Source-network collaborative primary frequency modulation optimization method and system based on load demand

Abstract

The invention relates to the technical field of power grid system frequency modulation, and particularly discloses a source-network cooperation primary frequency modulation optimization method and system based on load demand, and the method comprises the steps: obtaining key parameter information of a power grid and a unit, and determining index parameter information for evaluating the frequency modulation performance of the unit according to the key parameter information, determining the index parameter information and quantizing the index parameter information based on a coding analysis method, determining weak index parameters of the unit in the frequency modulation process, determining a deviation value between actual and theoretical integral electric quantities of the integral electric quantity according to the weak index parameters, and superposing the deviation value to the frequency modulation compensation quantity of the unit to obtain the frequency modulation compensation quantity of the unit. The frequency difference peak value and the frequency modulation duration in the closed-loop adjustment process are obtained, and if the frequency difference peak value is smaller than the preset frequency difference threshold value and the frequency modulation duration is larger than the preset duration threshold value, the small frequency difference response and the later response after frequency modulation are compensated, so that the frequency modulation response speed and performance of the unit are improved. And the frequency stability of the power grid is effectively improved.

Description

Technical Field

[0001] The present application relates to the technical field of power grid system frequency regulation, and in particular to a method and system for optimizing source-grid coordinated primary frequency regulation based on load demand. Background Art

[0002] The primary frequency control scheme of traditional thermal power units mainly relies on the regulation relationship between the unit's speed signal and the electrical frequency signal. However, this frequency control scheme usually has the problem of delayed frequency response, that is, when the frequency changes, the unit cannot respond immediately, thus affecting the rapid stabilization of the grid frequency. Secondly, under small frequency difference conditions, the regulation effect of traditional frequency regulation methods is not obvious, especially when the grid frequency fluctuates slightly or changes slowly, the unit's response is insufficient, resulting in the inability to effectively maintain frequency stability.

[0003] One of the key technologies of source-grid coordinated frequency regulation is how to achieve coordination and optimization between the power generation end and the load end. The power generation end participates in frequency regulation through power electronic devices and energy storage systems, while the load end regulates the load through intelligent control and demand response technology. In actual applications, it is found that the integral power is one of the main factors affecting the frequency regulation performance of the unit. How to achieve source-grid coordinated frequency regulation and automatically analyze the integral power index from many indicators, and when the integral power is the most prominent influencing indicator, how to adjust and solve the problems of insufficient response to small frequency differences and insufficient response after long-term frequency regulation, so as to avoid over-regulation or reverse regulation, and at the same time improve the speed and accuracy of frequency regulation response, and effectively improve the frequency stability of the power grid. Summary of the invention

[0004] The present application aims to solve at least one of the problems existing in the above-mentioned prior art. Based on this, a source-grid coordinated primary frequency regulation optimization method and system based on load demand are proposed to realize automated analysis of the frequency regulation performance of the unit, while adjusting the frequency response capabilities of the power generation end and the load end, accurately adjusting the frequency regulation amplitude of the unit, avoiding over-regulation or reverse regulation, and improving the speed and accuracy of the frequency regulation response, thereby effectively improving the frequency stability of the power grid.

[0005] In a first aspect, the present application provides a method for optimizing source-network coordinated primary frequency regulation based on load demand, comprising: Obtaining key parameter information of the power grid and the unit, the key parameter information including power grid frequency data, power grid power, generator unit output power and frequency modulation instructions; Determine, based on the key parameter information, index parameter information for evaluating the frequency regulation performance of the unit, wherein the index parameter information at least includes response lag time, integral power, and regulation reverse direction; Determining the index parameter information and quantifying the index parameter information based on a coding analysis method to determine weak index parameters of the unit during the frequency modulation process; According to the weakness indicator parameter, the integral power closed-loop optimization module on the CCS system side determines the deviation value between the actual integral power and the theoretical integral power, and adds the deviation value to the frequency regulation compensation amount of the unit to perform closed-loop adjustment on the output power of the unit; Obtaining a frequency difference peak value and a frequency modulation duration in a closed-loop adjustment process, and determining whether the frequency difference peak value is less than a preset frequency difference threshold and whether the frequency modulation duration is greater than a preset duration threshold; If so, the small frequency difference response and the later response after frequency modulation are compensated based on the frequency modulation compensation module.

[0006] In some examples, determining, based on the key parameter information, index parameter information for evaluating the frequency regulation performance of the unit, the index parameter information at least including response lag time, integral power, and regulation reversal, includes: Determine a response lag time according to the grid frequency data and the frequency modulation instruction, wherein the response lag time is used to characterize the delay between the time point when the output power of the generator set starts to respond to the frequency modulation instruction and the time point when the frequency modulation instruction is issued; Determine the integrated power according to the grid power and the output power of the generator set, and The reverse direction of the regulation is determined according to the frequency modulation instruction and the direction of power increase or decrease.

[0007] In some examples, determining the integrated power according to the grid power and the output power of the generator set, and determining the reverse direction of the regulation according to the frequency regulation instruction and the direction of power increase or decrease, includes: Points Power The calculation expression is: , in, is the real-time power, It is the initial power locked when the frequency modulation action passes through the dead zone. The integral start time is the frequency passing the dead zone time. K is the product coefficient; The calculation expression for adjusting the reverse direction is: , in, and They are the increments of the frequency modulation command and the actual power change, respectively. If the change directions of the two are opposite, the reverse direction is 1, otherwise it is 0; In some examples, the determining the indicator parameter information and quantifying the indicator parameter information based on a coding analysis method to determine the weak indicator parameter of the unit during the frequency modulation process includes: The response lag time, the integrated power, and the reverse direction of regulation are encoded, wherein the compliance code of each indicator in the indicator parameter information is 0, and the non-compliance code is 1, the integrated power is less than 50 and is not up to standard, the response lag time is greater than 2 and is not up to standard, and the reverse direction of regulation indicator is not up to standard when the integrated power is a negative value; Determine the encoding value corresponding to the frequency modulation result based on the binary method for the encoded indicator parameter information; Correlating the response lag time, the integrated electrical quantity and the coded value of the regulation reversal to determine a numerical parameter for quantification; Based on the numerical parameters, the pass rate of each assessment indicator after correlation is statistically calculated and the relationship between the assessment indicators is analyzed to determine the frequency regulation status information of the weak links in the frequency regulation process of the unit.

[0008] In some examples, correlating the response lag time, the integrated power, and the coded value of the adjustment reverse direction to determine a numerical parameter for quantization includes: The response lag time, the integrated power and the reverse regulation coding values ​​are binary-correlated, wherein there are five categories of numerical coding results, namely [0, 1, 3, 5, 7]. A value of 0 represents that all three indicators are qualified, a value of 1 represents that the integrated power does not meet the standard, a value of 3 represents that the integrated contribution rate is qualified but the response lag time indicator is unqualified, a value of 5 represents that the frequency regulation action is reversed but the response lag time indicator is qualified, and a value of 7 represents that all three indicators are unqualified, thereby determining the numerical parameters used for quantification.

[0009] In some examples, the step of determining the deviation between the actual and theoretical integrated power of the integrated power based on the integrated power closed-loop optimization module on the CCS system side according to the weakness indicator parameter, and adding the deviation to the frequency regulation compensation of the unit to perform closed-loop adjustment on the output power of the unit includes: The integral electric quantity theoretical value calculation expression is: , in, , In the formula, is the difference between the actual frequency and the rated frequency, is the rated power of the unit, and K is the multiplication coefficient.

[0010] In some examples, if so, compensating for the small frequency difference response and the late response after frequency modulation based on the frequency modulation compensation module includes: The calculation expression of the small frequency difference response compensation power increment is: , in, To compensate for the power increase, is the small frequency difference compensation gain coefficient, It is the difference between the actual frequency and the rated frequency; The calculation expression of the late response compensation power increment is: , in, To compensate for the power increment later, is the post-compensation gain coefficient, is the frequency modulation duration, The duration of the frequency modulation exceeds the preset frequency difference threshold.

[0011] Compared with the prior art, the technical solution provided in the first aspect of the present application includes at least the following beneficial effects or advantages: By collecting grid frequency data, grid power, generator set output power and frequency regulation instruction information at the power generation end, the response lag time, integral power and regulation reverse index for evaluating the frequency regulation performance of the unit are calculated respectively. The three major indexes are quantified by binary coding analysis method. The electronic equipment can realize automatic statistics of the occurrence frequency of different coding values ​​and index coding correlation analysis, and identify the integral power index affecting the frequency regulation performance of the unit. By adding the integral power closed-loop optimization module at the load end, the real-time calculation and adjustment of the unit frequency regulation compensation can be realized, so that the deviation between the actual power and the theoretical power is gradually reduced, and The frequency regulation index compensation increment is composed of small frequency difference response compensation and late response compensation. The frequency regulation index compensation increment is added on the CCS system side and accumulated with the original unit frequency regulation compensation. At the same time, the compensation increment is superimposed on the frequency feedback signal on the DEH system side to improve the frequency regulation amplitude under small frequency difference and the response strength after long-term frequency regulation, and enhance the comprehensive performance of unit frequency regulation. Through this compensation mechanism, the frequency regulation index compensation module ensures that the generator set can operate effectively in small frequency difference and long-term frequency regulation response scenarios, avoids insufficient frequency regulation caused by small frequency difference, and improves the frequency regulation response speed and performance of the unit, especially when the grid frequency changes smoothly but needs to be continuously adjusted, thereby avoiding over-regulation or reverse regulation, while improving the speed and accuracy of frequency regulation response, and effectively improving the frequency stability of the grid.

[0012] In a second aspect, the present application provides a source-network coordinated primary frequency modulation optimization system based on load demand, comprising: An acquisition module is configured to acquire key parameter information of the power grid and the unit, wherein the key parameter information includes power grid frequency data, power grid power, generator unit output power and frequency modulation instructions; An index parameter confirmation module is configured to determine index parameter information for evaluating the frequency regulation performance of the unit according to the key parameter information, wherein the index parameter information at least includes response lag time, integral power, and regulation reverse; A quantization coding module is configured to determine the index parameter information and quantize the index parameter information based on a coding analysis method to determine the weak index parameters of the unit during the frequency modulation process; The integral power optimization module is configured to determine the deviation value between the actual and theoretical integral power of the integral power based on the integral power closed-loop optimization module on the CCS system side according to the weak indicator parameter, and add the deviation value to the frequency regulation compensation amount of the unit to perform closed-loop adjustment on the output power of the unit; A judgment module is configured to obtain a frequency difference peak value and a frequency modulation duration in a closed-loop adjustment process, and judge whether the frequency difference peak value is less than a preset frequency difference threshold and whether the frequency modulation duration is greater than a preset duration threshold; The frequency modulation compensation module is configured to compensate for the small frequency difference response and the late response after frequency modulation based on the frequency modulation compensation module according to the judgment result of the judgment module.

[0013] In a third aspect, the present application further provides an electronic device, including: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the steps of the source-network collaborative primary frequency regulation optimization method based on load demand provided in the first aspect above.

[0014] In a fourth aspect, the present application also provides a computer-readable storage medium having computer program instructions stored thereon, and when the computer program instructions are executed by a processor, the steps of the source network collaborative primary frequency regulation optimization method based on load demand provided in the first aspect above are implemented.

[0015] It can be understood that the beneficial effects of the technical solutions provided in the second, third and fourth aspects can be found in the relevant description of the first aspect, and will not be repeated here.

[0016] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 It is a flow chart of a source network collaborative primary frequency modulation optimization method according to an embodiment of the present application; Figure 2 It is a control flow chart of a primary frequency modulation method of the prior art shown in an embodiment of the present application; Figure 3 is a control flow chart of CCS system side optimization according to an embodiment of the present application; Figure 4 It is a control schematic diagram of a source-network coordinated primary frequency modulation optimization method according to an embodiment of the present application; Figure 5 It is a simulation result diagram of closed-loop optimization of frequency modulation indicators based on the source-network collaborative primary frequency modulation optimization method according to an embodiment of the present application; Figure 6 It is a block diagram of a source-network coordinated primary frequency modulation optimization system based on load demand according to an embodiment of the present application; Figure 7 It is a structural block diagram of an electronic device according to an embodiment of the present application. DETAILED DESCRIPTION

[0019] The embodiments of the present application are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0020] It should be noted that, unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific implementations and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0021] See also Figures 1 to 5 This embodiment provides a method for optimizing primary frequency modulation based on source-network collaboration based on load demand, including: Step S100: Acquire key parameter information of the power grid and the unit, wherein the key parameter information includes power grid frequency data, power grid power, generator unit output power and frequency modulation instructions; In this step, the grid frequency data, grid power, generator set output power and frequency modulation instruction data can be collected based on the corresponding hardware. For example, a high-precision frequency transmitter is used to collect grid frequency data; a power transmitter is used to collect grid power and generator set output power; and a power dispatching system interface is used to collect frequency modulation instructions and key indicators in the frequency modulation process to provide basic data support for subsequent frequency modulation performance analysis and optimization.

[0022] It should be noted that the traditional power system design mainly relies on the inertia and rotational mass of fossil fuel generators (such as coal-fired power and natural gas units) to provide frequency regulation support, but with the increasing proportion of renewable energy such as wind power and solar power, the traditional inertial response capability is limited. Renewable energy usually relies on power electronic devices (such as inverters) to access the grid. These devices do not have the same rotational inertia as synchronous generators, so they cannot directly contribute to frequency regulation capabilities like traditional generators. At the same time, with the opening of the power market, the operation of the power grid has become more complicated, and the risks of frequency fluctuations and power supply instability are increasing. The output of wind power and photovoltaic power generation has obvious volatility. Affected by meteorological conditions, changes in wind speed and light directly lead to fluctuations in power generation. This volatility has aggravated the fluctuation of grid frequency to a certain extent, making grid frequency regulation more difficult. The load demand in the power grid is also dynamically changing, especially in areas with large industrial loads, where the load fluctuations are large, which puts higher requirements on grid frequency regulation.

[0023] The primary frequency modulation control scheme in the related technology mainly relies on the adjustment relationship between the speed signal and the electrical frequency signal of the unit, but this scheme has exposed a series of limitations in modern power grids. First, the traditional frequency modulation control scheme usually has the problem of delayed frequency modulation response, that is, when the frequency changes, the unit cannot respond immediately, thus affecting the rapid stability of the power grid frequency. Secondly, in the case of small frequency difference, the adjustment effect of the traditional frequency modulation method is not obvious, especially when the power grid frequency fluctuates slightly or changes slowly, the unit's response is insufficient, resulting in the inability to effectively maintain frequency stability. Furthermore, in the traditional frequency modulation process, the unit adjustment sometimes has a reverse adjustment phenomenon, that is, under certain conditions, the frequency modulation response aggravates the frequency fluctuation, which is mainly due to the lag of the system dynamic characteristics and the unit control strategy. Finally, the compliance rate of the frequency modulation index is low, especially when the load fluctuation is large or the proportion of renewable energy is high, the traditional frequency modulation control method is often difficult to meet the accuracy requirements of the power grid frequency modulation, resulting in unstable power grid frequency and even the risk of power outage.

[0024] Traditional frequency regulation methods mainly rely on the regulation capability of the power generation end. However, with the increase in the proportion of renewable energy, the insufficient regulation capability of the power generation end has become a bottleneck restricting the stability of the power grid frequency. One of the key technologies of source-grid coordinated frequency regulation is how to achieve coordination and optimization between the power generation end and the load end. The power generation end participates in frequency regulation through power electronic devices and energy storage systems, while the load end regulates the load through intelligent control and demand response technology.

[0025] In order to achieve source-grid coordinated frequency regulation, it is necessary to develop an optimization method that can take into account the regulation capabilities of both the power generation and load ends. In this process, frequency regulation accuracy, response speed, and stability are the key technical problems that need to be solved. In view of the characteristics of frequency fluctuations in the power grid, how to design an efficient control strategy and avoid over-regulation and frequency regulation lag in practical applications. Therefore, this implementation provides a new source-grid coordinated primary frequency regulation optimization method, which should be able to simultaneously adjust the frequency response capabilities of the power generation and load ends, accurately adjust the frequency regulation amplitude of the unit, avoid over-regulation or reverse regulation, and improve the speed and accuracy of the frequency regulation response. Step S200: determining the index parameter information for evaluating the frequency regulation performance of the unit according to the key parameter information, wherein the index parameter information at least includes response lag time, integrated power and regulation reverse; In this step, after collecting the key parameter information, the response lag time is determined according to the grid frequency data and the frequency modulation instruction, wherein the response lag time is used to characterize the delay between the time point when the output power of the generator set starts to respond to the frequency modulation instruction and the time point when the frequency modulation instruction is issued, and the integrated power is determined according to the grid power and the output power of the generator set, and the regulation direction is determined according to the frequency modulation instruction and the direction of power increase or decrease.

[0026] In some embodiments, the grid t Frequency difference of time The calculation formula is as follows: in, For in time t The actual frequency measured at the moment, is the rated frequency of the power grid, the rated frequency is 50Hz; Response delay time The calculation formula is as follows: in, It is the moment when the output power of the generator set begins to change significantly. is the time when the frequency modulation instruction is issued, and the response lag time is determined by calculating the delay between the time when the output power of the generator set starts to respond to the frequency modulation instruction and the time when the frequency modulation instruction is issued; Points Power The calculation formula is as follows: in, is the real-time power, It is the initial power locked when the frequency modulation action passes through the dead zone. The integral start time is the frequency passing the dead zone time. K is the product coefficient; The reverse direction of regulation is determined by judging whether the direction of power increase or decrease is opposite to the frequency modulation instruction. The calculation formula is: in, and They are the increments of the frequency modulation command and the actual power change, respectively. If the change directions of the two are opposite, the reverse direction is 1, otherwise it is 0; Step S300: judging the index parameter information and quantifying the index parameter information based on a coding analysis method to determine the weak index parameters of the unit during the frequency modulation process; In this step, in order to realize the automatic processing of various parameters of the indicator parameter information, each indicator is first judged by the preset qualification standard. For example, the power contribution rate refers to the ratio of the integral power of the actual frequency modulation action to the theoretical action integral power. The power contribution rate is not less than 75% and is considered to meet the standard: In the formula, the actual integrated power , theoretical value of integrated charge ; A response lag time of no more than 3 seconds is considered to meet the standard. For the reverse regulation indicator, that is, when the integrated power is a negative value, the regulation is reversed and the indicator does not meet the standard.

[0027] In some embodiments, in order to realize automatic and precise processing of various parameters in electronic equipment, the response lag time, integrated power and regulation reverse are encoded, wherein the encoded index parameter information is used to determine the coding value corresponding to the frequency modulation result based on the binary method, and the coding values ​​of the response lag time, integrated power and regulation reverse are correlated to determine the numerical parameters used for quantification; based on the numerical parameters, the pass rate of each assessment indicator after correlation is statistically analyzed and the relationship between the assessment indicators is analyzed to determine the frequency modulation status information of the weak links in the frequency modulation process of the unit.

[0028] Optionally, the response lag time, the integral power and the coding values ​​of the reverse regulation are associated to determine the numerical parameters for quantification, including: the response lag time, the integral power and the coding values ​​of the reverse regulation are associated in binary, wherein, since the power contribution index must not meet the standard when the frequency modulation is reversed, the numerical coding results have 5 categories, namely [0, 1, 3, 5, 7], a value of 0 represents that all three indicators are qualified, a value of 1 represents that the integral power does not meet the standard, a value of 3 represents that the integral contribution rate is qualified but the response lag time indicator is unqualified, a value of 5 represents that the frequency modulation action is reversed and the response lag time indicator is qualified, and a value of 7 represents that all three indicators are unqualified, and the numerical parameters for quantification are determined, as shown in Table (1). For example, taking the unit's monthly frequency regulation assessment results as the data source, the pass rate of each assessment indicator is statistically analyzed and the relationship between the assessment indicators is analyzed on this basis. The unqualified percentages of the three major assessment indicators and their combinations are statistically analyzed, and the indicator with the largest percentage of unqualified percentage is analyzed. The unqualified percentage of integral electricity contribution rate is the largest, reaching 75% of the unqualified times.

[0029] Step S400: According to the weakness indicator parameter, the integral power closed-loop optimization module on the CCS system side determines the deviation value between the actual integral power and the theoretical integral power, and adds the deviation value to the frequency regulation compensation amount of the unit to perform closed-loop adjustment on the output power of the unit; In this step, the weak indicator parameter refers to the situation where the integral power is unqualified. At the same time, in actual applications, it is also found that the situation where the integral power contribution rate is unqualified is more prominent, especially in the frequency modulation process, the unit fails to fully adjust according to the theoretical power. Therefore, for the frequency modulation optimization plan for unqualified integral power, you can refer to Figure 3 and Figure 4 , add an integral power closed-loop optimization module on the CCS system side. This module calculates the actual value of the integral power in the frequency modulation process in real time, compares it with the theoretical value, calculates the deviation, and implements closed-loop control through the PI controller. The integral power deviation is added to the frequency modulation compensation of the unit. In this way, the deviation between the actual power and the theoretical power in the frequency modulation process will gradually decrease, making the frequency modulation process more accurate and improving the frequency modulation capability of the unit; For example, the integrated power closed-loop optimization module is integrated in the CCS system side, which calculates the integrated power of the whole frequency modulation process in real time and converts the actual value of the integrated power into the actual value of the integrated power. Theoretical value of integrated power The deviation is added to the unit frequency regulation compensation to form a closed-loop control; Specifically, on the CCS system side of the existing traditional frequency regulation scheme, the real-time frequency is calculated by the frequency difference function and the rated frequency to obtain the frequency feedback signal, and the frequency feedback signal is used as the unit frequency regulation compensation. The control signal is transmitted to the subsequent regulation module to generate a frequency regulation instruction to ensure that the unit output meets the load requirements; The integrated power closed-loop optimization module calculates the real-time deviation between the actual value of the integrated power and the theoretical value, and introduces a PI controller to implement closed-loop control. The PI controller output signal and the frequency feedback signal are superimposed on the unit frequency regulation compensation, so that the actual power gradually approaches the theoretical power. The actual value calculation formula of integrated power is as follows: in, is the real-time power, It is the initial power locked when the frequency modulation action passes through the dead zone. The integral start time is the frequency passing the dead zone time. K is the product coefficient, and the calculation formula for the theoretical value of integrated power is as follows: in, In the formula, is the difference between the actual frequency and the rated frequency, is the rated power of the unit, and K is the multiplication coefficient.

[0030] In order to ensure that the power contribution output by the generator set meets the standards of the power grid, the integral power closed-loop optimization module will compare the deviation between the actual integral power and the theoretical integral power in real time. The calculation formula is as follows: It should be noted that when the deviation between the actual integrated power and the theoretical integrated power When it is negative, it means that the current unit output power is lower than the theoretical value, and the system needs to increase the unit's frequency modulation power. When it is positive, it means that the power output of the unit is higher than the theoretical value, and the system needs to reduce the frequency modulation power. The module will The PI controller is introduced to obtain the output signal, and the output signal and the frequency feedback signal are superimposed on the frequency regulation compensation of the unit. The output power of the unit is continuously adjusted through closed-loop control so that the actual integrated power is consistent with the theoretical integrated power, thereby meeting the frequency regulation requirements of the power grid; Of course, if the weak indicator parameter is the response lag time, when the response lag time is too long, the optimization solution can be: replace the original mechanical hydraulic control valve with a high-frequency response electro-hydraulic servo valve (such as the MOOG valve). This servo valve can significantly shorten the full stroke action time of the valve, and its response frequency must reach more than 100Hz to support rapid adjustment. The MOOG electro-hydraulic servo valve can quickly respond to frequency modulation requirements and complete the displacement, speed and acceleration control of the actuator by converting low-power electrical signals into high-power hydraulic energy output; The sampling period of the control system is shortened from 1 second to 10ms, and a high-precision optical fiber frequency measurement device is used to capture frequency changes in real time. A quick pressure relief valve is installed at the inlet of the high-pressure cylinder of the turbine, and the heat storage capacity of the boiler is used to quickly release the stored energy at the beginning of the frequency deviation to provide instantaneous power support. This method can effectively alleviate the power shortage problem caused by response lag, especially under the frequency modulation requirements of small frequency difference and short duration, and can respond quickly and provide the necessary power support.

[0031] Similarly, if the weak indicator parameter is the frequency regulation reversal, it can be optimized and adjusted based on existing technologies. For example, by combining the unit characteristics with the frequency regulation mechanism, closed-loop management optimization can be carried out from system diagnosis to optimization implementation. Specific reference can be made to existing technologies for reasonable design based on actual needs.

[0032] Step S500: obtaining a frequency difference peak value and a frequency modulation duration in a closed-loop adjustment process, and determining whether the frequency difference peak value is less than a preset frequency difference threshold and whether the frequency modulation duration is greater than a preset duration threshold; In this step, although the deviation of the integrated power in the previous step has been effectively improved, the time series analysis of the frequency difference and power output data shows that there are still problems of insufficient response to small frequency differences and insufficient response in the later stage after long-term frequency modulation during the frequency modulation process; At present, the frequency of small frequency difference fluctuations in the grid frequency is much higher than that of large frequency difference, that is, the maximum frequency difference in most effective primary frequency regulation tests is less than 0.06Hz. For frequency regulation requirements with small frequency difference amplitude and short duration, the comprehensive valve position of the steam turbine changes very little under the conventional control scheme, and the load change is even covered by the power fluctuation of the unit itself, resulting in unqualified frequency regulation indicators or even reverse regulation.

[0033] To solve these problems, a frequency modulation index compensation module solution is proposed in this step. The solution includes small frequency difference response compensation and late response compensation after long-term frequency modulation. Small frequency difference response compensation: When the frequency difference peak is lower than the predetermined threshold, the compensation mechanism is started. The compensation module automatically adjusts the frequency modulation amplitude of the unit according to the absolute value of the current frequency difference and the frequency modulation duration, ensuring that the unit can still generate sufficient power adjustment under the condition of small frequency difference; Step S600: If yes, compensate for the small frequency difference response and the late response after frequency modulation based on the frequency modulation compensation module.

[0034] In this step, the goal of small frequency difference response compensation is to enhance the response of the unit when the grid frequency difference is small, so as to ensure that the unit can still provide sufficient power adjustment when the frequency difference is lower than the predetermined threshold. Usually, the insufficient response under small frequency difference is because the frequency regulation system will not make large adjustments under slight frequency difference by default. By increasing the compensation amount, the frequency regulation sensitivity under small frequency difference can be significantly improved. When the frequency difference The absolute value of When the small frequency difference response compensation is triggered, the calculation formula of the compensation increment is as follows: in, To compensate for the power increase, is the small frequency difference compensation gain coefficient, It is the difference between the actual frequency and the rated frequency; Compensation for late response after long-term frequency modulation: By introducing a compensation mechanism, the response capability of the unit after long-term frequency modulation is increased, the continuous frequency modulation capability is ensured, and the stability and reliability of the unit are improved; The late response compensation is mainly based on the frequency modulation duration and the change of frequency difference. After the frequency modulation process lasts for a period of time, the compensation power is appropriately increased to restore the unit response capability to a higher level. Assume that the FM duration is , when the time exceeds the threshold When the late response compensation is enabled, the compensation increment is calculated according to the following formula: in, To compensate for the power increment later, is the post-compensation gain coefficient, is the frequency modulation duration, The duration of the frequency modulation exceeds the preset frequency difference threshold.

[0035] For example, Figure 2 For the existing traditional frequency modulation scheme, an integral power closed-loop optimization module and a frequency modulation compensation module are added to the CCS system side of the traditional scheme (such as Figure 3 As shown in the figure, the integral power closed-loop optimization module calculates the integral power compensation; the frequency compensation module includes the small frequency difference response compensation and the late response compensation; then the frequency compensation module is added to the DEH system side to obtain the source network collaborative primary frequency optimization solution (as shown in the figure). Figure 4 as shown).

[0036] In some examples, in order to verify the feasibility of the method steps of the above embodiment, the effect of the designed primary frequency regulation optimization scheme is verified by using a step constant disturbance. The initial load of the unit is 180.7MW, the disturbance frequency is 0.095Hz, the duration is 70s, and the speed inequality of the speed regulation system is 4%. The traditional scheme and the designed primary frequency regulation optimization scheme are used for primary frequency regulation response. The simulation results are as follows: Figure 5 shown.

[0037] from Figure 5 It can be seen that there is a large difference between the actual load of the unit and the ideal curve at the beginning of the frequency regulation action. At this time, the closed-loop optimization module of the frequency regulation index enhances the power control parameters. As the frequency regulation process continues, the actual load gradually approaches the ideal curve, and the difference gradually decreases. By comparison, it can be found that after the control parameters are adaptively adjusted using the primary frequency regulation optimization scheme, the rapidity of the frequency regulation response has been effectively improved.

[0038] It should be noted that in the above method steps, the grid frequency data, grid power, generator set output power and frequency regulation instruction information are collected at the power generation end respectively, and the response lag time, integral power and regulation reverse index for evaluating the frequency regulation performance of the unit are calculated respectively. The three major indexes are quantified by the binary coding analysis method. The electronic equipment can realize automatic statistics of the occurrence frequency of different coding values ​​and the correlation analysis of the index coding, and identify the integral power index affecting the frequency regulation performance of the unit. By adding the integral power closed-loop optimization module at the load end, the real-time calculation and adjustment of the unit frequency regulation compensation amount are realized, so that the deviation between the actual power and the theoretical power is gradually reduced, and The frequency regulation index compensation increment is composed of small frequency difference response compensation and late response compensation. The frequency regulation index compensation increment is added on the CCS system side and accumulated with the original unit frequency regulation compensation. At the same time, the compensation increment is superimposed on the frequency feedback signal on the DEH system side to improve the frequency regulation amplitude under small frequency difference and the response strength after long-term frequency regulation, and enhance the comprehensive performance of unit frequency regulation. Through this compensation mechanism, the frequency regulation index compensation module ensures that the generator set can operate effectively in small frequency difference and long-term frequency regulation response scenarios, avoids insufficient frequency regulation caused by small frequency difference, and improves the frequency regulation response speed and performance of the unit, especially when the grid frequency changes smoothly but needs to be continuously adjusted, thereby avoiding over-regulation or reverse regulation, while improving the speed and accuracy of frequency regulation response, and effectively improving the frequency stability of the grid.

[0039] See also Figure 6 , Figure 6 The block diagram of the source network coordinated primary frequency regulation optimization system based on load demand provided by this embodiment is shown. The source network coordinated primary frequency regulation optimization system based on load demand 200 includes: The acquisition module 210 is configured to acquire key parameter information of the power grid and the unit, wherein the key parameter information includes power grid frequency data, power grid power, generator unit output power and frequency regulation instructions; The indicator parameter confirmation module 220 is configured to determine the indicator parameter information for evaluating the frequency regulation performance of the unit according to the key parameter information, wherein the indicator parameter information at least includes response lag time, integral power and regulation reverse direction; The quantization coding module 230 is configured to determine the index parameter information and quantize the index parameter information based on a coding analysis method to determine the weak index parameter of the unit during the frequency modulation process; The integrated power optimization module 240 is configured to determine the deviation value between the actual and theoretical integrated power of the integrated power based on the integrated power closed-loop optimization module on the CCS system side according to the weak indicator parameter, and add the deviation value to the frequency regulation compensation amount of the unit to perform closed-loop adjustment on the output power of the unit; The judgment module 250 is configured to obtain a frequency difference peak value and a frequency modulation duration in the closed-loop adjustment process, and judge whether the frequency difference peak value is less than a preset frequency difference threshold and whether the frequency modulation duration is greater than a preset duration threshold; The frequency modulation compensation module 260 is configured to compensate for the small frequency difference response and the late response after frequency modulation based on the frequency modulation compensation module according to the judgment result of the judgment module.

[0040] It can be understood that, in the load demand-based source-network coordinated primary frequency modulation optimization system 200 in this embodiment, each module runs the above Figure 1 The steps of a source-network coordinated primary frequency modulation optimization method based on load demand in the corresponding embodiment, and the technical effects that can be achieved can be referred to the above Figure 1 The description of the technical effects achieved in the corresponding embodiments will not be repeated here.

[0041] See also Figure 7 , Figure 7 5 is a structural block diagram of an electronic device provided in an embodiment of the present application, wherein a server 500 of the electronic device includes: a processor 501, a memory 502, and a computer program 503 stored in the memory 502 and executable on the processor 501, such as a program of a method for optimizing primary frequency modulation based on source network collaboration in load demand. When the processor 501 executes the computer program 503, the steps of the method for optimizing primary frequency modulation based on source network collaboration in load demand in the above-mentioned embodiments are implemented, such as Figure 1 The corresponding embodiment of the step S100 to step S600. Alternatively, the processor 501 executes the computer program 503 to implement the above Figure 6 The functions of each module in the corresponding embodiment are, for example, Figure 6For details on the functions of the modules (eg, acquisition module 210), please refer to Figure 6 The relevant descriptions in the corresponding embodiments are not repeated here.

[0042] Exemplarily, the computer program 503 may be divided into one or more units, one or more units are stored in the memory 502, and are executed by the processor 501 to complete the technical solution provided in the above embodiment. One or more units may be a series of computer program instruction segments that can complete specific functions, and the instruction segments are used to describe the execution process of the computer program 503 in the server 500.

[0043] The electronic device may include, but is not limited to, a processor 501 and a memory 502. Those skilled in the art will appreciate that Figure 7 It is only an example of the server 500 in the electronic device and does not constitute a limitation of the server 500. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the turntable terminal device may also include an input and output terminal device, a network access terminal device, a bus, etc.

[0044] The processor 501 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0045] The memory 502 may be an internal storage unit of the server 500, such as a hard disk or memory of the server 500. The memory 502 may also be an external storage terminal device of the server 500, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the server 500. Further, the memory 502 may also include both an internal storage unit of the server 500 and an external storage terminal device. The memory 502 is used to store computer programs and other programs and data required by the turntable terminal device. The memory 502 may also be used to temporarily store data that has been output or is to be output.

[0046] In some embodiments, a computer-readable storage medium is also provided, which stores a computer program. When the computer program is executed by a processor, it implements the steps of the source network collaborative primary frequency regulation optimization method based on load demand as described in the above embodiment.

[0047] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0048] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Among them, the computer-readable storage medium can be non-volatile or volatile. Based on this understanding, the present application implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable storage medium may include: any entity or device capable of carrying computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electrical carrier signal, telecommunication signal and software distribution medium, etc.

[0049] The terms "first", "second", "third", etc. in the specification and claims of the present application and the drawings are used to distinguish different objects rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a series of steps or units are included, or optionally, steps or units not listed are included, or optionally, other steps or units inherent to these processes, methods, products or devices are included.

[0050] Only the part relevant to the present application is shown in the accompanying drawings, but not all of the content. Before discussing the exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processing or methods depicted as flow charts. Although the flow chart describes each operation (or step) as a sequential process, many of the operations therein can be implemented in parallel, concurrently or simultaneously. In addition, the order of each operation can be rearranged. When its operation is completed, the process can be terminated, but it can also have additional steps not included in the accompanying drawings. The process can correspond to a method, function, procedure, subroutine, subprogram, etc.

[0051] The terms "component", "module", "system", "unit", etc. used in this specification are used to represent computer-related entities, hardware, firmware, a combination of hardware and software, software, or software in execution. For example, a unit can be, but is not limited to, a process running on a processor, a processor, an object, an executable file, an execution thread, a program, and / or distributed between two or more computers. In addition, these units can be executed from various computer-readable media having various data structures stored thereon. Units can communicate through local and / or remote processes, for example, based on signals having one or more data packets (e.g., data from a second unit interacting with another unit in a local system, a distributed system, and / or a network. For example, the Internet interacts with other systems via signals).

[0052] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0053] Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Mentioning "embodiment" in this article means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present embodiment application. The appearance of this phrase in various positions in the specification is not necessarily the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It can be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0054] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

[0055] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the disclosure disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

Claims

1. A method for optimizing primary frequency modulation based on source-network coordination based on load demand, characterized in that: include: Obtaining key parameter information of the power grid and the unit, the key parameter information including power grid frequency data, power grid power, generator unit output power and frequency modulation instructions; Determine, based on the key parameter information, index parameter information for evaluating the frequency regulation performance of the unit, wherein the index parameter information at least includes response lag time, integral power, and regulation reverse direction; Determining the index parameter information and quantifying the index parameter information based on a coding analysis method to determine weak index parameters of the unit during the frequency modulation process; According to the weakness indicator parameter, the integral power closed-loop optimization module on the CCS system side determines the deviation value between the actual integral power and the theoretical integral power, and adds the deviation value to the frequency regulation compensation amount of the unit to perform closed-loop adjustment on the output power of the unit; Obtaining a frequency difference peak value and a frequency modulation duration in a closed-loop adjustment process, and determining whether the frequency difference peak value is less than a preset frequency difference threshold and whether the frequency modulation duration is greater than a preset duration threshold; If so, the small frequency difference response and the late response after frequency modulation are compensated based on the frequency modulation compensation module.

2. The method for optimizing primary frequency modulation based on source-network coordination based on load demand according to claim 1, characterized in that: Determining the index parameter information for evaluating the frequency regulation performance of the unit according to the key parameter information, wherein the index parameter information at least includes response lag time, integral power, and regulation reverse, including: Determine a response lag time according to the grid frequency data and the frequency modulation instruction, wherein the response lag time is used to characterize the delay between the time point when the output power of the generator set starts to respond to the frequency modulation instruction and the time point when the frequency modulation instruction is issued; Determine the integrated power according to the grid power and the output power of the generator set, and The reverse direction of the regulation is determined according to the frequency modulation instruction and the direction of power increase or decrease.

3. The method for optimizing primary frequency modulation based on source-network coordination based on load demand according to claim 1, characterized in that: Determining the integrated electric quantity according to the power grid and the output power of the generator set, and determining the reverse direction of the regulation according to the frequency regulation instruction and the direction of power increase or decrease, including: Points Power The calculation expression is: ， in, is the real-time power, It is the initial power locked when the frequency modulation action passes through the dead zone. The integral start time is the frequency passing through the dead zone time. K is the product coefficient; The calculation expression for adjusting the reverse direction is: ， in, and They are the increments of the frequency modulation command and actual power change respectively. If the directions of their changes are opposite, the reverse direction is 1, otherwise it is 0.

4. The method for optimizing primary frequency modulation based on source-network coordination based on load demand according to claim 1, characterized in that: The step of determining the index parameter information and quantifying the index parameter information based on a coding analysis method to determine the weak index parameters of the unit during the frequency modulation process includes: The response lag time, the integrated power, and the reverse direction of regulation are encoded, wherein the compliance code of each indicator in the indicator parameter information is 0, and the non-compliance code is 1, the integrated power is less than 50 and is not up to standard, the response lag time is greater than 2 and is not up to standard, and the reverse direction of regulation indicator is not up to standard when the integrated power is a negative value; Determine the encoding value corresponding to the frequency modulation result based on the binary method for the encoded indicator parameter information; Correlating the response lag time, the integrated electrical quantity and the coded value of the regulation reversal to determine a numerical parameter for quantification; Based on the numerical parameters, the pass rate of each assessment indicator after correlation is statistically analyzed and the relationship between the assessment indicators is analyzed to determine the frequency regulation status information of the weak links in the frequency regulation process of the unit.

5. The method for optimizing primary frequency modulation based on source-network coordination based on load demand according to claim 4 is characterized in that: The step of correlating the response lag time, the integrated power, and the coded value of the reverse adjustment to determine a numerical parameter for quantization includes: The response lag time, the integrated power and the reverse regulation coding values ​​are binary-correlated, wherein there are five categories of numerical coding results, namely [0, 1, 3, 5, 7]. A value of 0 represents that all three indicators are qualified, a value of 1 represents that the integrated power does not meet the standard, a value of 3 represents that the integrated contribution rate is qualified but the response lag time indicator is unqualified, a value of 5 represents that the frequency regulation action is reversed but the response lag time indicator is qualified, and a value of 7 represents that all three indicators are unqualified, thereby determining the numerical parameters used for quantification.

6. The method for optimizing primary frequency modulation based on source-network coordination based on load demand according to claim 1, characterized in that: The method of determining the deviation between the actual and theoretical integrated power quantities of the integrated power quantities based on the integrated power quantity closed-loop optimization module on the CCS system side according to the weak indicator parameter, and adding the deviation value to the frequency regulation compensation amount of the unit to perform closed-loop adjustment on the output power of the unit, includes: The integral electric quantity theoretical value calculation expression is: ， in, , In the formula, is the difference between the actual frequency and the rated frequency, is the rated power of the unit, and K is the multiplication coefficient.

7. The method for optimizing primary frequency modulation based on source-network coordination based on load demand according to claim 1, characterized in that: If so, compensating for the small frequency difference response and the later response after frequency modulation based on the frequency modulation compensation module includes: The calculation expression of the small frequency difference response compensation power increment is: ， in, To compensate for the power increase, is the small frequency difference compensation gain coefficient, It is the difference between the actual frequency and the rated frequency; The calculation expression of the late response compensation power increment is: ， in, To compensate for the power increment later, is the post-compensation gain coefficient, is the frequency modulation duration, The duration of the frequency modulation exceeds the preset frequency difference threshold.

8. A source-network coordinated primary frequency modulation optimization system based on load demand, characterized in that: include: An acquisition module is configured to acquire key parameter information of the power grid and the unit, wherein the key parameter information includes power grid frequency data, power grid power, generator unit output power and frequency modulation instructions; An index parameter confirmation module is configured to determine index parameter information for evaluating the frequency regulation performance of the unit according to the key parameter information, wherein the index parameter information at least includes response lag time, integral power, and regulation reverse; A quantization coding module is configured to determine the index parameter information and quantize the index parameter information based on a coding analysis method to determine the weak index parameters of the unit during the frequency modulation process; The integral power optimization module is configured to determine the deviation value between the actual and theoretical integral power of the integral power based on the integral power closed-loop optimization module on the CCS system side according to the weak indicator parameter, and add the deviation value to the frequency regulation compensation amount of the unit to perform closed-loop adjustment on the output power of the unit; A judgment module is configured to obtain a frequency difference peak value and a frequency modulation duration in a closed-loop adjustment process, and judge whether the frequency difference peak value is less than a preset frequency difference threshold and whether the frequency modulation duration is greater than a preset duration threshold; The frequency modulation compensation module is configured to compensate for the small frequency difference response and the late response after frequency modulation based on the frequency modulation compensation module according to the judgment result of the judgment module.

9. An electronic device, characterized in that: include: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the steps of a source-network coordinated primary frequency regulation optimization method based on load demand as described in any one of claims 1-7.

10. A computer-readable storage medium having computer program instructions stored thereon, characterized in that: When the computer program instructions are executed by the processor, the steps of a source-network coordinated primary frequency regulation optimization method based on load demand as described in any one of claims 1-7 are implemented.

Images