Power control method and equipment for wind power plant and medium

Abstract

The invention discloses a power control method and device for a wind power plant and a medium, and belongs to the field of wind power generation. The method comprises the following steps: obtaining compensation power for improving power according to grid-connected power and limit grid-connected power of a wind power plant; based on the wind parameters of the first target wind turbine generator in the wind power plant in the undernormal state and the wind parameters of the first target wind turbine generator in the historical duration, the wind parameter load relation parameters and a preset simulation load database, determining a second target wind turbine generator of which the redundancy margin damage is greater than the override accumulated damage in the first target wind turbine generator; and based on the compensation power, the current power of the second target wind turbine generator, the current wind parameter, the wind parameter load relation parameter and a simulation load database, controlling at least part of the second target wind turbine generator to operate in an overrunning state. According to the embodiment of the invention, the output efficiency of the wind power plant can be improved, and the wind energy utilization rate of the wind power plant is improved.

Description

Technical Field

[0001] The present application relates to the field of wind power generation, and in particular to a power control method, device and medium for a wind farm. Background Art

[0002] There are multiple wind turbines installed in a wind farm, which can convert wind energy into electrical energy on a large scale. Under normal circumstances, wind turbines are usually controlled to operate in a normal state, but when the power grid is unstable or affected by other factors, it is necessary to control the wind turbines to operate at a reduced power or shut down. The changes in the operating state of wind turbines caused by various factors make it difficult for the wind farm's grid-connected power to reach the wind farm's limit grid-connected power, reducing the output efficiency of wind turbines in the wind farm and also reducing the utilization rate of wind energy. Summary of the invention

[0003] The embodiments of the present application provide a power control method, device and medium for a wind farm, which can improve the output efficiency of the wind farm and increase the utilization rate of wind energy in the wind farm.

[0004] In a first aspect, an embodiment of the present application provides a power control method for a wind farm, comprising: obtaining compensation power for increasing power according to the grid-connected power and the limit grid-connected power of the wind farm; determining a second target wind turbine group whose redundant margin damage is greater than the cumulative damage of over-generation in the first target wind turbine group based on the wind parameters of the first target wind turbine group in the wind farm in a subnormal state within a historical period, the wind parameters in an over-generation state, as well as wind parameter-load relationship parameters and a preset simulation load database; and controlling at least part of the second target wind turbine group to operate in the over-generation state based on the compensation power, the current power of the second target wind turbine group, the current wind parameters, the wind parameter-load relationship parameters and the simulation load database.

[0005] In some possible embodiments, based on the wind parameters of the first target wind turbine in the wind farm in a subnormal state within a historical period of time, the wind parameters in the overgeneration state, the wind parameter-load relationship parameters and a preset simulation load database, a second target wind turbine whose redundant margin damage is greater than the overgeneration cumulative damage is determined in the first target wind turbine, including: based on the wind parameters in the subnormal state and the wind parameter-load relationship parameters, obtaining the first time load data in the subnormal state and the second time load data in the normal state in the simulation load database; based on the wind parameters in the overgeneration state and the wind parameter-load relationship parameters, obtaining the third time load data in the overgeneration state in the simulation load database; according to the first time load data, the second time load data and the third time load data, obtaining the redundant margin damage and the overgeneration cumulative damage of the first target wind turbine; according to the redundant margin damage and the overgeneration cumulative damage of the first target wind turbine, determining the second target wind turbine.

[0006] In some possible embodiments, the wind parameter-load relationship parameters include wind parameter-load influence parameters and wind parameter-load trend relationship parameters; based on the wind parameters in the less-normal state and the wind parameter-load relationship parameters, the first time load data in the less-normal state and the second time load data in the normal state are obtained in the simulation load database, including: calculating the similarity distance between the wind parameters in the less-normal state and the wind parameters in the simulation load database according to the wind parameters in the less-normal state, the wind parameter load influence parameters and the wind parameters in the simulation load database; according to the principle of close similarity distance, the time load data of the wind parameters in the less-normal state in the simulation load database that satisfy the wind parameter-load trend relationship parameters with the wind parameters in the less-normal state is determined as the first time load data; according to the principle of close similarity distance, the time load data of the wind parameters in the simulation load database that satisfy the wind parameter-load trend relationship parameters with the wind parameters in the normal state is determined as the second time load data.

[0007] In some possible embodiments, redundant margin damage and over-generation cumulative damage of the first target wind turbine group are obtained based on first time load data, second time load data and third time load data, including: obtaining first amplitude frequency data corresponding to the first time load data and second amplitude frequency data corresponding to the second time load data based on the first time load data and the second time load data; determining redundant margin damage based on the difference between the second amplitude frequency data and the first amplitude frequency data; obtaining third amplitude frequency data corresponding to the third time load data based on the third time load data, and determining it as over-generation cumulative damage.

[0008] In some possible embodiments, based on the compensation power, the current power of the second target wind turbine group, the current wind parameters, the wind-parameter-load relationship parameters and the simulation load database, at least part of the second target wind turbine groups are controlled to operate in an over-generation state, including: selecting a third target wind turbine group from the second target wind turbine groups whose damage difference between the redundant margin damage and the over-generation cumulative damage meets a predetermined condition; obtaining a temporary over-generation power of the third target wind turbine group based on the current power and the compensation power of the third target wind turbine group; predicting the expected over-generation damage of the third target wind turbine group based on the current wind parameters, the temporary over-generation power, the wind-parameter-load relationship parameters and the simulation load database; determining the over-generation power of the third target wind turbine group based on the expected over-generation damage and the damage difference of the third target wind turbine group, and controlling the third target wind turbine group according to the over-generation power.

[0009] In some possible embodiments, based on current wind parameters, temporary over-generation power, wind-parameter-load relationship parameters and a simulation load database, the expected over-generation damage of the third target wind turbine is predicted, including: based on the current wind parameters, temporary over-generation power, wind-parameter-load relationship parameters, obtaining fourth time load data under temporary over-generation power in the simulation load database; based on the fourth time load data, predicting the expected over-generation damage of the third target wind turbine.

[0010] In some possible embodiments, the wind parameter-load relationship parameters include wind parameter-load influence parameters and wind parameter-load trend relationship parameters; based on the current wind parameters, temporary over-generation power, and wind parameter-load relationship parameters, the fourth time load data under temporary over-generation power is obtained in the simulation load database, including: calculating the similarity distance between the current wind parameters and the wind parameters in the simulation load database according to the current wind parameters, the wind parameter load influence parameters, and the wind parameters in the simulation load database; according to the principle of close similarity distance, the time load data of the wind parameters in the simulation load database under temporary over-generation power that meet the wind parameter load trend relationship parameters with the current wind parameters and whose limit load is less than the predetermined safety load is determined as the fourth time load data.

[0011] In some possible embodiments, the over-generation power of the third target wind turbine is determined based on the difference in damage between the expected over-generation damage and the third target wind turbine, including: if the expected over-generation damage is less than or equal to the damage difference, determining the temporary over-generation power as the over-generation power; if the expected over-generation damage is greater than the damage difference, reducing the temporary over-generation power; based on the current wind parameters, the reduced temporary over-generation power, the wind-parameter-load relationship parameters and the simulation load database, re-predicting the expected over-generation damage of the third target wind turbine until the expected over-generation damage is less than or equal to the damage difference, and determining the reduced temporary over-generation power as the over-generation power.

[0012] In some possible embodiments, the simulation load database includes time load data simulated under different wind parameters, different unit power states, and different wind turbine component conditions; the method also includes: obtaining an equivalent fatigue load corresponding to the time load data based on the time load data in the simulation load database; using the corresponding wind parameters and time load data in the simulation load database, as well as the corresponding time load data and equivalent fatigue load, to calculate the linear relationship parameters between the wind parameters and the equivalent fatigue load; based on the linear relationship parameters, obtaining the wind parameter-load relationship parameters.

[0013] In some possible embodiments, after controlling at least part of the second target wind turbines to operate in an over-generation state, it also includes: updating the grid-connected power of the wind farm; if the updated grid-connected power is less than the limit grid-connected power, obtaining a new compensation power based on the updated grid-connected power and the limit grid-connected power, and redetermining the second target wind turbines.

[0014] In some possible embodiments, the redundant margin damage of the second target wind turbine group includes the redundant margin damage of the wind turbine components in the second target wind turbine group, and the over-generation cumulative damage of the second target wind turbine group includes the over-generation cumulative damage of the wind turbine components in the second target wind turbine group; the method also includes: when the second target wind turbine group is operating in an over-generation state, if the difference between the redundant margin damage and the over-generation cumulative damage of any wind turbine component in the second target wind turbine group meets the control switching condition, then the second target wind turbine group is controlled to operate in a normal state or in a less-than-normal state.

[0015] In some possible embodiments, the first target wind turbine group includes a wind turbine group whose wind speed is higher than the rated wind speed of the group; the method also includes: when the second target wind turbine group is operating in an over-generation state, if the wind speed is less than or equal to the rated wind speed of the group, controlling the second target wind turbine group to operate in a normal state or in a less-than-normal state.

[0016] In a second aspect, an embodiment of the present application provides a power control device for a wind farm, comprising: a processor and a memory storing computer program instructions; when the processor executes the computer program instructions, the power control method for the wind farm of the first aspect is implemented.

[0017] In a third aspect, an embodiment of the present application provides a computer-readable storage medium, on which computer program instructions are stored. When the computer program instructions are executed by a processor, the power control method of the wind farm of the first aspect is implemented.

[0018] The embodiment of the present application provides a power control method, device and medium for a wind farm. Based on the wind parameters of the wind turbines in the wind farm in the historical time period in the subnormal state, the wind parameters in the over-generation state and the wind parameter load relationship parameters, the redundant margin damage and the over-generation cumulative damage of the wind turbines are obtained by using the time load data in the simulation load database. The redundant margin damage of the wind turbine is greater than the over-generation cumulative damage, indicating that the wind turbine still has spare power to operate in the over-generation state. Based on the current power of the wind turbine, the current wind parameters and the wind parameter load relationship parameters, the simulation load data, and the compensation power that the wind farm can increase from the grid-connected power to the limit grid-connected power, the wind turbines that still have spare power to operate in the over-generation state are controlled to operate in the over-generation state. Within the safety range of the damage of the wind turbine, the damage that is still acceptable in the historical time period is converted into the expected damage of over-generation in the future, and the acceptable damage and the damage that have been borne at each stage of the wind turbine are balanced, so as to avoid the over-generation state from having an adverse effect on the life and reliability of the wind turbine, and at the same time improve the output efficiency of the wind turbine and the wind farm, and improve the utilization rate of wind energy in the wind farm. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0020] Figure 1 A flow chart of a wind farm power control method provided in one embodiment of the present application;

[0021] Figure 2 A flow chart of a wind farm power control method provided by another embodiment of the present application;

[0022] Figure 3 A deviation frequency histogram of an example of an equivalent fatigue load and an actual fatigue load of a fixed hub provided in an embodiment of the present application;

[0023] Figure 4 A flow chart of a wind farm power control method provided in yet another embodiment of the present application;

[0024] Figure 5 A schematic diagram of the structure of a power control device for a wind farm provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0026] There are multiple wind turbines installed in a wind farm, which can convert wind energy into electrical energy on a large scale. Under normal circumstances, wind turbines are usually controlled to operate in a normal state, but when the power grid is unstable or affected by other factors, it is necessary to control the wind turbines to operate at a reduced power or shut down. The changes in the operating state of wind turbines caused by various factors make it difficult for the wind farm's grid-connected power to reach the wind farm's limit grid-connected power, reducing the output efficiency of wind turbines in the wind farm and also reducing the utilization rate of wind energy.

[0027] In order to improve the output efficiency of wind turbines in wind farms and increase the utilization rate of wind energy, wind turbines can be operated in an over-generation state, that is, operated beyond the rated power, to recover some of the power that has not reached the limit grid-connected power. However, the operation of wind turbines beyond the rated power may have an adverse effect on the life and reliability of wind turbines. Therefore, while pursuing the operation of wind turbines in an over-generation state, it is also necessary to ensure the safety and reliability of wind turbines.

[0028] The embodiments of the present application provide a power control method, device and medium for a wind farm, which can judge the historical accumulated damage already suffered and the historical accumulated acceptable damage of the wind turbine based on the wind parameters of the wind turbines in the wind farm in a subnormal state, a normal state and an over-generation state, using a simulation load database that pre-sets the correspondence between wind parameters, unit power states and time load data, and according to the historical accumulated damage already suffered and the historical accumulated acceptable damage, convert the historical accumulated redundant acceptable damage into the damage suffered by the wind turbine in an over-generation state in a future period of time, thereby ensuring that the wind turbine will not suffer excessive damage, and on the basis of ensuring the safety of the wind turbine, improve the output efficiency of the wind turbine, thereby improving the utilization rate of wind energy.

[0029] The power control method, device and medium of the wind farm provided in the present application are described below respectively.

[0030] A first aspect of the present application provides a power control method for a wind farm. The power control method for a wind farm can be executed by a power control device, equipment, etc. of the wind farm, and is not limited herein. Figure 1 A flow chart of a wind farm power control method provided in an embodiment of the present application is shown in FIG. Figure 1 As shown, the power control method of the wind farm may include steps S101 to S103.

[0031] In step S101, a compensation power for increasing power is obtained according to the grid-connected power and the limit grid-connected power of the wind farm.

[0032] The grid-connected power of a wind farm is the actual grid-connected power of the wind farm. The limit grid-connected power of a wind farm is the maximum grid-connected power that the wind farm can execute. The grid-connected power is less than or equal to the limit grid-connected power. Specifically, the difference between the limit grid-connected power and the grid-connected power can be determined as the compensation power. The compensation power can be used to increase the grid-connected power of the wind farm. The increased grid-connected power is less than or equal to the limit grid-connected power.

[0033] In step S102, based on the wind parameters of the first target wind turbine group in the wind farm in a subnormal state within a historical period, the wind parameters in an overgeneration state, the wind parameter-load relationship parameters and a preset simulation load database, a second target wind turbine group whose redundant margin damage is greater than the cumulative damage of overgeneration is determined in the first target wind turbine group.

[0034] The subnormal state includes the shutdown state and the power-limited state. The power of the wind turbine in the subnormal state will be lower than the power in the normal state. The wind turbine in the subnormal state will produce some power generation loss. In some examples, the power-limited state can be divided into multiple power-limited states according to the power size of the wind turbine. For example, the power of the wind turbine in the normal state, that is, the normal power, is P, then the power of the wind turbine in multiple power-limited states can be 99% P, 98% P, ..., low% P, and low% is the ratio of the minimum power in the power-limited state to the normal power. The over-generation state is an operating state in which the power of the wind turbine is higher than the power in the normal state. In some examples, the over-generation state can be divided into multiple over-generation states according to the power size of the wind turbine. For example, the power of the wind turbine in the normal state, that is, the normal power, is P, then the power of the wind turbine in multiple over-generation states can be 101% P, 102% P, ..., high% P, and high% is the ratio of the maximum power in the over-generation state to the normal power. In some examples, the power of the wind turbine in the normal state, that is, the normal power, can be the rated power of the wind turbine. What is obtained here is the wind parameters of the first target wind turbine group in the wind farm that is in an under-normal state within a historical period and the wind parameters of the first target wind turbine group that is in an over-generation state within a historical period.

[0035] Wind parameters are used to characterize the state of wind resources. In some examples, wind parameters may include, but are not limited to, one or more of air density, wind speed, wind shear coefficient, inflow angle, turbulence intensity, and the like.

[0036] The wind parameter load relationship parameter can characterize the relationship between the wind parameter and the load of the wind turbine set. The load of the wind turbine set may include an equivalent fatigue load, which can be regarded as a fatigue load. In some examples, the load of the wind turbine set includes the load of the wind turbine components in the wind turbine set, and the wind parameter load relationship can characterize the relationship between the wind parameter and the load of the wind turbine components in the wind turbine set. The relationship between the wind parameter and the load of the wind turbine set may include the importance of the influence of the wind parameter on the load, and the relationship between the change of the wind parameter and the change of the load of the wind turbine set. In some examples, the wind parameter load relationship parameter may include a wind parameter load influence parameter and a wind parameter load trend relationship parameter. The wind parameter load influence parameter characterizes the importance of the influence of the wind parameter on the equivalent fatigue load, and the wind parameter load trend relationship parameter characterizes the relationship between the change of the wind parameter and the change of the equivalent fatigue load. For example, the wind parameter load influence parameter can be implemented as the influence weight of the wind parameter on the load, and the wind parameter load trend relationship parameter can be implemented as a parameter characterizing whether the wind parameter is positively correlated or negatively correlated with the load.

[0037] The simulation load database includes time load data obtained by simulating the wind turbine. The time load data can reflect the corresponding relationship between time and load, such as equivalent fatigue load, that is, it can reflect the development of load over time. In some examples, the time load data can be implemented as a sequence or matrix for easy calculation. For example, a unit time Ts can be set, and the load corresponding to the wind parameter at a time point in each unit time Ts can form a time load data. In some examples, the simulation load database may include time load data simulated under different wind parameters, different unit power states, and different wind turbine components. The unit power state may include an abnormal state, a normal state, and an over-generation state. The load in the time load data is related to the wind parameters, the unit power state, and the wind turbine components. The corresponding time load data can be obtained by simulating wind turbine components with different wind parameters and different unit power states. In each unit power state, multiple groups of wind parameters can be input for simulation calculation to obtain time load data. There can be a one-to-many relationship between the unit power state and the time load data. For example, the i-th group of wind parameters is recorded as w i , multiple sets of wind parameters can be obtained as shown in the following formula (1). Each unit power state can correspond to multiple sets of wind parameters, thereby generating multiple time load data as shown in the following formula (2):

[0038]

[0039]

[0040] Among them, ρ is air density, and different subscripts represent air density in different groups of wind parameters; vave is wind speed, and different subscripts represent wind speed in different groups of wind parameters; shear is wind shear coefficient, and different subscripts represent wind shear coefficient in different groups of wind parameters; inflow is inflow angle, and different subscripts represent inflow angle in different groups of wind parameters; turbulence is turbulence intensity, and different subscripts represent turbulence intensity in different groups of wind parameters; w is wind parameter, and different subscripts represent wind parameters in different groups; P0 represents shutdown state, and the corresponding Load 0i is the time load data obtained by simulating the i-th group of wind parameters in the shutdown state; P low％ Indicates the power limit state, the corresponding Load low％i is the time load data obtained by simulating the i-th group of wind parameters under the power reduction state. If the power reduction state is divided into multiple specific power states, then each power reduction state corresponding to each power has a corresponding time load data; P represents the normal state, and the corresponding Load i is the time load data obtained by simulating the i-th group of wind parameters under normal conditions; P high％ Indicates the over-issuance state, the corresponding Load high％i is the time load data obtained by simulating the i-th group of wind parameters under the over-generation state. If the over-generation state is divided into multiple specific power states, then each over-generation state corresponding to each power has a corresponding time load data.

[0041] If at least one of the wind parameters, unit power state and wind turbine components is different, the obtained time load data may be different. For example, the time load data obtained under the same unit power state, the same wind turbine components but different wind parameters may be different, and the time load data obtained under different unit power states, the same wind turbine components and the same wind parameters may also be different, which are not listed here one by one.

[0042] The first target wind turbine group may include at least some of the wind turbine groups in the wind farm. In some examples, a wind turbine group with relatively better wind conditions in the wind farm may be selected as the first target wind turbine group, such as a wind turbine group with a wind speed higher than the rated wind speed of the unit. Wind turbine groups under the rated wind speed of the unit can operate at the rated power of the unit. In order to improve the processing efficiency of the wind turbine group, some wind turbine groups may be controlled to operate in an over-generation state. If the wind turbine group wants to operate in an over-generation state, it is necessary to have suitable wind conditions as support. Only when the wind speed is higher than the rated wind speed of the unit can the wind turbine group be able to operate in an over-generation state. The first target wind turbine group can be screened in the wind farm by the condition that the wind speed is greater than the rated wind speed of the unit. The first target wind turbine group has the conditions to operate in an over-generation state, but it is also necessary to ensure that the wind turbine group operating in an over-generation state can operate safely. At least some of the first target wind turbine groups can be selected as the second target wind turbine groups through the redundant margin damage and over-generation cumulative damage of the first target wind turbine group in the historical time length. The second target wind turbine sets include the first target wind turbine sets whose redundant margin damage within the historical time period is greater than the accumulated damage of over-generation.

[0043] The redundant margin damage of the first target wind turbine generator set can be obtained based on the wind parameters of the first target wind turbine generator set in the less-normal state in the historical time length, the wind parameter-load relationship parameters and the simulation load database, which can be regarded as the redundant damage accumulated by the first target wind turbine generator set after the less-normal state in the historical time length, and the damage that can continue to be borne after the less-normal state in the historical time length. The time load data in the simulation load database is the time load data corresponding to the wind parameters and the power state of the unit. The time load data corresponding to the wind parameters in the less-normal state can be obtained in the simulation load database according to the wind parameters in the less-normal state and the wind parameter-load relationship parameters, and then the amplitude frequency data is converted according to the time load data corresponding to the wind parameters in the less-normal state, and the redundant margin damage is obtained according to the amplitude frequency data. The over-generation cumulative damage of the first target wind turbine generator set can be obtained based on the wind parameters of the first target wind turbine generator set in the over-generation state in the historical time length, the wind parameter-load relationship parameters and the simulation load database, which can be regarded as the accumulated damage suffered by the first target wind turbine generator set in the over-generation state in the historical time length. According to the wind parameters in the over-generation state and the wind parameter-load relationship parameters, the time load data corresponding to the wind parameters in the over-generation state can be obtained in the simulation load database, and then the amplitude frequency data can be converted according to the time load data corresponding to the wind parameters in the over-generation state, and the over-generation cumulative damage can be obtained according to the amplitude frequency data. The amplitude frequency data will be described in detail later. For ease of understanding, the damage is described here. The amplitude frequency data corresponding to the time load data can be obtained by counting the rain flow of the time load data. The amplitude frequency data can be specifically implemented as an amplitude frequency matrix. The amplitude cycle number in the amplitude frequency matrix can be accumulated. The fatigue damage of the material can usually be regarded as the cumulative damage under cyclic loading. The above conclusion can be obtained based on the linear fatigue damage accumulation (i.e. Palmgren-Miner) assumption. Therefore, the cumulative damage, residual damage or expected damage can be obtained by converting the time load data in the Founder load database. Redundant residual damage is the damage that the wind turbine has spare power to accept. The over-generation cumulative damage is the damage that the wind turbine has already suffered in the over-generation state. If the wind turbine is to be able to operate safely, the over-generation cumulative damage of the wind turbine cannot exceed the redundant margin damage. Therefore, the first target wind turbine whose redundant margin damage is greater than the over-generation cumulative damage is selected as the second target wind turbine. It should be noted that the redundant margin damage of the wind turbine includes the redundant margin damage of the wind turbine components in the wind turbine, the over-generation cumulative damage of the wind turbine includes the over-generation cumulative damage of the wind turbine components in the wind turbine, and the redundant margin damage of the wind turbine is greater than the over-generation cumulative damage means that the redundant margin damage of each wind turbine component in the wind turbine is greater than the over-generation cumulative damage. For example, the selection of the second target wind turbine must satisfy the following formula (3):

[0044]

[0045] Where C represents the difference between the redundant margin damage of the wind turbine and the cumulative damage of overproduction, i.e., the difference; F no_ck is the redundancy margin damage of the kth wind turbine component in the wind turbine; F phighk is the over-generation cumulative damage of the kth wind turbine component in the wind turbine.

[0046] In step S103, based on the compensation power, the current power of the second target wind turbine group, the current wind parameters, the wind-parameter-load relationship parameters and the simulation load database, at least part of the second target wind turbine group is controlled to operate in an over-generation state.

[0047] The current power of the second target wind turbine group may be the actual power of the second target wind turbine group at a certain time during the power control process. The current wind parameter may be the wind parameter at a certain time during the power control process. It should be noted that the current power and the current wind parameter of the second target wind turbine group are obtained in groups, and the acquisition time corresponding to the current power of the same group of second target wind turbine groups is the same as the acquisition time of the current wind parameter. According to the current power, the current wind parameter, the wind parameter-load relationship parameter and the simulation load database, the expected damage of the second target wind turbine group in the future period can be predicted. According to the redundant margin damage and the accumulated damage of the over-generation in the historical duration of the wind turbine group, the damage that is acceptable in the historical duration of the wind turbine group can be obtained. According to the predicted expected damage of the over-generation of the second target wind turbine group in the future period and the acceptable damage in the historical duration of the wind turbine group, the over-generation power of the second target wind turbine group operating in the over-generation state is determined by using the compensation power and the current power, so as to convert the acceptable damage in the historical duration into the expected damage of over-generation in the future within a safe range, and improve the output efficiency of the wind turbine group and the wind farm on the premise of ensuring the safety of the wind turbine group and the wind farm.

[0048] Controlling the wind turbine to operate in an over-generation state and in a power-limited state requires controlling the subsystem of the wind turbine. For example, the speed or torque of the wind turbine can be adjusted by the frequency converter, thereby controlling the wind volume and wind pressure to achieve power regulation; the frequency can be increased when the power is increased, and the frequency can be reduced when the power is reduced; the blade angle can also be increased to capture more wind power to increase power, and the blade angle can be reduced to reduce the amount of wind captured, thereby limiting power.

[0049] In the embodiment of the present application, based on the wind parameters of the wind turbines in the wind farm in the historical time length in the subnormal state, the wind parameters in the over-generation state, and the wind parameter load relationship parameters, the redundant margin damage and the over-generation cumulative damage of the wind turbines are obtained by using the time load data in the simulation load database. The redundant margin damage of the wind turbine is greater than the over-generation cumulative damage, indicating that the wind turbine still has spare power to operate in the over-generation state. Based on the current power of the wind turbine, the current wind parameters and the wind parameter load relationship parameters, the simulation load data, and the compensation power that the wind farm can increase from the grid-connected power to the limit grid-connected power, the wind turbines that still have spare power to operate in the over-generation state are controlled to operate in the over-generation state. Within the safety range of the damage of the wind turbine, the damage that is still acceptable in the historical time length is converted into the expected damage of over-generation in the future, and the acceptable damage and the damage that have been borne at each stage of the wind turbine are balanced to avoid the adverse effects of the over-generation state on the life and reliability of the wind turbine, while improving the output efficiency of the wind turbine and the wind farm, and improving the utilization rate of wind energy in the wind farm. Moreover, in the process of obtaining redundant margin damage, over-generation cumulative damage, over-generation predicted damage, etc. of the wind turbine generator set in the embodiment of the present application, the time accuracy of redundant margin damage, over-generation cumulative damage, over-generation predicted damage, etc. can be flexibly adjusted through the time unit of the time load data in the simulation load database. There is no need to install load sensors on the wind turbine generator set, nor is there any need to maintain the load sensors. This can reduce the cost of wind farm power control and simplify the maintenance process of the wind turbine generator set.

[0050] In some embodiments, time load data corresponding to wind parameters and unit power status can be obtained from a simulation load database, and redundant margin damage and over-generation cumulative damage within a historical period can be obtained through the time load data; the over-generation power of a wind turbine selected to operate in an over-generation state can also be obtained based on the compensation power, the current power of the second target wind turbine unit, the current wind parameters, the wind parameter-load relationship parameters and the simulation load database, so that the wind turbine unit operates according to the over-generation power. Figure 2 This is a flow chart of a wind farm power control method provided by another embodiment of the present application. Figure 2 and Figure 1 The difference is that Figure 1 Step S102 in the above example can be specifically broken down into the following steps: Figure 2 Steps S1021 to S1024 in Figure 1 Step S103 in the above example can be specifically broken down into Figure 2 Steps S1031 to S1034 in .

[0051] In step S1021, based on the wind parameters and wind-parameter-load relationship parameters in the subnormal state, first time load data in the subnormal state and second time load data in the normal state are obtained from the simulation load database.

[0052] The time load data in the simulation load database corresponds to the wind parameters and the power state of the unit. The time load data corresponding to the wind parameters in the less-than-normal state and corresponding to the less-than-normal state, i.e., the first time load data, can be obtained in the simulation load database. Specifically, the time load data of the less-than-normal state corresponding to the wind parameters in the simulation load database that are relatively closer to the wind parameters in the less-than-normal state can be determined as the first time load data. Similarly, the time load data corresponding to the wind parameters in the less-than-normal state and corresponding to the normal state, i.e., the second time load data, can be obtained in the simulation load database. Specifically, the time load data of the normal state corresponding to the wind parameters in the simulation load database that are relatively closer to the wind parameters in the less-than-normal state can be determined as the second time load data. The degree of closeness between wind parameters needs to be determined using wind parameter load influence parameters. On the basis that the wind parameters are relatively closer, the wind parameter load trend relationship parameters need to be used to constrain the selection of time load data.

[0053] In some examples, based on the wind parameters under the less-normal state, the wind parameter load influence parameters and the wind parameters in the simulation load database, the similarity distance between the wind parameters under the less-normal state and the wind parameters in the simulation load database is calculated; according to the principle of close similarity distance, the time load data of the wind parameters in the less-normal state in the simulation load database that satisfy the wind parameter load trend relationship parameters with the wind parameters under the less-normal state is determined as the first time load data; according to the principle of close similarity distance, the time load data of the wind parameters in the simulation load database that satisfy the wind parameter load trend relationship parameters with the wind parameters under the normal state is determined as the second time load data.

[0054] The wind parameters under the abnormal state can be divided according to the unit time Ts, and the wind parameters within each unit time Ts form a group. The envelope data of each wind parameter within the unit time Ts can be taken as the representative wind parameter of this group of wind parameters, that is, this group of wind parameters can be represented by the representative wind parameter. The unit time Ts here is consistent with the unit time Ts corresponding to the time series load in the simulation load database.

[0055] The wind parameter load influence parameter can reflect the influence of different wind parameters on the load of the wind turbine. For example, the wind parameter load influence parameter can be realized as the influence weight of the wind parameter on the load of the wind turbine. Further, the wind parameter load influence parameter can be realized as the influence weight of the wind parameter on the load of the wind turbine components in the wind turbine. The wind parameter load influence parameter can be used to calculate the similarity distance between the wind parameters under the abnormal state and the wind parameters corresponding to the time load parameters under the abnormal state in the simulation load database. The similarity distance between two sets of wind parameters can reflect the similarity between the two sets of wind parameters. The smaller the similarity distance, the higher the similarity. For example, the similarity distance between two sets of wind parameters can be calculated according to the following formula (4):

[0056]

[0057] Among them, w r is a set of wind parameters; w i is another set of wind parameters; d(w r ,w i ) is the similarity distance between two sets of wind parameters; iw is the wind parameter load influence parameter.

[0058] In addition to considering the similarity between the wind parameters under the abnormal state and the wind parameters corresponding to the time load parameters under the abnormal state in the simulation load database, the relationship between the change of wind parameters and the change of load should also be considered. By using the wind parameter load trend relationship parameter, the load corresponding to the wind parameter corresponding to the first time load data obtained in the simulation load database needs to be able to cover the load corresponding to the wind parameter under the abnormal state, ensuring the conservatism of the first time load data, so as to avoid the safety risk caused by the load estimation being too small. The wind parameter load trend relationship parameter can reflect the relationship between the change of wind parameters and the change of load of the wind turbine components in the wind turbine group; if there is a positive correlation between the wind parameter and the wind turbine group, the load of the wind turbine components in the wind turbine group will increase with the increase of the wind parameter, and correspondingly, the time load data corresponding to the wind parameter under the abnormal state should be selected from the wind parameter corresponding to the time load parameter in the simulation load database as the first time load data; if there is a negative correlation between the wind parameter and the wind turbine group, the load of the wind turbine components in the wind turbine group will decrease with the increase of the wind parameter, and correspondingly, the time load data corresponding to the wind parameter under the abnormal state should be selected from the wind parameter corresponding to the time load parameter in the simulation load database as the first time load data. The wind parameters corresponding to the time load parameters in the simulation load database can be selected in order of similarity distance from small to large, and the first time load parameters can be obtained according to the wind parameter load trend relationship parameters. For example, the fan component includes a fixed hub, and the wind parameter includes air density. If the fixed hub is strongly correlated with the air density, and the air density is positively correlated with the load of the fixed hub, then the air density in the wind parameter corresponding to the first time load parameter found should be greater than the air density in the wind parameter under the abnormal state.

[0059] The method for determining the second time load data is similar to the method for determining the first time load data. The wind parameter load influence parameter can be used to calculate the similarity distance between the wind parameters under the subnormal state and the wind parameters corresponding to the time load parameters under the normal state in the simulation load database. In addition to considering the similarity between the wind parameters under the subnormal state and the wind parameters corresponding to the time load parameters under the normal state in the simulation load database, it is also necessary to consider the relationship between the change of wind parameters and the change of load. Using the wind parameter load trend relationship parameter, the load corresponding to the wind parameter corresponding to the second time load data obtained in the simulation load database needs to be able to cover the load corresponding to the wind parameter under the subnormal state, to ensure the conservatism of the second time load data, so as to avoid the safety risks caused by the load estimation being too small, which will not be elaborated here.

[0060] In step S1022, based on the wind parameters and wind-parameter-load relationship parameters in the over-generation state, the third time load data in the over-generation state is obtained from the simulation load database.

[0061] The time load data corresponding to the wind parameters in the over-generation state and the over-generation state, i.e., the third time load data, can be obtained in the simulation load database. Specifically, the time load data of the over-generation state corresponding to the wind parameters in the simulation load database that are relatively closer to the wind parameters in the over-generation state can be determined as the third time load data. The method of obtaining the third time load data is similar to the method of obtaining the first time load data and the second time load data. In some examples, according to the wind parameters in the over-generation state, the wind parameter load influence parameters and the wind parameters in the simulation load database, the similarity distance between the wind parameters in the over-generation state and the wind parameters in the simulation load database is calculated; according to the principle of close similarity distance, the time load data of the wind parameters in the simulation load database in the sub-normal state that meet the wind parameter load trend relationship parameters with the wind parameters in the over-generation state is determined as the third time load data. The specific contents of the calculation of similarity distance and the wind parameters in the over-generation state meeting the wind parameter load trend relationship parameters can be referred to the relevant descriptions above, which will not be repeated here.

[0062] In step S1023, the redundant margin damage and over-generation cumulative damage of the first target wind turbine generator set are obtained according to the first time load data, the second time load data and the third time load data.

[0063] The redundant margin damage of the first target wind turbine generator set can be obtained based on the first time load data and the second time load data. The over-generation cumulative damage of the first target wind turbine generator set can be obtained based on the third time load data. Specifically, the first time load data, the second time load data, and the third time load data can be converted into corresponding amplitude frequency data, and the redundant margin damage and over-generation cumulative damage can be obtained through the amplitude frequency data.

[0064] In some examples, first amplitude frequency data corresponding to the first time load data and second amplitude frequency data corresponding to the second time load data can be obtained based on the first time load data and the second time load data; redundant margin damage can be determined based on the difference between the second amplitude frequency data and the first amplitude frequency data; and third amplitude frequency data corresponding to the third time load data can be obtained based on the third time load data and determined as over-generation cumulative damage.

[0065] The amplitude frequency data corresponding to the time load data can be obtained by counting the rain flow of the time load data. The amplitude frequency data can be specifically realized as an amplitude frequency matrix, and the equivalent fatigue load can be calculated based on the amplitude frequency data. For example, the amplitude frequency matrix is The corresponding equivalent fatigue load can be obtained in, is the amplitude frequency matrix corresponding to the time load data in the shutdown state, which may include the force range of the wind turbine generator set in the shutdown state and the amplitude statistical times of each force range; L_c is the amplitude frequency matrix corresponding to the time load data under the power limit state, which may include the force range of the wind turbine under the power limit state and the amplitude statistics of each force range; P is the amplitude frequency matrix corresponding to the time load data under normal conditions, which may include the force range of the wind turbine generator set under normal conditions and the amplitude statistical times of each force range; is an amplitude frequency matrix corresponding to the time load data under the over-generation state, and the matrix may include the force range of the wind turbine generator set under the over-generation state and the amplitude statistical times of each force range; is the equivalent fatigue load corresponding to the amplitude-order matrix in the shutdown state; is the equivalent fatigue load corresponding to the amplitude-order matrix under the power-limited state; F_eq P is the equivalent fatigue load corresponding to the amplitude-order matrix under normal conditions; is the equivalent fatigue load corresponding to the amplitude frequency matrix under the over-generation state. If the force range and amplitude statistical times of the wind turbine are as shown in Table 1, the equivalent fatigue load can be calculated by the following formula (5).

[0066] Table 1

[0067] Force range <![CDATA[L1]]> <![CDATA[L2]]> … <![CDATA[L n ]]> Amplitude statistics times <![CDATA[c1]]> <![CDATA[c2]]> … <![CDATA[c n ]]>

[0068]

[0069] Among them, L i is the force range; c i For L i The corresponding amplitude statistics times; n eqis the total number of equivalent cycles, and the fatigue life corresponding to the material limit fatigue can be selected, which can be 10 7 , but not limited to this; m is the material coefficient, which can be 10, but not limited to this; F eq is the equivalent fatigue load.

[0070] The first amplitude frequency data can represent the cumulative damage caused by the wind turbine generator set operating in a subnormal state during the subnormal state time within the historical time length. The second amplitude frequency matrix can represent the cumulative damage caused by the wind turbine generator set operating in a normal state during the subnormal state time within the historical time length. The difference between the second amplitude frequency matrix and the first amplitude frequency matrix can be used as redundant margin damage. In some examples, the subnormal state may include a shutdown state and a limited power state. The shutdown state corresponds to a shutdown duration, and the limited power state corresponds to a limited power duration. The shutdown duration and the limited power duration can be divided into multiple unit times Ts, respectively, and each unit time Ts corresponds to time load data; the amplitude frequency data corresponding to the time load data of multiple unit times Ts within the shutdown duration, that is, the amplitude frequency matrix, can be accumulated and calculated to obtain the amplitude frequency matrix F corresponding to the shutdown state within the shutdown duration. p0 And the amplitude frequency matrix F corresponding to the power limit state within the power limit duration plow％ Similarly, the amplitude frequency data corresponding to the time load data of multiple unit times Ts within the power limit duration, that is, the amplitude frequency matrix, can be accumulated and calculated to obtain the amplitude frequency matrix corresponding to the normal state within the power reduction duration. And the amplitude frequency matrix corresponding to the normal state within the power limit duration The total amplitude frequency matrix can be obtained by accumulating the amplitude frequency data corresponding to the time load data of multiple unit times Ts within a period of time, that is, the amplitude frequency matrix, according to the following formula (6):

[0071]

[0072] Where F is the accumulated amplitude frequency matrix; T i is the i-th unit time; sum is the sum calculation; L1 is the force range, and other similar parameters can be deduced by analogy; is the number of amplitude statistics corresponding to the force range L1 of the i-th unit time, and other similar parameters can be deduced by analogy.

[0073] The first amplitude frequency matrix can be divided into the amplitude frequency matrix F corresponding to the shutdown state within the shutdown duration: p0 And the amplitude frequency matrix F corresponding to the power limit state within the power limit duration plow％ , the second equivalent load is divided into the amplitude frequency matrix corresponding to the normal state within the downtime And the amplitude frequency matrix corresponding to the normal state within the power limit duration Then the redundancy margin damage F no_consumed It can be obtained according to the following formula (7):

[0074]

[0075] The third amplitude frequency data can be determined as the super-accumulated damage. The method of obtaining the third amplitude frequency data according to the third time load data is similar to the method of obtaining the first amplitude frequency data according to the first time load data and the method of obtaining the second amplitude frequency data according to the second time load data, which will not be repeated here.

[0076] In the above embodiment, the amplitude frequency data can be obtained based on the time load data in the simulation load database. The equivalent fatigue load obtained based on the amplitude frequency data is very close to the actual fatigue load of the fan component, has high accuracy, and can meet the accuracy requirements. Figure 3 The deviation frequency histogram of an example of the equivalent fatigue load and the actual fatigue load of the fixed hub provided in the embodiment of the present application is shown in FIG. The comparison of the equivalent fatigue load of the fixed hub obtained by the method in the embodiment of the present application and the actual fatigue load of the fixed hub in 47 wind farms is shown in FIG. Figure 3 As shown in the figure, the horizontal axis represents the deviation between the equivalent fatigue load and the actual fatigue load, and the vertical axis represents the deviation frequency. Figure 3 As shown, the deviation between the equivalent fatigue load of the fixed hub obtained by the method in the embodiment of the present application and the actual fatigue load of the fixed hub in most wind farms is between 0 and 0.01; the deviation between the equivalent fatigue load of the fixed hub obtained by the method in the embodiment of the present application and the actual fatigue load of the fixed hub is at most 0.04, which is very small; and Figure 3 The corresponding mean absolute percentage error (MAPE) is 1.5%, which can meet the accuracy requirements for equivalent fatigue loads. It can be seen that the accuracy of the equivalent fatigue load obtained based on the amplitude frequency data obtained based on the time load data in the simulation load database in the embodiment of the present application is very high. Correspondingly, it can also be reflected that the accuracy of the amplitude frequency data obtained in the embodiment of the present application is very high, and the accuracy of the redundant margin damage, over-fire cumulative damage, over-fire predicted damage, etc. obtained based on the amplitude frequency data is also very high.

[0077] In step S1024, a second target wind turbine generator set is determined according to the redundant margin damage and the over-generation accumulated damage of the first target wind turbine generator set.

[0078] The first target wind turbine group whose redundant margin damage is greater than the over-generation accumulated damage is determined as the second target wind turbine group.

[0079] In step S1031, a third target wind turbine group whose damage difference between redundant margin damage and over-generation cumulative damage meets a predetermined condition is selected from the second target wind turbine groups.

[0080] The greater the difference between the redundant margin damage and the over-generation cumulative damage of the second target wind turbine set, the greater the damage that the second target wind turbine set can accept. The second target wind turbine set can be preferentially selected to operate in the over-generation state to quickly increase the grid-connected power of the wind farm.

[0081] In some examples, the predetermined condition may include but is not limited to the difference between the redundant margin damage and the cumulative damage of over-generation being greater than a preset difference threshold, or the first N in descending order of the difference between the redundant margin damage and the cumulative damage of over-generation, where N is a positive integer, which may be 1 or other positive integers. For example, the second target wind turbine set whose difference between the redundant margin damage and the cumulative damage of over-generation is greater than the preset difference threshold may be selected as the third target wind turbine set. For another example, the N second target wind turbine sets with the largest difference between the redundant margin damage and the cumulative damage of over-generation may be selected as the third target wind turbine set. The damage difference may essentially be an amplitude-order matrix, and the magnitude relationship of the amplitude-order matrix is ​​difficult to compare. In order to simplify the size comparison process of the damage difference between the redundant margin damage and the cumulative damage of over-generation corresponding to different wind turbine sets, the damage difference may be converted into an equivalent fatigue load, and the third target wind turbine set may be selected by comparing the size of the equivalent fatigue load. For example, the N second target wind turbine sets with the largest equivalent fatigue load obtained by the damage difference conversion may be selected as the third target wind turbine set.

[0082] In step S1032, the temporary over-generation power of the third target wind turbine generator set is obtained according to the current power and the compensation power of the third target wind turbine generator set.

[0083] The sum of the current power and the compensation power of the third target wind turbine group can be determined as the temporary over-generation power of the third target wind turbine group. The temporary over-generation power will be verified in the subsequent process. If it passes the verification, the temporary over-generation power can be determined as the over-generation power corresponding to the over-generation state; if it fails the verification, the temporary over-generation power is adjusted and verified again until the verified temporary over-generation power is obtained as the over-generation power.

[0084] In step S1033, based on the current wind parameters, temporary over-generation power, wind-parameter-load relationship parameters and the simulation load database, the expected over-generation damage of the third target wind turbine generator set is predicted.

[0085] The method of predicting the expected damage of the third target wind turbine generator set due to overgeneration based on the current wind parameters, temporary overgeneration power, wind-parameter-load relationship parameters and simulation load database is similar to the method of obtaining the cumulative damage of the wind turbine generator set due to overgeneration based on the wind parameters, wind-parameter-load relationship parameters and simulation load database when the wind turbine generator set is in an overgeneration state in the above embodiment. Temporary overgeneration power can be regarded as an overgeneration state.

[0086] In some examples, the fourth time load data under temporary over-generation power can be obtained in the simulation load database based on the current wind parameters, temporary over-generation power, and wind parameter-load relationship parameters; based on the fourth time load data, the expected over-generation damage of the third target wind turbine is predicted. The time load data corresponding to the current wind parameters and the temporary over-generation power, i.e., the fourth time load data, can be obtained in the simulation load database. Specifically, the time load data of the temporary over-generation power corresponding to the wind parameters in the simulation load database that are relatively closer to the current wind parameters can be determined as the fourth time load data. The degree of closeness between wind parameters needs to be determined using wind parameter load influence parameters. On the basis that the wind parameters are relatively closer, the selection of the fourth time load data needs to be constrained using wind parameter load trend relationship parameters and limit loads.

[0087] Specifically, the similarity distance between the current wind parameters and the wind parameters in the simulation load database can be calculated based on the current wind parameters, wind parameter load influence parameters and wind parameters in the simulation load database; according to the principle of close similarity distance, the time load data of the wind parameters in the simulation load database under temporary over-generation power that meet the wind parameter load trend relationship parameters with the current wind parameters and whose limit load is less than the predetermined safety load is determined as the fourth time load data.

[0088] The wind parameter load influence parameter can be used to calculate the similarity distance between the current wind parameter and the time load parameter in the simulation load database. The specific calculation of the similarity distance can refer to the relevant description in the above embodiment, which will not be repeated here. The time load data under the temporary over-generation power corresponding to the wind parameter in the simulation load database can be obtained in sequence according to the order of similarity distance from small to large, and it is judged whether the wind parameter of the acquired time load data and the current wind parameter meet the wind parameter load trend relationship parameter, and it is judged whether the limit load in the acquired time load data is less than the predetermined safety load. Using the wind parameter load trend relationship parameter, the load corresponding to the wind parameter corresponding to the fourth time load data obtained in the simulation load database needs to be able to cover the load corresponding to the current wind parameter, to ensure the conservatism of the fourth time load data, so as to avoid the safety risk caused by the load estimation being too small. The relationship between the wind parameter load trend relationship parameter and the selection of the fourth time load data can refer to the relevant description of the relationship between the wind parameter load trend relationship parameter and the selection of the first time load data in the above embodiment, which will not be repeated here. The limit load in the time load data is the maximum load in the time load data, and the predetermined safety load is the design safety load of the wind turbine. If the wind parameter of the acquired time load data and the current wind parameter satisfy the wind parameter load trend relationship parameter and the limit load is less than the predetermined safety load, the acquired time load data can be determined as the fourth time load data. The possibility of the limit load occurring in the over-generation state is high, and the safety and reliability of the over-generation of the wind turbine can be further improved by constraining the limit load of the fourth time load parameter.

[0089] The amplitude frequency data corresponding to the time load data, i.e., the amplitude frequency matrix, can be obtained by counting the rain flow of the fourth time load data, and the amplitude frequency matrix can be used as the over-generation predicted damage of the third target wind turbine. The method of obtaining the amplitude frequency data according to the fourth time load data can refer to the specific description of the method of obtaining the first amplitude frequency data according to the first time load data in the above embodiment, which will not be repeated here.

[0090] In step S1034, the over-generation power of the third target wind turbine is determined according to the expected damage due to over-generation and the damage difference between the third target wind turbine and the third target wind turbine, and the third target wind turbine is controlled according to the over-generation power.

[0091] The damage difference corresponding to the third target wind turbine group can represent the damage that the third target wind turbine group can still accept. According to the damage difference between the expected damage due to overgeneration and the damage corresponding to the third wind turbine group, it can be determined whether the damage sustained by the third target wind turbine group operating at the temporary overgeneration power is within the damage range that the third target wind turbine group can still accept, thereby determining how to select the overgeneration power executed by the third target wind turbine group.

[0092] In some examples, if the expected damage of over-generation is less than or equal to the damage difference, the temporary over-generation power is determined as the over-generation power; if the expected damage of over-generation is greater than the damage difference, the temporary over-generation power is reduced; based on the current wind parameters, the reduced temporary over-generation power, the wind parameter-load relationship parameters and the simulation load database, the expected damage of over-generation of the third target wind turbine is re-predicted until the expected damage of over-generation is less than or equal to the damage difference, and the reduced temporary over-generation power is determined as the over-generation power.

[0093] If the expected damage of overgeneration is less than or equal to the damage difference, it means that the damage borne by the third target wind turbine set when operating at the temporary overgeneration power is within the acceptable damage range of the third target wind turbine set, that is, the third target wind turbine set can meet the safety and reliability of the wind turbine set when operating at the temporary overgeneration power, and the temporary overgeneration power can be determined as the overgeneration power of the third target wind turbine set. If the expected damage of overgeneration is greater than the damage difference, it means that the damage borne by the third target wind turbine set when operating at the temporary overgeneration power exceeds the acceptable damage range of the third target wind turbine set, that is, the third target wind turbine set cannot meet the safety and reliability of the wind turbine set when operating at the temporary overgeneration power, and the temporary overgeneration power needs to be adjusted to reduce the damage borne by the third target wind turbine set when operating at the temporary overgeneration power, so that the damage borne by the third target wind turbine set when operating at the temporary overgeneration power is within the acceptable damage range of the third target wind turbine set. The damage borne by the third target wind turbine set when operating at the temporary overgeneration power can be reduced by reducing the temporary overgeneration power. The temporary over-generation power can be reduced by reducing the fixed power on the basis of the original temporary over-generation power each time; the power reduction coefficient can also be set and adjusted, and the temporary over-generation power after each reduction can be calculated by using the power reduction coefficient and the compensation power. For example, the temporary over-generation power can be obtained according to the following formula (8):

[0094]

[0095] Among them, P out,j is the temporary over-generation power determined for the jth time; Pout is the compensation power. When j=1, if the expected over-generation damage corresponding to the temporary over-generation power determined for the first time is greater than the damage difference, then j is increased, j=2, and correspondingly, the temporary over-generation power determined for the second time is, which is less than the temporary over-generation power determined for the first time, and so on, until the expected over-generation damage corresponding to the temporary over-generation power determined for the jth time is less than or equal to the damage difference, the temporary over-generation power determined for the jth time is determined as the over-generation power, and the third target wind turbine is controlled to operate at the over-generation power.

[0096] In some embodiments, after controlling at least part of the second target wind turbines, i.e., the third target wind turbines in the second target wind turbines, to operate in an over-generation state, the grid-connected power of the wind farm can also be updated. If the updated grid-connected power is less than the limit grid-connected power, a new compensation power is obtained based on the updated grid-connected power and the limit grid-connected power, and the second target wind turbines are re-determined. Specifically, if the updated grid-connected power is less than the limit grid-connected power, it means that there is still room for improvement in the grid-connected power of the wind farm. The above steps S102 and S103 can be repeated to re-determine the second target wind turbines that can operate in an over-generation state, and control these second target wind turbines to operate in an over-generation state. By looping the above steps, field-level control of the wind farm can be achieved, and the processing efficiency of the wind farm can be quickly improved while ensuring the safety of each wind turbine in the wind farm, and the utilization rate of wind energy of the entire wind farm can be improved.

[0097] During the power control process of the wind farm in the above embodiment, the second target wind turbine group operating in the over-generation state can also be monitored, so that when the second target wind turbine group operating in the over-generation state is about to face safety risks or cannot support the over-generation state, the second target wind turbine group can be promptly controlled to switch from the over-generation state to other unit power states.

[0098] In some examples, the redundant margin damage of the second target wind turbine group includes the redundant margin damage of the wind turbine components in the second target wind turbine group, and the over-generation cumulative damage of the second target wind turbine group includes the over-generation cumulative damage of the wind turbine components in the second target wind turbine group. The wind turbine components may include but are not limited to towers, blades, heads, fixed hubs and other components. When the second target wind turbine group is operating in an over-generation state, if the difference between the redundant margin damage and the over-generation cumulative damage of any wind turbine component in the second target wind turbine group meets the control switching condition, the second target wind turbine group is controlled to operate in a normal state or in a sub-normal state. The control switching condition includes a condition for determining that the second target wind turbine group switches from an over-generation state to a normal state. For example, the control switching condition may include that the difference between the redundant margin damage and the over-generation cumulative damage is less than a switching threshold, and the switching threshold may be set according to scenarios, requirements, experience, etc. In the case where the second target wind turbine set is operating in an over-generation state, as time goes by, the over-generation cumulative damage of the wind turbine components in the second target wind turbine set will continue to increase. If the over-generation cumulative damage of any wind turbine component is about to reach the redundant margin damage or has reached the redundant margin damage, the second target wind turbine set operating in the over-generation state is controlled to exit the over-generation state, and specifically can be switched to a normal state or to a less-than-normal state, so as to avoid the over-generation cumulative damage of the wind turbine components exceeding the redundant margin damage to have an adverse effect on the life and reliability of the wind turbine set, thereby ensuring the safety and reliability of the wind turbine set.

[0099] In some examples, the first target wind turbine group may include a wind turbine group having a wind speed higher than the rated wind speed of the group, and the first target wind turbine group includes a second target wind turbine group, and the corresponding wind speed of the second target wind turbine group is higher than the rated wind speed of the group, and the wind turbine group can support operation at rated power under the rated wind speed of the group. When the second target wind turbine group is operating in an over-generation state, if the wind speed is less than or equal to the rated wind speed of the group, the second target wind turbine group is controlled to operate in a normal state or in a less-than-normal state. When the wind speed is less than or equal to the rated wind speed of the group, the wind turbine group cannot support the over-generation state, and forcibly operating in the over-generation state will have an adverse effect on the wind turbine group. Therefore, when it is monitored that the wind speed corresponding to the second target wind turbine group operating in the over-generation state is less than or equal to the rated wind speed of the group, the second target wind turbine group can be controlled to switch to a normal state or a less-than-normal state. Specifically, if the wind speed corresponding to the second target wind turbine set is equal to the rated wind speed of the set, the second target wind turbine set can be controlled to switch to normal operation; if the wind speed corresponding to the second target wind turbine set is less than the rated wind speed of the set, the second target wind turbine set can be controlled to switch to a subnormal operation state, thereby reducing the safety risk of the second target wind turbine set and improving the safety and reliability of the second target wind turbine set.

[0100] In some embodiments, the simulation load database includes time load data simulated under different wind parameters, different unit power states, and different wind turbine component conditions. The time load data in the simulation load database and the wind parameters corresponding to the time load data can be analyzed to obtain wind parameter-load relationship parameters that can accurately characterize the relationship between wind parameters and loads such as equivalent fatigue loads. The wind parameter-load relationship parameters can be directly used in the process of determining redundant margin damage, over-generation cumulative damage, and over-generation expected damage to obtain accurate redundant margin damage, over-generation cumulative damage, and over-generation expected damage data. Figure 4 A flowchart of a wind farm power control method provided in another embodiment of the present application is shown. Figure 4 and Figure 1 The difference is that Figure 4 The wind farm power control method shown may further include steps S104 to S106.

[0101] In step S104, the equivalent fatigue load corresponding to the time load data is obtained according to the time load data in the simulation load database.

[0102] The specific content of obtaining the equivalent fatigue load according to the time load data can refer to the relevant content in the above embodiment, which will not be repeated here. The time load data may include the time load data corresponding to the fan component, and correspondingly, the equivalent fatigue load includes the equivalent fatigue load corresponding to the fan component.

[0103] In step S105, the linear relationship coefficient between the wind parameter and the equivalent fatigue load is calculated by using the corresponding wind parameters and time load data in the simulation load database, as well as the corresponding time load data and equivalent fatigue load.

[0104] The time load data in the simulation load database corresponds to the wind parameter. The equivalent fatigue load corresponding to the time load data can also be obtained through the above step S104. Through the time load data, the wind parameters and equivalent fatigue loads with corresponding relationships can be obtained. In order to facilitate analysis, the wind parameters and the equivalent fatigue loads corresponding to the wind turbine components can be normalized and calculated, and the normalized calculation algorithm is not limited here. The wind parameters and equivalent fatigue loads with corresponding relationships can be subjected to variance analysis and mutual information analysis to obtain the linear relationship parameters between the wind parameters and the equivalent fatigue loads and the influence relationship parameters between the wind parameters and the equivalent fatigue loads. The linear relationship parameters can reflect the positive or negative correlation between the wind parameters and the equivalent fatigue loads. The influence relationship parameters can reflect the correlation of the influence between the wind parameters and the equivalent fatigue loads. For example, the F-test method can be used to analyze the wind parameters and the equivalent fatigue loads to obtain the linear relationship parameters between the wind parameters and the equivalent fatigue loads, namely the F-score; the mutual information method can be used to analyze the wind parameters and the equivalent fatigue loads to obtain the influence relationship parameters between the wind parameters and the equivalent fatigue loads, namely the M-score. The wind load trend relationship parameters can be obtained based on the linear relationship parameters.

[0105] In step S106, wind parameter-load relationship parameters are obtained according to the linear relationship coefficient.

[0106] Specifically, the wind parameter load influence parameter between the wind parameter and the equivalent fatigue load can be obtained according to the linear relationship parameter and the influence relationship parameter mentioned above. For example, the wind parameter load influence parameter can be obtained according to the following formula (9):

[0107]

[0108] Among them, iw parameter-component is the wind parameter load influence parameter between the wind parameter and the equivalent fatigue load of the wind turbine components; f pic is the linear relationship parameter between wind parameter and equivalent fatigue load; m pic is the parameter of the influence relationship between wind parameter and equivalent fatigue load; max is the calculation of the maximum value.

[0109] The wind parameter load influence parameters and wind parameter load trend relationship parameters can be used to pre-cover the predicted conservatism of the equivalent fatigue load of wind turbine components in the wind turbine generator set, ensuring that the equivalent fatigue load predicted based on wind parameters is conservative, and the wind farm power control based on the redundant margin damage, over-generation cumulative damage, over-generation expected damage, etc. obtained based on the equivalent fatigue load is safe.

[0110] The second aspect of the present application also provides a power control device for a wind farm, which can be applicable to the main control system of a single wind turbine and the entire wind farm control system, and can perform power regulation for a single wind turbine or an entire wind farm. Figure 5 This is a schematic diagram of the structure of a power control device for a wind farm provided in one embodiment of the present application. Figure 5 As shown, a power control device 200 for a wind farm includes a memory 201 , a processor 202 , and a computer program stored in the memory 201 and executable on the processor 202 .

[0111] In some examples, the processor 202 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0112] The memory 201 may include a read-only memory (ROM), a random access memory (RAM), a disk storage medium device, an optical storage medium device, a flash memory device, an electrical, optical or other physical / tangible memory storage device. Therefore, generally, the memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., a memory device) encoded with software including computer executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the power control method of the wind farm according to the embodiment of the present application.

[0113] The processor 202 runs a computer program corresponding to the executable program code by reading the executable program code stored in the memory 201 , so as to implement the power control method of the wind farm in the above embodiment.

[0114] In some examples, the power control device 200 of the wind farm may further include a communication interface 203 and a bus 204. Figure 5 As shown, the memory 201, the processor 202, and the communication interface 203 are connected via a bus 204 and communicate with each other.

[0115] The communication interface 203 is mainly used to realize the communication between the modules, devices, units and / or equipment in the embodiment of the present application. The communication interface 203 can also be used to access input devices and / or output devices.

[0116] The bus 204 includes hardware, software, or both, and couples the components of the power control device 200 of the wind farm to each other. For example, but not limitation, the bus 204 may include an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), a Hyper Transport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an InfiniBand interconnect, a Low Pin Count (LPC) bus, a Memory bus, a Micro Channel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-E) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local Bus (VLB) bus, or other suitable buses or a combination of two or more of the above. Where appropriate, the bus 204 may include one or more buses. Although embodiments of the present application describe and illustrate a particular bus, the present application contemplates any suitable bus or interconnect.

[0117] The third aspect of the present application also provides a computer-readable storage medium, on which a computer program instruction is stored. When the computer program instruction is executed by a processor, the power control method of the wind farm in the above embodiment can be implemented, and the same technical effect can be achieved. To avoid repetition, it is not repeated here. Among them, the above-mentioned computer-readable storage medium may include a non-transitory computer-readable storage medium, such as a read-only memory (Read-Only Memory, referred to as ROM), a random access memory (Random Access Memory, referred to as RAM), a disk or an optical disk, etc., which is not limited here.

[0118] An embodiment of the present application also provides a computer program product. When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device can execute the power control method of the wind farm in the above embodiment and achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0119] It should be clear that each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. For device embodiments, computer-readable storage medium embodiments, and computer program product embodiments, the relevant parts can refer to the description part of the method embodiment. The present application is not limited to the specific steps and structures described above and shown in the figures. Those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application. In addition, for the sake of brevity, a detailed description of known method technologies is omitted here.

[0120] The above reference is according to the method of the embodiment of the present application, the flow chart of the device (system) and the computer program product and / or the block diagram described various aspects of the present application.It should be understood that each square box in the flow chart and / or the block diagram and the combination of each square box in the flow chart and / or the block diagram can be realized by computer program instructions.These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer or other programmable data processing device to produce a machine so that these instructions executed by the processor of the computer or other programmable data processing device enable the realization of the function / action specified in one or more square boxes of the flow chart and / or the block diagram.Such a processor can be but is not limited to a general-purpose processor, a special-purpose processor, a special application processor or a field programmable logic circuit.It can also be understood that each square box in the block diagram and / or the flow chart and the combination of the square boxes in the block diagram and / or the flow chart can also be realized by the dedicated hardware that performs the specified function or action, or can be realized by the combination of dedicated hardware and computer instructions.

[0121] Those skilled in the art should understand that the above embodiments are exemplary rather than restrictive. Different technical features appearing in different embodiments can be combined to achieve beneficial effects. Based on the study of the drawings, the specification and the claims, those skilled in the art should be able to understand and implement other variations of the disclosed embodiments. In the claims, the term "comprising" does not exclude other devices or steps; the quantifier "one" does not exclude multiple; the terms "first" and "second" are used to indicate names rather than to indicate any specific order. Any figure marks in the claims should not be understood as limiting the scope of protection. The functions of multiple parts appearing in the claims can be implemented by a single hardware or software module. The appearance of certain technical features in different dependent claims does not mean that these technical features cannot be combined to achieve beneficial effects.

Claims

1. A power control method for a wind farm, characterized in that: include: According to the grid-connected power and the limit grid-connected power of the wind farm, a compensation power for increasing the power is obtained; Based on the wind parameters of the first target wind turbine group in the wind farm in a subnormal state within a historical period, the wind parameters in an overgeneration state, the wind parameter-load relationship parameters and a preset simulation load database, a second target wind turbine group whose redundant margin damage is greater than the overgeneration cumulative damage is determined in the first target wind turbine group; Based on the compensation power, the current power of the second target wind turbine group, the current wind parameter, the wind-parameter-load relationship parameter and the simulation load database, at least part of the second target wind turbine group is controlled to operate in an over-generation state.

2. The method according to claim 1, characterized in that: The method of determining a second target wind turbine group whose redundant margin damage is greater than the accumulated damage of over-generation in the first target wind turbine group in the wind farm based on the wind parameters of the first target wind turbine group in the wind farm in the under-normal state within the historical time period, the wind parameters of the first target wind turbine group in the over-generation state, the wind parameter-load relationship parameters and the preset simulation load database, comprises: Based on the wind parameter and the wind-parameter-load relationship parameter under the subnormal state, first time load data under the subnormal state and second time load data under the normal state are obtained in the simulation load database; Based on the wind parameter in the over-generation state and the wind-parameter-load relationship parameter, obtaining the third time load data in the over-generation state in the simulation load database; Obtaining redundant margin damage and over-generation cumulative damage of the first target wind turbine generator set according to the first time load data, the second time load data and the third time load data; The second target wind turbine group is determined according to the redundant margin damage and over-generation accumulated damage of the first target wind turbine group.

3. The method according to claim 2, characterized in that The wind parameter load relationship parameters include wind parameter load influence parameters and wind parameter load trend relationship parameters; The method of obtaining the first time load data under the subnormal state and the second time load data under the normal state in the simulation load database based on the wind parameter and the wind parameter-load relationship parameter under the subnormal state includes: Calculate the similarity distance between the wind parameter in the subnormal state and the wind parameter in the simulation load database according to the wind parameter in the subnormal state, the wind parameter load influence parameter and the wind parameter in the simulation load database; According to the principle of close similarity, the time load data of the wind parameter in the less-normal state in the simulation load database that satisfies the wind parameter load trend relationship parameter with the wind parameter in the less-normal state is determined as the first time load data; According to the principle of similarity and close distance, the time load data of the wind parameter in the normal state in the simulation load database that satisfies the wind parameter load trend relationship parameter with the wind parameter in the normal state is determined as the second time load data.

4. The method according to claim 2, characterized in that: The step of obtaining the redundant margin damage and the over-generation cumulative damage of the first target wind turbine generator set according to the first time load data, the second time load data and the third time load data includes: According to the first time load data and the second time load data, first amplitude frequency data corresponding to the first time load data and second amplitude frequency data corresponding to the second time load data are obtained; Determine the redundancy margin damage according to the difference between the second amplitude frequency data and the first amplitude frequency data; According to the third time load data, third amplitude frequency data corresponding to the third time load data is obtained and determined to be super-accumulative damage.

5. The method according to claim 1, characterized in that The controlling at least part of the second target wind turbine group to operate in an over-generation state based on the compensation power, the current power of the second target wind turbine group, the current wind parameter, the wind parameter-load relationship parameter and the simulation load database comprises: Selecting a third target wind turbine group from the second target wind turbine groups, the third target wind turbine group having a damage difference between redundant margin damage and over-generation cumulative damage that meets a predetermined condition; Obtaining a temporary over-generation power of the third target wind turbine generator set according to the current power of the third target wind turbine generator set and the compensation power; Based on the current wind parameters, the temporary over-generation power, the wind-parameter-load relationship parameters and the simulation load database, predict the over-generation expected damage of the third target wind turbine generator set; According to the expected damage due to overgeneration and the damage difference of the third target wind turbine group, the overgeneration power of the third target wind turbine group is determined, and the third target wind turbine group is controlled according to the overgeneration power.

6. The method according to claim 5, characterized in that The predicting of the expected over-generation damage of the third target wind turbine generator set based on the current wind parameter, the temporary over-generation power, the wind parameter-load relationship parameter and the simulation load database includes: Based on the current wind parameter, the temporary over-generation power, and the wind-parameter-load relationship parameter, fourth time load data under the temporary over-generation power is obtained in the simulation load database; The expected over-generation damage of the third target wind turbine generator set is predicted based on the fourth time load data.

7. The method according to claim 6, characterized in that The wind parameter load relationship parameters include wind parameter load influence parameters and wind parameter load trend relationship parameters; The obtaining, based on the current wind parameter, the temporary over-generation power, and the wind-parameter-load relationship parameter, fourth time load data under the temporary over-generation power in the simulation load database includes: Calculate the similarity distance between the current wind parameter and the wind parameter in the simulation load database according to the current wind parameter, the wind parameter load influence parameter and the wind parameter in the simulation load database; According to the principle of similarity and close distance, the time load data of the wind parameters under temporary over-generation power in the simulation load database whose current wind parameters satisfy the wind parameter load trend relationship parameters and whose limit load is less than the predetermined safety load is determined as the fourth time load data.

8. The method according to claim 5, characterized in that The determining the over-generation power of the third target wind turbine generator set according to the expected over-generation damage and the damage difference of the third target wind turbine generator set comprises: If the expected damage of over-generation is less than or equal to the damage difference, the temporary over-generation power is determined as the over-generation power; If the expected damage from over-generation is greater than the damage difference, the temporary over-generation power is reduced; Based on the current wind parameters, the reduced temporary over-generation power, the wind parameter-load relationship parameters and the simulation load database, the over-generation expected damage of the third target wind turbine is re-predicted until the over-generation expected damage is less than or equal to the damage difference, and the reduced temporary over-generation power is determined as the over-generation power.

9. The method according to claim 1, characterized in that: The simulation load database includes time load data obtained by simulation under different wind parameters, different unit power states, and different wind turbine components; The method further comprises: According to the time load data in the simulation load database, an equivalent fatigue load corresponding to the time load data is obtained; Utilizing the wind parameters and time load data having a corresponding relationship in the simulation load database, as well as the time load data and equivalent fatigue load having a corresponding relationship, linear relationship parameters between the wind parameters and the equivalent fatigue load are calculated; According to the linear relationship parameters, wind parameter load relationship parameters are obtained.

10. The method according to claim 1, characterized in that After controlling at least part of the second target wind turbine generator set to operate in the over-generation state, the method further includes: Updating the grid-connected power of the wind farm; If the updated grid-connected power is less than the limit grid-connected power, a new compensation power is obtained according to the updated grid-connected power and the limit grid-connected power, and the second target wind turbine set is re-determined.

11. The method according to claim 1, characterized in that: The redundant margin damage of the second target wind turbine group includes the redundant margin damage of the wind turbine components in the second target wind turbine group, and the over-generation cumulative damage of the second target wind turbine group includes the over-generation cumulative damage of the wind turbine components in the second target wind turbine group; The method further comprises: When the second target wind turbine set is operating in an over-generation state, if the difference between the redundant margin damage of any wind turbine component in the second target wind turbine set and the over-generation cumulative damage meets the control switching condition, the second target wind turbine set is controlled to operate in a normal state or in a less-than-normal state.

12. The method according to claim 1, characterized in that The first target wind turbine generator set includes a wind turbine generator set having a wind speed higher than the rated wind speed of the wind turbine generator set; The method further comprises: When the second target wind turbine generator set operates in the overgeneration state, if the wind speed is lower than or equal to the rated wind speed of the generator set, the second target wind turbine generator set is controlled to operate in the normal state or in the less-normal state.

13. A power control device for a wind farm, characterized in that: include: a processor and a memory storing computer program instructions; When the processor executes the computer program instructions, the power control method for a wind farm as claimed in any one of claims 1 to 12 is implemented.

14. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed by a processor, the power control method for a wind farm according to any one of claims 1 to 12 is implemented.

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