 is the blade icing power deviation threshold 2.

7. The control method for monitoring icing of blades of a wind turbine generator set according to claim 6, characterized in that: The parameter Para5 is set to 4-6°C; the preset average wind speed is set to 4-8m / s, more preferably 5-7m / s; and the fixed period is 18-22 seconds.

8. The control method for monitoring icing of blades of a wind turbine generator set according to claim 6, characterized in that: In the step S52), the parameter Para7 is greater than the parameter Para8; wherein the parameter Para7 is preferably set to 46-55%; and the parameter Para8 is preferably set to 35-45%.

9. The control method for monitoring icing of blades of a wind turbine generator set according to claim 6, characterized in that: In the step S52), the theoretical active power average value is calculated in the following manner: After converting the current wind speed value to obtain the standard air density, the dynamic power curve of the wind turbine generator set under the standard air density is queried according to the table lookup method, and the theoretical active power average value is obtained through linear conversion.

10. The control method for monitoring icing of blades of a wind turbine generator set according to claim 6, characterized in that: The step S52) further includes: When any one of the following conditions a and b is found to be met and the duration exceeds the first time length, the blade icing alarm activation procedure is executed; When it is found that any one of the following conditions a and b is met and the duration exceeds the second time period, the blade icing shutdown activation procedure is executed; The first duration is preferably 2.5-3.5 minutes, and the second duration is preferably 4.5-5.5 minutes.

Images