A frequency modulation method for a new energy station

Abstract

The application discloses a frequency modulation method of a new energy station, and relates to the technical field of frequency control of power systems. The method comprises the following steps: monitoring a wind driven generator to obtain rotation speed monitoring data and wind monitoring data; judging the rotation speed monitoring data based on the wind monitoring data, marking wind data if the rotation speed changes, and obtaining wind marked data; analyzing the wind marked data to determine wind power conversion sensitivity under different states of the wind driven generator; monitoring the output frequency of a grid-connected point to obtain frequency monitoring data, judging the frequency monitoring data based on the rotation speed monitoring data, obtaining rotation speed marked data, analyzing the rotation speed marked data, and obtaining rotation speed conversion sensitivity; obtaining overall sensitivity of the grid-connected point based on the wind power conversion sensitivity and the rotation speed conversion sensitivity, and adjusting the wind driven generator based on the overall sensitivity. The application has the effect of improving grid-connected frequency modulation stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power system frequency control, in particular to a frequency modulation method of a new energy station. BACKGROUND

[0002] With the deep adjustment of global energy structure and the accelerated promotion of the "double carbon" target, new energy power generation technologies represented by wind power and photovoltaic power generation are widely used due to their clean and low-carbon characteristics, and their penetration rate in the power system continues to rise. However, the output of wind power plants has significant intermittency and volatility, which makes the wind power plant grid-connected subject to natural conditions such as wind speed, resulting in unstable system frequency.

[0003] In the prior art, energy storage devices are arranged in wind power plants to compensate for the lack of output frequency, thereby ensuring the stability of the output frequency. However, since the power output of the wind power plant is obtained by rectification through a converter, the rectification mechanism of the converter is fixed, so when the external environment changes, the output result of the converter is first detected, and then the energy storage device is controlled according to the output result change, so that the frequency modulation process is not timely, resulting in fluctuations in the output frequency, which needs to be improved. SUMMARY

[0004] In order to improve the grid-connected frequency modulation stability, the present application provides a frequency modulation method of a new energy station.

[0005] The present application provides a frequency modulation method of a new energy station, which adopts the following technical scheme:

[0006] A frequency modulation method of a new energy station, comprising:

[0007] Obtain the grid-connected frequency requirement of the grid-connected point and the power generation power of the wind power generator, and group the wind power generators in the wind power plant according to the grid-connected frequency requirement and the power generation power to determine the wind power generators required to be connected to each grid-connected point;

[0008] Based on the grid-connected frequency requirement, the wind power generators connected to the grid-connected point are controlled to determine the initial state of each wind power generator on the grid-connected point, and the speed reference data and the wind reference data are obtained;

[0009] The speed of the wind power generator is monitored to obtain speed monitoring data, and the environmental information of the wind power generator is monitored to obtain wind monitoring data;

[0010] The wind monitoring data is subjected to wind power data change monitoring to obtain a change time point, and the rotational speed monitoring data is judged based on the change time point to determine whether the rotational speed of the wind turbine at the corresponding time point changes. If the rotational speed changes, the wind data is marked to obtain wind marked data;

[0011] The wind marked data is analyzed to determine the wind power conversion sensitivity under different wind turbine states;

[0012] The output frequency of the grid-connected point is monitored to obtain frequency monitoring data. Based on the rotational speed monitoring data, the time point when the rotational speed changes is determined to obtain a rotational speed time point. The frequency monitoring data is judged based on the rotational speed time point to determine whether the output frequency of the grid-connected point at the corresponding time point changes;

[0013] If the output frequency changes, the rotational speed data is marked to obtain rotational speed marked data. The rotational speed marked data is analyzed to determine the sensitivity of the output frequency under different rotational speeds to obtain rotational speed conversion sensitivity;

[0014] Based on the wind power conversion sensitivity and the rotational speed conversion sensitivity, the overall sensitivity of the grid-connected point is obtained. Based on the overall sensitivity, the overall fluctuation range of the wind turbine is determined, and the wind turbine is adjusted based on the overall fluctuation range.

[0015] Preferably, the rotational speed monitoring data is subjected to difference calculation with the rotational speed reference data to obtain a rotational speed fluctuation value. The rotational speed fluctuation value is counted based on the time data to obtain a rotational speed fluctuation curve;

[0016] Obtain the yaw data of the wind turbine, and based on the yaw data and the wind direction data in the wind monitoring data, determine the deviation data between the wind turbine and the wind direction;

[0017] Obtain the fan working data of the wind turbine, and based on the fan working data, the deviation data and the wind speed data in the wind monitoring data, determine the force of the wind on the fan under different wind monitoring data to obtain wind power data;

[0018] The wind power data is subjected to difference calculation with the wind power reference data to obtain a wind power fluctuation value. Based on the built-in first comparison threshold, the wind power fluctuation value is screened to obtain the wind power fluctuation value that exceeds the first comparison threshold. The time point corresponding to the wind power fluctuation value is read to obtain a wind power change time point;

[0019] Based on the wind power change time point, the rotational speed fluctuation value of the rotational speed fluctuation curve is read to obtain to-be-judged rotational speed fluctuation data. The to-be-judged rotational speed fluctuation data is compared with the built-in second comparison threshold. The wind power change time point corresponding to the to-be-judged rotational speed fluctuation data greater than the second comparison threshold is marked to obtain a marked time point;

[0020] The wind fluctuation value is marked based on the marking time point to obtain wind marking data.

[0021] Preferably, S51, based on the marking time point, the data change amount of the rotation speed monitoring data corresponding to the time point is judged to determine the rotation speed change amount;

[0022] S52, based on the fan working data of the variable time point, the wind marking data is divided to determine the wind marking data under the same fan working data, and is recorded as a state marking group;

[0023] S53, the wind force rotation speed change curve between the wind marking data in the state marking group and the rotation speed change amount is drawn;

[0024] S54, based on artificial intelligence, the wind force rotation speed change curve is judged to determine the variable relationship between wind force and rotation speed under different fan working states, and the wind force conversion sensitivity under different fan working states is determined based on the variable relationship.

[0025] Preferably, based on the wind force rotation speed change curve, the variable relationship between wind force and rotation speed under different fan working states is obtained and recorded as a wind force variable relationship;

[0026] Based on the wind force variable relationship, the rotation speed monitoring data is calculated to determine the variable amount of wind force when the rotation speed changes by one standard rotation speed unit, and the minimum wind force variable amount is obtained;

[0027] Based on the minimum wind force variable amount, the wind force data is matched to determine whether there is a variable amount of minimum wind force variable amount in the wind force data, if it is determined that there is, the rotation speed monitoring data is matched according to the time point corresponding to the minimum wind force variable amount to determine whether the rotation speed monitoring data changes;

[0028] If it is determined that the change occurs, the standard unit is taken as the minimum variable unit of rotation speed change, and based on the minimum variable unit of rotation speed and the wind force variable relationship, the corresponding wind force conversion sensitivity is constructed;

[0029] If it is determined that the rotation speed monitoring data does not change, the variable amount of wind force when the rotation speed changes by two standard rotation speed units is determined according to the wind force variable relationship, until the time point corresponding to the corresponding wind force variable amount matches the rotation speed monitoring data successfully.

[0030] Preferably, based on the built-in frequency fluctuation threshold, the frequency monitoring data is filtered to obtain the time point at which the output frequency fluctuation is greater than the frequency fluctuation threshold, and the time point is marked as a frequency fluctuation time point;

[0031] Based on the frequency fluctuation time point, the rotation speed monitoring data is read to obtain the to-be-judged rotation speed data;

[0032] The rotational speed data to be judged is subtracted from the rotational speed reference data to determine a rotational speed variation; the frequency monitoring data at the frequency fluctuation time point is subtracted from the frequency fluctuation threshold to obtain a frequency variation;

[0033] The rotational speed variation and the frequency variation are correspondingly grouped to obtain rotational speed frequency group data;

[0034] The multiple rotational speed frequency group data are subjected to mathematical statistics to determine a rotational speed variation relationship, and the rotational speed monitoring data and the frequency monitoring data are verified based on the rotational speed variation relationship and the built-in standard frequency unit to determine a minimum variation between the rotational speed and the frequency, and the rotational speed conversion sensitivity between the rotational speed and the frequency is determined based on the minimum variation.

[0035] Preferably, S81, based on the minimum variation of the rotational speed in the wind conversion sensitivity and the minimum variation of the frequency in the rotational speed conversion sensitivity, the wind conversion sensitivity and the rotational speed conversion sensitivity are coupled to obtain an overall sensitivity between the wind and the frequency;

[0036] S82, according to the minimum variation of the frequency in the overall sensitivity, the fluctuation range of the wind acting on the wind driven generator is determined to obtain an overall fluctuation range;

[0037] S83, the wind monitoring data at the current time point is recorded as current wind data, and the blade working data at the current time point is recorded as real-time state data, the current wind data is judged based on the real-time state data to determine the current wind force acting on the wind driven generator;

[0038] S84, the frequency monitoring data is judged to determine the frequency variation trend, and the working state of the wind driven generator is judged based on the frequency variation trend, the current wind force and the overall fluctuation range to obtain adjustment data;

[0039] S85, the working state of the wind driven generator is adjusted to the data edge of the overall fluctuation range based on the adjustment data.

[0040] Preferably, S841, if the frequency variation trend is a downward trend, the first adjustment difference data is obtained by subtracting the current wind force from the upper limit of the overall fluctuation range;

[0041] S842, the maximum conversion coefficient of the blade is obtained, and the maximum wind force that can be reached is determined based on the current wind data and the maximum conversion coefficient;

[0042] S843, compare the maximum wind action force with the first to be adjusted difference value data, determine whether the maximum wind action force meets the requirements of the first to be adjusted difference value data, if it is determined that the requirements of the first to be adjusted difference value data are met, the first adjustment data of the wind turbine blade under the current wind data is determined according to the first to be adjusted difference value data;

[0043] S844, if it is determined that the requirements of the first to be adjusted difference value data are not met, the braking coefficient of the braking system is obtained, and the braking coefficient of the braking system is adjusted according to the difference between the first to be adjusted difference value data and the maximum wind action force, to obtain the second adjustment data;

[0044] S845, if the frequency change trend is an upward trend, the second to be adjusted difference value data is obtained by differentially calculating the current wind action force according to the lower limit of the overall fluctuation range, and the wind turbine is adjusted according to the second to be adjusted difference value data to obtain the third adjustment data of the wind turbine.

[0045] In summary, the present application includes at least one of the following beneficial technical effects:

[0046] By utilizing the grid-connected frequency requirement of the grid-connected point and the power generation power of the wind turbine, the number of wind turbines required to be connected under the corresponding grid-connected frequency requirement is determined, so that a large number of wind turbines in the wind power station are processed separately, improving the accuracy of monitoring and adjustment. By utilizing the adjustment result when connected to the grid, the initial state of the wind power station when connected to the grid is determined, thereby determining the reference value. The rotational speed monitoring data and wind monitoring data during the operation of the wind turbine are evaluated with the reference value as the reference to determine the sensitivity of the rotational speed of the wind turbine to the wind force and the sensitivity of the output frequency change to the rotational speed. Furthermore, the wind turbine can be adjusted in advance according to the rotational speed conversion sensitivity and the wind force conversion sensitivity, so that the wind turbine can quickly respond when the output frequency changes to maintain the stability of the output frequency.

[0047] With the help of the built-in standard rotational speed unit, the wind force variation relationship is calculated to determine whether there is a corresponding minimum wind force variation in the wind force data, and to determine whether there is corresponding data variation in the rotational speed monitoring data when the minimum wind force variation occurs, thereby determining the minimum variation between wind force and rotational speed. The wind force conversion sensitivity constructed is more convincing and more consistent with the actual situation, improving the accuracy of the frequency modulation result when frequency modulation, and ensuring the stability of the output frequency.

[0048] By judging the working state of the fan blade, it is determined whether the adjustment amount required by the frequency change trend can be met by adjusting only the conversion coefficient between the fan blade and the wind. When it is determined that the maximum wind force that can be converted by the wind power generator can meet the first to-be-adjusted difference value data, the first to-be-adjusted difference value data is directly taken as the final adjustment target of the wind power generator fan blade to adjust the wind power generator fan blade, so that the adjustment process maximally reduces the variation of the wind power generator operation, and then the adjusted wind power generator is still within the wind power conversion sensitivity and speed conversion sensitivity range, thereby improving the adjustment accuracy. When the maximum wind force cannot meet the first to-be-adjusted difference value data, the brake system is adjusted to gradually release the restriction of the brake system on the speed of the wind power generator, so that the speed of the wind power generator can reach the speed corresponding to the upper limit of the overall fluctuation range, and then the entire adjustment process has stability, thereby maintaining the stability of the output frequency. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 The step flowchart of the frequency regulation method of the new energy station of the embodiment. DETAILED DESCRIPTION

[0050] The following will be described in detail with reference to the accompanying Figure 1 The application will be further described in detail.

[0051] The embodiment of the application discloses a frequency regulation method of a new energy station.

[0052] Embodiment: as shown in the figure, the frequency regulation method of the new energy station of the application comprises: Figure 1

[0053] S1, acquiring the grid-connected frequency demand of a grid-connected point and the power generation power of a wind power generator, and grouping the wind power generators in the wind power station according to the grid-connected frequency demand and the power generation power to determine the wind power generators required to be connected to each grid-connected point;

[0054] S2, based on the grid-connected frequency demand, regulating and controlling the wind power generators connected to the grid-connected point to determine the initial state of each wind power generator on the grid-connected point, and obtaining speed reference data and wind reference data; wherein the speed data is the speed required to match the power grid when connected to the grid, that is, when the speed reaches the speed data, it indicates that the output frequency reaches the grid-connected demand.

[0055] S3, monitoring the speed of the wind power generator to obtain speed monitoring data, and monitoring the environmental information of the wind power generator to obtain wind monitoring data;

[0056] ​S4, wind monitoring data is monitored for wind data changes, a change time point is obtained, and the change time point is used to judge the rotational speed monitoring data to determine whether the rotational speed of the wind turbine at the corresponding time point changes, if the rotational speed changes, the wind data is marked to obtain wind marked data;

[0057] S5, the wind marked data is analyzed to determine the wind power conversion sensitivity under different wind turbine states; the sensitivity value refers to the influence of the change value of the wind speed or the change value of the wind direction on the rotational speed when the positive direction is adjusted. For example, if the rotational speed increases or decreases by one unit, the change value of the wind power increases or decreases by n units.

[0058] S6, the output frequency of the grid-connected point is monitored to obtain frequency monitoring data, the time point when the rotational speed changes is determined based on the rotational speed monitoring data to obtain the rotational speed time point, and the frequency monitoring data is judged based on the rotational speed time point to determine whether the output frequency of the grid-connected point at the corresponding time point changes;

[0059] S7, if the output frequency changes, the rotational speed data is marked to obtain rotational speed marked data, the rotational speed marked data is analyzed to determine the sensitivity of the output frequency under different rotational speeds, and the rotational speed conversion sensitivity is obtained;

[0060] S8, based on the wind power conversion sensitivity and the rotational speed conversion sensitivity, the overall sensitivity of the grid-connected point is obtained, and the overall fluctuation range of the wind turbine is determined based on the overall sensitivity, and the wind turbine is adjusted based on the overall fluctuation range.

[0061] In this embodiment, by using the grid-connected frequency demand of the grid-connected point and the power generation power of the wind turbine, the number of wind turbines required to be connected is determined under the corresponding grid-connected frequency demand, so that a large number of wind turbines in the wind power station are processed separately, the accuracy of monitoring and adjustment is improved, and the initial state of the wind power station when connected to the grid is determined by using the adjustment result when connected to the grid, so as to determine the reference value. The rotational speed monitoring data and the wind monitoring data in the operation of the wind turbine are evaluated based on the reference value to determine the sensitivity of the rotational speed of the wind turbine to the wind power and the sensitivity of the change of the output frequency to the rotational speed, and then the wind turbine can be adjusted in advance according to the rotational speed conversion sensitivity and the wind power conversion sensitivity, so that the wind turbine can quickly respond when the output frequency changes to maintain the stability of the output frequency.

[0062] For example, the final adjustment target is determined by determining the output frequency that the wind power plant needs to maintain when connecting to the power grid. Assuming that the grid connection frequency requirement is 50 Hz, the system frequency will rise when the active power supply in the wind power plant system is greater than the load demand, and vice versa, if the load demand is greater than the active power, the system frequency will decrease. Therefore, when the grid connection frequency requirement and the load of the power grid are certain, the active power output required by the wind power plant can be effectively determined, and the number of wind turbines required to be connected to each grid connection point can be determined according to the power generation of each wind turbine. Assuming that there are four wind turbines a, b, c, and d, and the output power of each is 1, and the required power of the grid connection point is 2, then a and b can be connected to one grid connection point, and c and d can be connected to another grid connection point. Therefore, in order to ensure the stability of the grid connection, only a and b need to be monitored, and c and d need to be monitored, reducing the data variables of each grid connection point, making the analysis more convenient, and improving the analysis efficiency and accuracy. At the same time, the power generation of the wind turbine is matched and grouped, which makes full use of wind energy, improves the utilization rate of wind energy, and reduces the waste of natural resources.

[0063] After determining the wind turbines required to be connected to each grid connection point, in order to ensure the stability of the grid connection, the wind turbines in the wind power plant are adjusted manually to obtain the initial working state of each wind turbine in the wind power plant, that is, when the wind turbine reaches the corresponding reference data, the grid connection has stability, and the complex power data is quantified into the running state of the wind turbine.

[0064] After determining the state of the wind turbine at each grid connection point, the speed of the wind turbine and the environmental information are monitored to determine whether the speed of the wind turbine changes and whether the external environment (wind speed, wind direction) changes. Since the output power of the wind turbine is determined by the speed, and the speed of the wind turbine is determined by the force of the wind acting on the fan blade, monitoring the speed and external environment can effectively determine the change state of the wind turbine.

[0065] The change in the force of the wind acting on the fan blades is monitored by monitoring the wind monitoring data, and the rotational speed is monitored by combining the rotational speed monitoring data, so as to determine how much the change in the force of the wind acting on the fan blades will cause the change in the rotational speed, for example, the rotational speed will increase by 1 when the force of the wind acting on the fan blades increases by 10, so as to determine the conversion relationship between the wind power and the rotational speed. However, there is a dullness between the wind power and the rotational speed of the wind turbine, that is, there is a certain data sensitivity, rather than real-time accurate conversion, for example, the relationship between the wind power and the rotational speed is that the rotational speed will increase by 1 when the force of the wind acting on the fan blades increases by 10, and this data conversion relationship does not mean that the rotational speed will increase by 0.1 when the force of the wind acting on the fan blades increases by 1. Therefore, the sensitivity of the wind power conversion into the rotational speed needs to be determined, so that the wind turbine can be adjusted in time when the external environment changes, so as to ensure the stability of the output power, and further ensure the stability of the output frequency.

[0066] Similarly, the sensitivity between the rotational speed and the output frequency is determined, and the relationship between the two is determined. Further, the influence of the external environment (wind speed, wind direction) on the output frequency when the external environment changes can be determined, so that the wind turbine can be adjusted in time by using the redundancy space between each other when the external environment changes, so as to ensure that the state of the wind turbine always remains the initial state, and the stability of the grid connection is improved.

[0067] In step S4, the wind monitoring data is monitored to obtain the change time point, and the rotational speed monitoring data is judged based on the change time point to determine whether the rotational speed of the wind turbine at the corresponding time point changes. If the rotational speed changes, the wind data is marked to obtain wind marked data, including the following steps:

[0068] S41, the rotational speed monitoring data is difference calculated with the rotational speed reference data to obtain the rotational speed fluctuation value, and the rotational speed fluctuation value is counted based on the time data to obtain the rotational speed fluctuation curve; wherein the rotational speed reference data is the rotational speed generated when the output frequency reaches the demand.

[0069] S42, the yaw data of the wind turbine is obtained, and the deviation data between the wind turbine and the wind direction is determined based on the yaw data and the wind direction data in the wind monitoring data; wherein the deviation data is the direction angle when the wind changes the wind direction and the wind turbine does not adjust correspondingly.

[0070] S43, the fan blade working data of the wind turbine is obtained, and the force of the wind on the fan blades under different wind monitoring data is determined based on the fan blade working data, the deviation data and the wind speed data in the wind monitoring data to obtain the wind data; wherein the wind data refers to the force of the wind on the wind turbine at each moment.

[0071] S44, the wind data is differentially calculated with the wind reference data to obtain a wind fluctuation value, and based on the built-in first comparison threshold, the wind fluctuation value exceeding the first comparison threshold is screened to obtain the wind fluctuation value, and the time point corresponding to the wind fluctuation value is read to obtain the wind change time point; wherein the speed reference value and the wind reference data are the same, both refer to the required acting wind power when the output power meets the demand.

[0072] S45, based on the wind change time point, the speed fluctuation curve is read to obtain the to-be-judged speed fluctuation data, and the to-be-judged speed fluctuation data is compared with the built-in second comparison threshold, and the wind change time point corresponding to the to-be-judged speed fluctuation data greater than the second comparison threshold is marked to obtain the marked time point; wherein the marked time point refers to the time point when the speed changes when the wind changes.

[0073] S46, based on the marked time point, the wind fluctuation value is marked to obtain the wind marked data. Wherein the wind marked data refers to the wind monitoring data that can cause the speed change.

[0074] In this embodiment, based on the relationship between the wind turbine fan blade and the wind monitoring data, the monitored wind monitoring data is converted into wind data acting on the fan blade, and then the variable wind monitoring data is normalized into unified wind data, which simplifies the data judgment complexity. The wind fluctuation is judged by the wind data, the wind fluctuation time point is determined, and the speed fluctuation curve is read and judged by the wind fluctuation time point, so as to determine whether the speed changes when the wind changes. Through screening of a large amount of wind monitoring data and speed monitoring data, the accuracy of the to-be-judged data is ensured, and the accuracy of the sensitivity judgment is improved.

[0075] For example, the output frequency of the access power grid is fixed, and the fixed output frequency corresponds to the fixed output power, and the fixed output power corresponds to the fixed speed, so that the speed in the initial state is taken as the reference value of the wind turbine, the speed of the wind turbine is judged, and it is determined whether the speed of the wind turbine changes. The speed monitoring data is differentially calculated with the speed reference data, and the calculated difference is counted to obtain the speed fluctuation curve.

[0076] At the same time, the wind speed data and the wind direction data in the wind monitoring data and the fan working data of the wind turbine are used to judge the wind acting force, so as to determine the acting force of the fan under the current wind monitoring data. Since the wind resource is a natural resource which is not controllable and stable and sustainable by human beings, there is a certain slight fluctuation, so the first comparison threshold is used as the judgment standard of the wind change to judge the wind and determine whether the wind acting on the wind turbine changes.

[0077] When it is determined that the wind force received by the wind turbine exceeds the normal fluctuation range, the corresponding change in the rotation speed is determined by reading the rotation speed at the corresponding time point. For example, when the wind force is 10, the wind force that can be determined due to the characteristics of the wind under normal circumstances is ±0.5 fluctuation, and when the wind force received exceeds ±0.5 fluctuation, it is first determined that the wind force has changed. At this time, the change in the wind force can be caused by the change in the wind speed or the change in the wind direction. By reading the rotation speed at the time point when the change in the wind force is determined, it is assumed that at 00:30, it is determined that the wind force has changed, the rotation speed at 00:30 is read, and it is determined whether the rotation speed at this time has changed. If the rotation speed also changes, it indicates that the change in the wind force at the marker time point causes the change in the rotation speed of the wind turbine, and therefore the wind force change and the rotation speed change need to be analyzed uniformly to determine the conversion relationship between them.

[0078] In step S5, the wind marker data is analyzed to determine the wind force conversion sensitivity under different wind turbine states, including the following steps:

[0079] S51, based on the marker time point, the data change amount of the rotation speed monitoring data at the corresponding time point is determined to determine the rotation speed change amount;

[0080] S52, based on the fan working data at the change time point, the wind marker data is divided to determine the wind marker data under the same fan working data, and is recorded as a state marker group;

[0081] S53, the wind force rotation speed change curve between the wind marker data in the state marker group and the rotation speed change amount is drawn;

[0082] S54, based on artificial intelligence, the wind force rotation speed change curve is determined to determine the change relationship between the wind force and the rotation speed under different fan working states, and the wind force conversion sensitivity under different fan working states is determined based on the change relationship.

[0083] For example, after determining which wind monitoring data can cause the rotation speed of the wind turbine to change, the data change relationship between the change amount of the wind monitoring data and the change amount of the rotation speed of the wind turbine is constructed, so that the sensitivity of the wind turbine to the wind force change can be determined. However, since different fan working states exhibit different wind forces on the same wind monitoring data, the marked wind marker data needs to be divided according to the fan working data to ensure the accuracy of the data to be analyzed, thereby improving the sensitivity of the rotation speed of the wind turbine to the wind speed.

[0084] In step S54, the wind speed change curve is judged based on artificial intelligence to determine the change relationship between wind speed and rotation speed under different fan blade working states, and the wind speed conversion sensitivity under different fan blade working states is determined based on the change relationship, including the following steps:

[0085] S541, based on the wind speed change curve, the change relationship between wind speed and rotation speed under different fan blade working states is obtained and recorded as wind speed change relationship;

[0086] S542, based on the wind speed change relationship, the rotation speed monitoring data is calculated to determine the change amount of wind speed when the rotation speed changes by one standard rotation speed unit, and the minimum wind speed change amount is obtained;

[0087] S543, based on the minimum wind speed change amount, the wind speed data is matched to determine whether there is a case where the change amount is the minimum wind speed change amount in the wind speed data, if it is determined that there is, the rotation speed monitoring data is matched according to the time point corresponding to the minimum wind speed change amount to determine whether the rotation speed monitoring data changes;

[0088] S544, if it is determined that the change occurs, the standard unit is taken as the minimum change unit of rotation speed change, and the corresponding wind speed conversion sensitivity is constructed based on the minimum change unit of rotation speed and the wind speed change relationship;

[0089] S545, if it is determined that the rotation speed monitoring data does not change, the change amount of wind speed when the rotation speed changes by two standard rotation speed units is determined according to the wind speed change relationship, until the time point corresponding to the corresponding wind speed change amount is matched successfully with the rotation speed monitoring data.

[0090] In this embodiment, by using the built-in standard rotation speed unit to calculate the wind speed change relationship, it is determined whether there is a corresponding minimum wind speed change amount in the wind speed data, and whether the rotation speed monitoring data changes corresponding to the appearance of the minimum wind speed change amount, so as to determine the minimum change amount between wind speed and rotation speed, so that the wind speed conversion sensitivity constructed is more convincing and more consistent with the actual situation, the accuracy of the frequency modulation result is improved when frequency modulation, and the stability of the output frequency is ensured.

[0091] For example, when the wind force acting on the fan blade increases by 20, the rotation speed of the wind turbine changes, and the rotation speed increases by 2. At this time, the data relationship between the two is 10:1, that is, the rotation speed increases by 1 for every 10 increase in the wind force. However, in the actual process, due to the existence of inertia, when the wind force increases by 10, the rotation speed does not increase by 1. Therefore, the inertia (i.e., the minimum change amount) between the wind force and the rotation speed needs to be determined according to the wind monitoring data and the rotation speed monitoring data, and then the sensitivity of the wind turbine rotation speed to the wind force is determined. For example, the sensitivity is 20:2, that is, the rotation speed increases by 2 for every 20 increase in the wind force, and the rotation speed does not change in the interval from 0 to 20 increase in the wind force. The determined sensitivity is more consistent with the actual situation, and the accuracy of the determination is improved.

[0092] In step S7, if the output frequency changes, the rotation speed data is marked to obtain rotation speed marked data, and the rotation speed marked data is analyzed to determine the sensitivity of the output frequency at different rotation speeds, and the rotation speed conversion sensitivity is obtained, including the following steps:

[0093] S71, based on the built-in frequency fluctuation threshold, the frequency monitoring data is filtered to obtain the time point at which the output frequency fluctuation is greater than the frequency fluctuation threshold, and the time point is marked as a frequency fluctuation time point;

[0094] S72, based on the frequency fluctuation time point, the rotation speed monitoring data is read to obtain the rotation speed data to be determined;

[0095] S73, the difference between the rotation speed data to be determined and the rotation speed reference data is calculated to determine the rotation speed change amount; the difference between the frequency monitoring data at the frequency fluctuation time point and the frequency fluctuation threshold is calculated to obtain the frequency change amount;

[0096] S74, the rotation speed change amount and the frequency change amount are correspondingly grouped to obtain rotation speed frequency group data;

[0097] S75, the rotation speed frequency group data is subjected to mathematical statistics to determine the rotation speed change relationship, and the rotation speed monitoring data and the frequency monitoring data are verified based on the rotation speed change relationship and the built-in standard frequency unit to determine the minimum change amount between the rotation speed and the frequency, and the rotation speed conversion sensitivity between the rotation speed and the frequency is determined based on the minimum change amount.

[0098] For example, when judging the sensitivity between frequency and rotating speed, the output frequency is fixed when grid-connected, so the frequency fluctuation is screened to determine the rotating speed change value when the frequency changes, and then the data relationship between the frequency change and the rotating speed change is constructed, and the data relationship between the two is determined. Similarly, the minimum change between the two needs to be judged to further determine the sensitivity of the frequency change to the rotating speed change, and then the sensitivity between wind power and rotating speed and the sensitivity between rotating speed and frequency are used to provide fluctuation redundancy space for the adjustment of the wind power generator when the external environment (wind speed, wind direction) changes. The system can adjust the relevant working data of the wind power generator before the fluctuation redundancy space collapses to ensure the stability of the output frequency and improve the stability of the grid-connected access.

[0099] In step S8, the overall sensitivity of the grid-connected point is obtained based on the wind power conversion sensitivity and the rotating speed conversion sensitivity, the overall fluctuation range of the wind power generator is determined based on the overall sensitivity, and the wind power generator is adjusted based on the overall fluctuation range, including the following steps:

[0100] S81, based on the minimum change of the rotating speed in the wind power conversion sensitivity and the minimum change of the frequency in the rotating speed conversion sensitivity, the wind power conversion sensitivity and the rotating speed conversion sensitivity are coupled to obtain the overall sensitivity between wind power and frequency;

[0101] S82, according to the minimum change of the frequency in the overall sensitivity, the fluctuation range of the wind acting on the wind power generator is determined to obtain the overall fluctuation range;

[0102] S83, the wind monitoring data at the current time point is recorded as the current wind data, and the fan working data at the current time point is recorded as the real-time state data, the current wind data is judged based on the real-time state data to determine the current wind force acting on the wind power generator;

[0103] S84, the frequency monitoring data is judged to determine the frequency change trend, the working state of the wind power generator is judged based on the frequency change trend, the current wind force and the overall fluctuation range to obtain the adjustment data;

[0104] S85, the working state of the wind power generator is adjusted to the data edge of the overall fluctuation range based on the adjustment data.

[0105] Exemplary, after determining the sensitivity of the rotation speed to the wind force and the sensitivity of the frequency to the rotation speed, the sensitivity of the frequency to the wind force is determined by coupling the two, that is, when the wind force reaches how much, the frequency will change, and the amount of change of the frequency is determined by real-time monitoring of the frequency monitoring data to determine the change trend of the frequency. If the load in the power grid increases, the required power needs to increase, and under the condition that the output power does not increase, the corresponding output frequency will decrease, thereby causing the grid connection to be unstable. In order to ensure the stability of the grid connection, the output frequency needs to be pulled up, and the pull-up of the output frequency corresponds to the increase of the output power. Therefore, the wind force acting on the wind generator needs to be adjusted to achieve the effect of improving the output power and pulling up the output frequency. Since the output frequency is still in a safe state, the output frequency cannot be adjusted in advance. In order to ensure that the output frequency can be adjusted in time when the output frequency decreases or increases to ensure the stability of the output frequency, the working state of the wind generator in the current wind power plant needs to be at the data edge of the overall fluctuation range, so that the wind generator can be adjusted most quickly to maintain the stability of the output frequency when the output frequency changes.

[0106] In step S84, the frequency monitoring data is judged to determine the frequency change trend, and the working state of the wind generator is judged based on the frequency change trend, the current wind force and the overall fluctuation range to obtain adjustment data, including the following steps:

[0107] S841, if the frequency change trend is a downward trend, then the current wind force is calculated by difference according to the upper limit of the overall fluctuation range to obtain first adjustment difference data;

[0108] S842, the maximum conversion coefficient of the fan blade is obtained, and the maximum wind force that can be achieved based on the current wind data and the maximum conversion coefficient is determined;

[0109] S843, the maximum wind force is compared with the first adjustment difference data to determine whether the maximum wind force meets the requirements of the first adjustment difference data. If it is determined that the requirements of the first adjustment difference data are met, then the first adjustment data of the fan blade of the wind generator under the current wind data is determined according to the first adjustment difference data;

[0110] S844, if it is determined that the requirements of the first adjustment difference data are not met, then the braking coefficient of the braking system is obtained, and the braking coefficient of the braking system is adjusted according to the difference between the first adjustment difference data and the maximum wind force to obtain second adjustment data; wherein the second adjustment data includes adjustment data of the fan blade and adjustment data of the braking system.

[0111] S845, if the frequency change trend is an upward trend, then the current wind force is differentially calculated according to the lower limit of the overall fluctuation range to obtain second to-be-adjusted difference data, and the wind turbine is adjusted according to the second to-be-adjusted difference data to obtain third adjustment data of the wind turbine.

[0112] In the embodiment, when adjusting the working state of the wind turbine, the working state of the fan blade is determined to determine whether the adjustment amount required by the frequency change trend can be met by adjusting only the conversion coefficient between the fan blade and the wind. When it is determined that the maximum wind force that can be converted by the wind turbine can meet the first to-be-adjusted difference data, the first to-be-adjusted difference data is directly used as the final adjustment target of the fan blade of the wind turbine to adjust the fan blade of the wind turbine, so that the adjustment process reduces the variation of the wind turbine to the greatest extent, and the adjusted wind turbine is still within the wind conversion sensitivity and rotational speed conversion sensitivity range, thereby improving the adjustment accuracy. When the maximum wind force cannot meet the first to-be-adjusted difference data, the brake system is adjusted to gradually release the restriction of the brake system on the rotational speed of the wind turbine, so that the rotational speed of the wind turbine reaches the rotational speed corresponding to the upper limit of the overall fluctuation range, thereby making the entire adjustment process stable, and thereby maintaining the stability of the output frequency.

[0113] For example, due to the fluctuation of the load in the power grid, the demand for output power is also fluctuant, which leads to instability of the output frequency. In order to ensure the stability of the output frequency, the working state of the wind turbine needs to be adjusted according to the change trend of the output frequency, so that the wind turbine is at the edge position affecting the variation of the output frequency, so that the wind power station can respond in time when the fluctuation of the output frequency exceeds the normal fluctuation, and the output frequency is stabilized in time to ensure the stability of the output frequency.

[0114] During the adjustment process, the fan blade angle of the wind turbine is adjusted first, that is, the force of the wind on the fan blade is increased or decreased, and the rotational speed sensitivity to the wind is ensured to be unchanged, so that the adjustment effect is controllable and optimal. If the maximum force of the wind on the fan blade still cannot meet the change of the frequency, the brake system needs to be used to increase the conversion of the wind force to fully ensure the safety and stability of the grid connection.

[0115] Compared with the existing frequency regulation method of the new energy station, the stability of the grid connection frequency regulation is improved.

[0116] The above are preferred embodiments of the present application, and do not limit the protection scope of the present application. Therefore, any equivalent changes made according to the structure, shape, principle of the present application should be covered within the protection scope of the present application.

Claims

1. A frequency modulation method for a new energy station, characterized in that, The method comprises the following steps: S1, acquiring the grid frequency requirement of the grid connection point and the power generation power of the wind power generator, and grouping the wind power generators in the wind power station according to the grid frequency requirement and the power generation power to determine the wind power generators required to be connected to each grid connection point; S2, based on the grid frequency requirement, the wind power generators connected to the grid connection point are regulated to determine the initial state of each wind power generator on the grid connection point, and the speed reference data and the wind reference data are obtained; S3, the speed of the wind power generator is monitored to obtain the speed monitoring data, and the environmental information of the wind power generator is monitored to obtain the wind monitoring data; S4, the wind monitoring data is monitored for wind data change, the change time point is obtained, and the speed monitoring data is judged based on the change time point to determine whether the speed of the wind power generator at the corresponding time point changes, if the speed changes, the wind data is marked to obtain the wind marked data; S5, the wind marked data is analyzed to determine the wind power conversion sensitivity under different wind power generator states; S6, the output frequency of the grid connection point is monitored to obtain the frequency monitoring data, the time point when the speed changes is determined based on the speed monitoring data, the speed time point is obtained, and the output frequency of the grid connection point at the corresponding time point is determined based on the speed time point to determine whether the output frequency changes; S7, if the output frequency changes, the speed data is marked to obtain the speed marked data, the speed marked data is analyzed to determine the sensitivity of the output frequency under different speeds, and the speed conversion sensitivity is obtained; S8, based on the wind power conversion sensitivity and the speed conversion sensitivity, the overall sensitivity of the grid connection point is obtained, the overall fluctuation range of the wind power generator is determined based on the overall sensitivity, and the wind power generator is adjusted based on the overall fluctuation range.

2. The frequency modulation method of a new energy station according to claim 1, characterized in that: Step S4 comprises: The speed monitoring data and the speed reference data are difference calculated to obtain the speed fluctuation value, and the speed fluctuation value is counted based on the time data to obtain the speed fluctuation curve; The yaw data of the wind power generator is acquired, and based on the yaw data and the wind direction data in the wind monitoring data, the deviation data between the wind power generator and the wind direction is determined; The fan working data of the wind power generator is acquired, and based on the fan working data, the deviation data and the wind speed data in the wind monitoring data, the force of the wind on the fan under different wind monitoring data is determined to obtain the wind data; The wind data and the wind reference data are difference calculated to obtain the wind fluctuation value, and based on the built-in first comparison threshold, the wind fluctuation value is filtered to obtain the wind fluctuation value exceeding the first comparison threshold, and the time point corresponding to the wind fluctuation value is read to obtain the wind change time point; Based on the wind change time point, the speed fluctuation value of the speed fluctuation curve is read to obtain the to-be-judged speed fluctuation data, and the to-be-judged speed fluctuation data is compared with the built-in second comparison threshold, the wind change time point corresponding to the to-be-judged speed fluctuation data greater than the second comparison threshold is marked to obtain the marked time point; Based on the marked time point, the wind fluctuation value is marked to obtain the wind marked data.

3. The frequency modulation method of a new energy station according to claim 2, characterized in that: Step S5 comprises: S51, determine the speed change amount corresponding to the time point based on the marking time point; S52, divide the wind mark data based on the fan working data at the change time point, determine the wind mark data under the same fan working data, and mark it as a state mark group; S53, draw a wind speed change curve between the wind mark data and the speed change amount in the state mark group; S54, determine the change relationship between wind and speed under different fan working states based on the wind speed change curve, and determine the wind conversion sensitivity under different fan working states based on the change relationship.

4. The frequency modulation method of a new energy station according to claim 3, characterized in that: Step S54 includes: Based on the wind speed change curve, the change relationship between wind and speed under different fan working states is obtained and marked as wind change relationship; Based on the wind change relationship, the speed monitoring data is calculated to determine the change amount of wind when the speed changes by one standard speed unit, and the minimum wind change amount is obtained; Based on the minimum wind change amount, the wind data is matched to determine whether there is a case where the change amount is the minimum wind change amount in the wind data. If it is determined that there is, the speed monitoring data is matched according to the time point corresponding to the minimum wind change amount to determine whether the speed monitoring data has changed; If it is determined that the change has occurred, the standard unit is taken as the minimum change unit of the speed change, and the corresponding wind conversion sensitivity is constructed based on the minimum change unit of the speed and the wind change relationship; If it is determined that the speed monitoring data has not changed, the change amount of wind when the speed changes by two standard speed units is determined according to the wind change relationship until the time point corresponding to the wind change amount is matched successfully with the speed monitoring data.

5. The frequency modulation method of a new energy station according to claim 4, characterized in that: Step S7 includes: Based on the built-in frequency fluctuation threshold, the frequency monitoring data is filtered to obtain the time point at which the output frequency fluctuation is greater than the frequency fluctuation threshold, and the time point is marked as a frequency fluctuation time point; Based on the frequency fluctuation time point, the speed monitoring data is read to obtain the speed data to be judged; The speed change amount is determined by difference calculation between the speed data to be judged and the speed reference data, and the frequency change amount is obtained by difference calculation between the frequency monitoring data at the frequency fluctuation time point and the frequency fluctuation threshold; The speed frequency group data is obtained by corresponding grouping of the speed change amount and the frequency change amount; The speed change relationship is determined by mathematical statistics of the multiple speed frequency group data, and the speed monitoring data and the frequency monitoring data are verified based on the speed change relationship and the built-in standard frequency unit to determine the minimum change amount between the speed and the frequency, and the speed conversion sensitivity between the speed and the frequency is determined based on the minimum change amount.

6. The frequency modulation method of a new energy station according to claim 5, characterized in that: Step S8 includes: S81, based on the minimum change amount of the speed in the wind conversion sensitivity and the minimum change amount of the frequency in the speed conversion sensitivity, the wind conversion sensitivity and the speed conversion sensitivity are coupled to obtain the overall sensitivity between wind and frequency; S82, determine the fluctuation range of the wind acting on the wind turbine according to the minimum change amount of the frequency in the overall sensitivity to obtain the overall fluctuation range; S83, record the wind monitoring data at the current time point as current wind data, record the fan working data at the current time point as real-time state data, judge the current wind data based on the real-time state data, and determine the current wind force acting on the wind turbine by the current wind data; S84, judge the frequency monitoring data to determine the frequency change trend, judge the working state of the wind turbine based on the frequency change trend, the current wind force and the overall fluctuation range, and obtain the adjustment data; S85, adjust the working state of the wind turbine to the data edge of the overall fluctuation range based on the adjustment data.

7. The frequency modulation method of a new energy station according to claim 6, characterized in that: Step S84 includes: S841, if the frequency change trend is a downward trend, calculate the difference value of the current wind force according to the upper limit value of the overall fluctuation range to obtain first adjustment difference data; S842, obtain the maximum conversion coefficient of the fan, and determine the maximum wind force that can be reached based on the current wind data and the maximum conversion coefficient; S843, compare the maximum wind force with the first adjustment difference data to determine whether the maximum wind force meets the requirements of the first adjustment difference data, if it is determined that the requirements of the first adjustment difference data are met, determine the first adjustment data of the fan blade of the wind turbine under the current wind data according to the first adjustment difference data; S844, if it is determined that the requirements of the first adjustment difference data are not met, obtain the braking coefficient of the braking system, and adjust the braking coefficient of the braking system according to the difference between the first adjustment difference data and the maximum wind force to obtain second adjustment data; S845, if the frequency change trend is an upward trend, calculate the difference value of the current wind force according to the lower limit value of the overall fluctuation range to obtain second adjustment difference data, and adjust the wind turbine according to the second adjustment difference data to obtain third adjustment data of the wind turbine.

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