Water-turbine generator set AGC real-time control strategy applied to electric power auxiliary service market

Abstract

The invention discloses a water-turbine generator set AGC real-time control strategy applied to an electric power auxiliary service market, and relates to the technical field of electric power system automation control. Data acquisition and monitoring: operating data of the water turbine are acquired through a flow sensor, a water head sensor, a guide vane opening sensor and a power sensor which are mounted on the water turbine, and nonlinear characteristics of the water turbine, such as nonlinearity of a flow-water head-power curve and a nonlinear relation between guide vane opening and output, are deeply analyzed; the influence of the characteristics on unit operation can be accurately captured, the AGC control signal is corrected and compensated by adopting a nonlinear compensation control technology, and the control precision is remarkably improved, which means that the water turbine can be accurately controlled under different working conditions, such as different combinations of flow, water head and guide vane opening degrees. And the method can operate according to the expected target output more accurately, so that the stability and the reliability of the whole power system are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power system automation control, and in particular to an AGC real-time control strategy for a hydro-generator set applied to the power auxiliary service market. Background Art

[0002] With the continuous development of the power market, the power auxiliary service market has gradually become an important part of the power system. As one of the main power generation equipment in the power system, the stable and efficient operation of the hydro-turbine generator set is of great significance to ensure the safe and stable operation of the power system. However, the operating characteristics of the hydro-turbine generator set are affected by many factors, among which the nonlinear characteristics of the turbine are particularly significant. These characteristics make the control of the turbine complex and difficult to be precise. Therefore, studying a control strategy that can accurately reflect the nonlinear characteristics of the turbine and effectively compensate for it is of great significance to improve the operating efficiency and stability of the hydro-turbine generator set.

[0003] Traditional turbine control strategies are mostly designed based on linear models, which are difficult to accurately reflect the nonlinear characteristics of turbines. Therefore, in actual operation, these strategies often cannot achieve the expected control effect, especially when the turbine is in complex working conditions, the limitations of traditional control strategies are more obvious. In addition, traditional technologies also have some shortcomings in the compensation control of nonlinear characteristics of turbines. At the same time, for the nonlinear relationship between guide vane opening and output, traditional methods also lack effective compensation means, making it difficult for turbines to achieve the expected output under different working conditions. Although some traditional technologies attempt to correct the power command output by the AGC system by establishing a nonlinear compensation function, due to the lack of in-depth nonlinear characteristic analysis and precise compensation function design, the compensation effect is limited and it is difficult to meet actual operation needs.

[0004] Therefore, a real-time AGC control strategy for hydro-turbine generator sets applied to the power auxiliary service market is developed. By deeply analyzing the nonlinear characteristics of the turbine and using nonlinear compensation control technology to correct and compensate the AGC control signal, the control accuracy and stability are improved, so that the turbine can operate according to the expected target output under different working conditions. Summary of the invention

[0005] The purpose of the present invention is to make up for the deficiencies of the prior art and to provide a real-time AGC control strategy for a hydro-turbine generator set applied to the power auxiliary service market. The strategy can realize compensatory control of the nonlinear characteristics of the turbine through data acquisition and monitoring, nonlinear characteristic analysis, AGC control signal correction, load distribution and regulation, real-time feedback and adjustment, and interaction with the power auxiliary service market, thereby improving the control accuracy and response speed, optimizing the operating efficiency of the hydro-turbine generator set, and providing the power auxiliary service market with a more reliable and efficient regulation capability.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a real-time control strategy of AGC of a hydro-generator set applied to the power auxiliary service market, the specific steps of the control strategy are: S100, data collection and monitoring: collect the operation data of the turbine through the flow sensor, water head sensor, guide vane opening sensor and power sensor installed on the turbine, and monitor the frequency, load demand and active power target value issued by the superior dispatcher of the power system; S200, nonlinear characteristic analysis: extract flow, head and power data from the collected turbine operation data, group the data according to different head intervals, analyze the nonlinear characteristics of the flow-head-power curve and the nonlinear relationship between the guide vane opening and the output, and establish a nonlinear compensation function to correct and compensate the AGC control signal; The flow-head-power curve drawing and analysis in S200: for each head interval, the curve is drawn with the flow as the horizontal coordinate and the power as the vertical coordinate, the slope between two adjacent points is calculated by the five-point difference method, the law of the slope changing with the flow is observed, the concavity and convexity of the curve is judged by the second-order derivative, the difference between the curves of different head intervals is compared, the difference in shape, slope, and concavity of the flow-head-power curves drawn in different head intervals is observed, and the influence of the head on the nonlinear characteristics is understood; Drawing and analyzing the guide vane opening and output relationship curve in S200: extracting the guide vane opening and output data from the collected operation data, screening and preprocessing the data, drawing a curve with the guide vane opening as the horizontal coordinate and the output as the vertical coordinate, analyzing the change in the slope of the curve in different opening intervals, understanding the law of the change in output with the guide vane opening, determining the key turning point of the curve, finding the point where the slope of the curve suddenly changes by observing the change in the shape of the curve, studying the change in the curve under different working conditions, and analyzing the influence of the working conditions on the nonlinear relationship; The nonlinear compensation function in S200 is established: for the nonlinear characteristics of the flow-head-power curve, a compensation function is established by using a multivariate nonlinear regression analysis method, and the formula is: ,in is power, For flow, For water head, and is the coefficient to be determined; for the nonlinear relationship between the guide vane opening and the output, a piecewise function is used to establish a compensation function. In the interval, the relationship between output and opening is expressed as: , when the guide vane opening is In the interval, the relationship between output and opening is expressed as: ,in is the guide vane opening, and For different ranges of output, and is the coefficient; S300, AGC control signal correction: Substitute the power command output by the AGC system into the above nonlinear compensation function for correction. When the correction is based on the flow-head-power curve, the formula is: ,in and is the currently collected flow and head value. When the guide vane opening is corrected based on the relationship between the guide vane opening and the output, In the interval, the relationship between output and opening is expressed as: , when the guide vane opening is In the interval, the relationship between output and opening is expressed as: ,in is the guide vane opening, and For different ranges of output, and The coefficient is used to obtain the corrected power command. Considering the operating constraints of the turbine, the corrected power command is checked. If it does not meet the requirements, it is corrected again. S400, load distribution and regulation: According to the revised power command and the load demand of the power system, the priority gradient allocation algorithm is used to determine the number of operating turbine generator sets, the combination of operating units, and the load distribution between units. At the same time, the upstream water inflow and water level, downstream water discharge and water level, and reservoir capacity of the reservoir are considered, and the load of the units is adjusted based on the principle of economic operation; S500, real-time feedback and adjustment: Feedback the actual operation data of the hydro-generator set to the AGC system in real time, and adjust and optimize the AGC control strategy based on the feedback data; S600, interacting with the power auxiliary service market: According to the rules and requirements of the power auxiliary service market, the available capacity and regulation capability of the hydro-generator set are reported to the market operation agency, the regulation instructions issued by the market operation agency are received, and the AGC control strategy in the above steps is responded and executed.

[0007] Furthermore, the five-point difference method is used in S200 to calculate the slope change rate of the flow-head-power curve. For the flow-head-power curve, the flow is , the power is , select five consecutive points on the curve, namely: , , , use the five-point difference method to calculate the midpoint The slope at , the formula is: ,and .

[0008] Furthermore, in S200, the concavity of the flow-head-power curve is determined according to the second-order derivative, and the function expression of the flow-head-power curve is assumed to be: ,right Find the first-order derivative , the formula is: ,in is the flow step size, is a certain flow value, with respect to the first-order derivative Derivative again to get the second-order derivative , the formula is: According to the second-order derivative The value of determines the concavity of the curve. The curve is It is a concave function, and the curve bends upward near this point. The curve is It is a convex function near this point, and the curve bends downward.

[0009] Furthermore, in S200, the guide vane opening range is determined by the slope change rate, and the guide vane opening is , output is , in a certain interval, select two adjacent points and , slope The calculation formula is: , when the slope change rate exceeds a certain set threshold , this point can be used as the critical point for interval division, where and is the slope of the adjacent interval, and is the adjacent guide vane opening value.

[0010] Furthermore, in S300, based on the correction of the flow-head-power curve, the original power command output by the AGC system is obtained. , and obtain the current flow of the turbine and water head Data will , as well as Substitute the nonlinear compensation function of the flow-head-power curve: , calculate the corrected power command , obtain the relevant parameters of the unit vibration zone, including the frequency range of the vibration zone And the corresponding power range , according to the current operating frequency of the turbine and the calculated corrected power command , judge whether the vibration zone conditions are met. The corrected power meets the instruction requirements and does not need to be readjusted. The corrected power instruction does not meet the vibration zone requirements and is adjusted using linear interpolation.

[0011] Furthermore, the power instruction corrected in S300 does not meet the vibration zone requirements, and is adjusted using a linear interpolation method, and the vibration zone boundary power value is set to , then the adjusted power command The calculation formula is: ,in is the operating frequency of the front turbine, is the frequency range of the vibration zone, The original power command output by the AGC system .

[0012] Furthermore, in S300, based on the correction of the relationship between the guide vane opening and the output, the current guide vane opening is obtained through the guide vane opening sensor. The data of the guide vane opening Compare with the predetermined guide vane opening range to determine In the interval where the guide vane opening is located, select the corresponding compensation function. exist Interval, select function: , exist Interval, select function: , the current guide vane opening Substitute into the selected compensation function and calculate the corrected power instruction .

[0013] Furthermore, the S400 determines the number of operating hydro-generator sets, the combination of operating sets, and the load distribution between sets according to the priority gradient allocation algorithm based on the corrected power command and the load demand of the power system. For the first priority set, the load it can carry is: , for the second priority unit, the load it can carry is: ,in is the corrected total power command, is the minimum power limit of the unit, is the total number of units participating in AGC, Pnj is the total output of units not participating in AGC, and These are the maximum power limits for the first-priority units and the second-priority units respectively.

[0014] Furthermore, in S500, the error between the actual output and the expected output of the hydro-generator set is calculated by an error calculation formula, and the formula is: ,in For actual contribution, Contribute to expectations, The error threshold is set to trigger the adjustment of the load distribution algorithm and the nonlinear compensation function.

[0015] Furthermore, in S500, the error threshold is set from the perspective of economic operation, and the power generation efficiency loss caused by the error exceeds a certain economic threshold. , assuming the relationship between power generation efficiency and power is , the actual output is , the expected output is: ,when When is the cost per unit of electricity, by adjusting and The difference between the two values ​​determines the appropriate error threshold .

[0016] Compared with the existing technology, the AGC real-time control strategy of the hydro-generator set applied to the power auxiliary service market has the following beneficial effects: 1. The present invention can accurately capture the impact of these characteristics on the operation of the unit by deeply analyzing the nonlinear characteristics of the turbine, such as the nonlinearity of the flow-head-power curve and the nonlinear relationship between the guide vane opening and the output. By adopting nonlinear compensation control technology, the AGC control signal is corrected and compensated, which significantly improves the control accuracy. This means that the turbine can operate more accurately according to the expected target output under different working conditions, such as different combinations of flow, head and guide vane opening, thereby improving the stability and reliability of the entire power system.

[0017] 2. The present invention establishes a nonlinear compensation function to make real-time corrections to the power command output by the AGC system. This correction is based on the actual operating data of the current turbine, such as flow rate, head and guide vane opening, so as to ensure that the power command is more in line with the actual operating characteristics of the turbine. This real-time correction and compensation method not only improves the control accuracy, but also enhances the response speed and regulation ability of the turbine to load changes. In actual operation, this helps to reduce output deviation and energy waste caused by inaccurate control, and further improves the economy and efficiency of the power system.

[0018] Other advantages, objectives and features of the present invention will be set forth in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be taught from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 It is a flow chart of a real-time control strategy of AGC for hydro-generator units applied in the power auxiliary service market; Figure 2 Flowchart of the nonlinear characteristics analysis steps. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example 1

[0022] A large hydropower station participates in the power auxiliary service market and undertakes the tasks of grid frequency regulation and peak load regulation. It needs to meet the precise control requirements of power generation in the power system and adapt to changes in reservoirs and water inflows as well as market regulations.

[0023] Data collection and monitoring, flow measurement through flow sensors , the head sensor measures the water head , the guide vane opening sensor measures the guide vane opening , power sensors measure power ,At the same time, the power system frequency, load demand and active power target value issued by the superior dispatcher are monitored.

[0024] Nonlinear characteristic analysis, flow-head-power curve analysis, draw a curve in a certain head range, and use the five-point difference method to calculate the slope between two adjacent points ,and , let the function expression of flow-head-power curve be , the first-order derivative is: , the second-order derivative is: , judge the concavity of the curve and establish a nonlinear compensation function: , determine the regression coefficient and exponential coefficient, analyze the relationship between the guide vane opening and the output, draw the curve, analyze the slope change, and set the guide vane opening to , output is , in a certain interval, select two adjacent points and , slope , determine the key turning point of the curve and establish a piecewise function model within a certain opening range. When the interval is , when the guide vane opening is During the interval, .

[0025] AGC control signal correction, based on flow-head-power curve correction, original power command , substitute into the nonlinear compensation function: , calculated , obtain the frequency range and corresponding power range of the unit vibration zone, and judge whether it meets the vibration zone conditions. The corrected power meets the vibration zone conditions and does not need to be readjusted. The corrected power instruction does not meet the vibration zone requirements and is adjusted using linear interpolation. Set the vibration zone boundary power value to , then the adjusted power command The calculation formula is: ,in is the operating frequency of the front turbine, is the frequency range of the vibration zone, The original power command output by the AGC system , based on the correction of the relationship between the guide vane opening and the output, the guide vane opening is determined In a certain interval, according to the interval where the guide vane opening is located, select the corresponding compensation function. exist interval, then select the function , exist interval, then select the function , the current guide vane opening Substitute into the selected compensation function and calculate the corrected power instruction .

[0026] Load distribution and regulation, corrected total power command , minimum unit power limit , the total number of sites participating in AGC , the total output of the units not participating in AGC is Pnj, the maximum power limit of the first priority unit , the second priority unit maximum power limit For the first priority units and the second priority units, the water inflow and water level conditions upstream of the reservoir are considered and the unit load is adjusted according to the principle of economic operation.

[0027] Real-time feedback and adjustment: The actual operating data of the turbine generator set is fed back to the AGC system in real time through sensors, including the actual head, flow, guide vane opening, power parameters and the operating status information of the unit, and the difference between the actual power and the expected output is fed back. , set the error threshold O value ,when , no adjustment is made.

[0028] Interact with the power auxiliary service market, calculate the available capacity of the hydro-turbine generator set, report the information of available capacity and regulation capability to the market operation agency, receive the regulation instructions issued by the market operation agency, and respond and execute according to the AGC control strategy.

[0029] In summary, this large-scale hydropower station embodiment demonstrates the effective application of the present invention in practice. Through precise data collection, including parameters of flow, head, guide vane opening and power, a basis is provided for subsequent analysis. Nonlinear characteristic analysis accurately grasps the relationship between various parameters and establishes a reasonable compensation function. AGC control signal correction comprehensively considers multiple factors to improve the accuracy of power instructions. Load distribution and regulation take into account unit characteristics and reservoir conditions to achieve economic operation. Real-time feedback and adjustment mechanisms ensure system stability. Interaction with the power auxiliary service market enables hydropower stations to better adapt to market demand, thereby improving power generation efficiency and support capabilities for the power grid as a whole. Example 2

[0030] A medium-sized hydropower station operates in the power auxiliary service market. It needs to maintain efficient and stable operation under different head and flow conditions, meet the power regulation needs of the power grid, and reasonably adjust the unit load according to the changes in reservoir water level.

[0031] Data collection and monitoring: flow sensors are installed at the water inlet of the turbine to measure the flow rate. The water head sensor is installed near the runner chamber to measure the water head. , the guide vane opening sensor measures the guide vane opening Power sensor measures power At the same time, the power system frequency, load demand and active power target value issued by the superior dispatcher are monitored.

[0032] Nonlinear characteristic analysis, flow-head-power curve analysis, grouping data according to different head intervals, such as selecting a specific head interval for detailed analysis, drawing the flow-head-power curve within this interval, and using the five-point difference method to calculate the slope between two adjacent points is: ,and , select appropriate points on the curve for calculation, and use this method to more accurately analyze the changing trend of the curve in this interval. Suppose the function expression of the flow-head-power curve is , and calculate its first-order derivative as: , the second-order derivative is: , in order to judge the concavity of the curve, through these calculations, we can deeply understand the nonlinear relationship between flow rate, head and power, and establish a nonlinear compensation function , the regression coefficient and exponential coefficient are determined by multivariate nonlinear regression analysis, the guide vane opening and output relationship analysis is performed, the guide vane opening and output data are extracted from the collected operation data, the curve is drawn, and the slope change of the curve in different opening ranges is analyzed. Assume that the guide vane opening is , output is , in a certain interval, select two adjacent points, and , slope By analyzing the slopes of different intervals, it is determined that the key turning point of the curve is within a certain opening interval, such as In the interval, a piecewise function model is established. When the guide vane opening is in a certain interval, such as When the coefficient is determined by data fitting , , , , when the guide vane opening is in another range such as The values ​​of these coefficients are also determined by data fitting.

[0033] AGC control signal correction, based on the correction of flow-head-power curve, obtains the original power command output by the AGC system , and the current flow and water head Substitute the value of into the nonlinear compensation function: , calculated , obtain the frequency range and corresponding power range of the unit vibration zone, check the current operating frequency and Is it within the vibration zone? If it does not meet the vibration zone requirements, use linear interpolation to adjust the vibration zone boundary power value. , then the adjusted power command The calculation formula is: , based on the correction of the relationship between the guide vane opening and the output, obtain the current guide vane opening The value of , determine its interval, set In a certain range (such as , select the corresponding function ,Will Substituting this function into the calculation, we get .

[0034] Load distribution and regulation, determine the corrected total power command , minimum unit power limit , the total number of units participating in AGC , the total output of the units not participating in AGC is Pnj, the maximum power limit of the first priority unit , the second priority unit maximum power limit , for the first priority unit, by comparing and The size of the first priority unit determines the load that the first priority unit can bear. For the second priority unit, the load borne by the first priority unit is considered. Based on the above and other relevant factors, the load of the second priority unit is determined, and the water inflow and water level upstream of the reservoir are taken into consideration. According to the principle of economic operation, the unit load is adjusted. If the upstream water inflow is moderate and the water level is stable, the current load distribution is maintained. If the water inflow increases or the water level changes significantly, the unit load is adjusted.

[0035] Real-time feedback and adjustment: The actual operating data of the turbine generator set is fed back to the AGC system in real time through sensors, including the actual head, flow, guide vane opening, power parameters and the operating status information of the unit. After obtaining the feedback data, the difference between the actual power and the expected output is calculated. , set the error threshold ,when , no adjustment is made.

[0036] Interact with the power auxiliary service market, calculate the available capacity of the hydro-turbine generator set, report the information of available capacity and regulation capability to the market operation agency, receive the regulation instructions issued by the market operation agency, and respond and execute according to the AGC control strategy.

[0037] In summary, this medium-sized hydropower station embodiment embodies the practicality of the invention, data collection meets the requirements, and provides data support for system operation. The nonlinear characteristic analysis reveals the relationship between flow-head-power and guide vane opening and output, and establishes an effective compensation function. The AGC control signal is corrected reasonably, considering the vibration zone conditions, and the load distribution and adjustment are based on actual conditions to ensure the economy of unit operation and reservoir utilization. Real-time feedback and adjustment can handle errors in a timely manner, and interaction with the market enables the unit to respond to market instructions. While meeting the power regulation needs of the power grid, this embodiment improves the adaptability and operating efficiency of the hydropower station in the power auxiliary service market.

[0038] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and range of equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A real-time control strategy for AGC of a hydro-generator set applied to the power auxiliary service market, characterized in that: The specific steps of this control strategy are: S100, data collection and monitoring: collect the operation data of the turbine through the flow sensor, water head sensor, guide vane opening sensor and power sensor installed on the turbine, and monitor the frequency, load demand and active power target value issued by the superior dispatcher of the power system; S200, nonlinear characteristic analysis: extract flow, head and power data from the collected turbine operation data, group the data according to different head intervals, analyze the nonlinear characteristics of the flow-head-power curve and the nonlinear relationship between the guide vane opening and the output, and establish a nonlinear compensation function to correct and compensate the AGC control signal; The flow-head-power curve drawing and analysis in S200: for each head interval, the curve is drawn with the flow as the horizontal coordinate and the power as the vertical coordinate, the slope between two adjacent points is calculated by the five-point difference method, the law of the slope changing with the flow is observed, the concavity and convexity of the curve is judged by the second-order derivative, the difference between the curves of different head intervals is compared, the difference in shape, slope, and concavity of the flow-head-power curves drawn in different head intervals is observed, and the influence of the head on the nonlinear characteristics is understood; Drawing and analyzing the guide vane opening and output relationship curve in S200: extracting the guide vane opening and output data from the collected operation data, screening and preprocessing the data, drawing a curve with the guide vane opening as the horizontal coordinate and the output as the vertical coordinate, analyzing the change in the slope of the curve in different opening intervals, understanding the law of the change in output with the guide vane opening, determining the key turning point of the curve, finding the point where the slope of the curve suddenly changes by observing the change in the shape of the curve, studying the change in the curve under different working conditions, and analyzing the influence of the working conditions on the nonlinear relationship; The nonlinear compensation function in S200 is established: for the nonlinear characteristics of the flow-head-power curve, a compensation function is established by using a multivariate nonlinear regression analysis method, and the formula is: ,in is power, For flow, For water head, and is the coefficient to be determined; for the nonlinear relationship between the guide vane opening and the output, a piecewise function is used to establish a compensation function. In the interval, the relationship between output and opening is expressed as: , when the guide vane opening is In the interval, the relationship between output and opening is expressed as: ,in is the guide vane opening, and For different ranges of output, and is the coefficient; S300, AGC control signal correction: Substitute the power command output by the AGC system into the above nonlinear compensation function for correction. When the correction is based on the flow-head-power curve, the formula is: ,in and is the currently collected flow and head value. When the guide vane opening is corrected based on the relationship between the guide vane opening and the output, In the interval, the relationship between output and opening is expressed as: , when the guide vane opening is In the interval, the relationship between output and opening is expressed as: ,in is the guide vane opening, and For different ranges of output, and The coefficient is used to obtain the corrected power command. Considering the operating constraints of the turbine, the corrected power command is checked. If it does not meet the requirements, it is corrected again. S400, load distribution and regulation: According to the revised power command and the load demand of the power system, the priority gradient allocation algorithm is used to determine the number of operating turbine generator sets, the combination of operating units, and the load distribution between units. At the same time, the upstream water inflow and water level, downstream water discharge and water level, and reservoir capacity of the reservoir are considered, and the load of the units is adjusted based on the principle of economic operation; S500, real-time feedback and adjustment: Feedback the actual operation data of the hydro-generator set to the AGC system in real time, and adjust and optimize the AGC control strategy based on the feedback data; S600, interacting with the power auxiliary service market: According to the rules and requirements of the power auxiliary service market, the available capacity and regulation capability of the hydro-generator set are reported to the market operation agency, the regulation instructions issued by the market operation agency are received, and the AGC control strategy in the above steps is responded and executed.

2. According to claim 1, a hydroelectric generator AGC real-time control strategy applied to the power auxiliary service market is characterized in that: In S200, the five-point difference method is used to calculate the slope change rate of the flow-head-power curve. For the flow-head-power curve, the flow is , the power is , select five consecutive points on the curve, namely: , , , use the five-point difference method to calculate the midpoint The slope at , the formula is: ,and .

3. The AGC real-time control strategy for a hydro-generator set applied to the power auxiliary service market according to claim 1 is characterized in that: In the step S200, the concavity of the flow-head-power curve is determined according to the second-order derivative, and the function expression of the flow-head-power curve is assumed to be: ,right Find the first-order derivative , the formula is: ,in is the flow step size, is a certain flow value, with respect to the first-order derivative Derivative again to get the second-order derivative , the formula is: According to the second-order derivative The value of determines the concavity of the curve. The curve is It is a concave function, and the curve bends upward near this point. The curve is It is a convex function near this point, and the curve bends downward.

4. According to claim 1, a hydroelectric generator AGC real-time control strategy applied to the power auxiliary service market is characterized in that: In S200, the guide vane opening range is determined by the slope change rate, and the guide vane opening is assumed to be , output is , in a certain interval, select two adjacent points and , slope The calculation formula is: , when the slope change rate exceeds a certain set threshold , this point can be used as the critical point for interval division, where and is the slope of the adjacent interval, and is the adjacent guide vane opening value.

5. The AGC real-time control strategy for a hydro-generator set applied to the power auxiliary service market according to claim 1 is characterized in that: In S300, based on the correction of the flow-head-power curve, the original power command output by the AGC system is obtained. , and obtain the current flow of the turbine and water head Data will , as well as Substitute the nonlinear compensation function of the flow-head-power curve: , calculate the corrected power command , obtain the relevant parameters of the unit vibration zone, including the frequency range of the vibration zone And the corresponding power range , according to the current operating frequency of the turbine and the calculated corrected power command , judge whether the vibration zone conditions are met. The corrected power meets the instruction requirements and does not need to be readjusted. The corrected power instruction does not meet the vibration zone requirements and is adjusted using linear interpolation.

6. The AGC real-time control strategy for a hydro-generator set applied to the power auxiliary service market according to claim 5 is characterized in that: The power instruction corrected in S300 does not meet the vibration zone requirements, and is adjusted using linear interpolation. The vibration zone boundary power value is set to , then the adjusted power command The calculation formula is: ,in is the operating frequency of the front turbine, is the frequency range of the vibration zone, The original power command output by the AGC system .

7. The AGC real-time control strategy for a hydro-generator set applied to the power auxiliary service market according to claim 1 is characterized in that: In the step S300, based on the correction of the relationship between the guide vane opening and the output, the current guide vane opening is obtained through the guide vane opening sensor. The data of the guide vane opening Compare with the predetermined guide vane opening range to determine In the interval where the guide vane opening is located, select the corresponding compensation function. exist Interval, select function: , exist Interval, select function: , the current guide vane opening Substitute into the selected compensation function and calculate the corrected power instruction .

8. The AGC real-time control strategy for a hydro-generator set applied to the power auxiliary service market according to claim 1 is characterized in that: The S400 determines the number of operating hydro-generator sets, the combination of operating sets and the load distribution between sets according to the priority gradient allocation algorithm based on the corrected power command and the load demand of the power system. For the first priority set, the load it can carry is: , for the second priority unit, the load it can carry is: ,in is the corrected total power command, is the minimum power limit of the unit, is the total number of units participating in AGC, Pnj is the total output of units not participating in AGC, and These are the maximum power limits for the first-priority unit and the second-priority unit respectively.

9. The AGC real-time control strategy for a hydro-generator set applied to the power auxiliary service market according to claim 1 is characterized in that: In S500, the error between the actual output and the expected output of the hydro-generator set is calculated by an error calculation formula, which is: ,in For actual contribution, Contribute to expectations, The error threshold is set to trigger the adjustment of the load distribution algorithm and the nonlinear compensation function.

10. The AGC real-time control strategy for a hydro-generator set applied to the power auxiliary service market according to claim 9, characterized in that: In S500, the error threshold is determined from the perspective of economic operation. The power generation efficiency loss caused by the error exceeds a certain economic threshold. , assuming the relationship between power generation efficiency and power is , the actual output is , the expected output is: ,when When is the cost per unit of electricity, by adjusting and The difference between the two values ​​determines the appropriate error threshold .

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