Online emergency control quantity calculation method, device, storage medium and computing equipment

Abstract

The present invention discloses a method, device, storage medium and computing equipment for calculating an online emergency control quantity. The present invention generates the worst new energy short-term power fluctuation mode based on the current online mode, calculates the equivalent single-machine electromagnetic power mutation quantity considering the new energy short-term power fluctuation according to the equivalent single-machine trajectory of the worst new energy short-term power fluctuation mode, calculates the online emergency control quantity, realizes the rapid calculation of the emergency control quantity considering the new energy short-term power fluctuation, and improves the reliability and accuracy of the online transient safety and stability control strategy.

Description

Technical Field

[0001] The present invention relates to an online emergency control quantity calculation method, device, storage medium and computing equipment, and belongs to the field of power system automatic control. Background Art

[0002] As the operating modes and safety and stability characteristics of large power grids become increasingly complex and volatile, the reliability of online emergency control strategies has long been a key technology that needs to be addressed in large power grid safety and stability control. Existing online emergency control methods calculate online emergency control strategies based on the actual operating status of the power system. When an actual fault occurs, emergency control is quickly implemented according to the configured matching conditions, greatly improving the reliability of the emergency control strategy. However, with the increasing proportion of renewable energy installed capacity, the uncertainty of operating modes increases. If the fluctuation of renewable energy between the time of online strategy calculation and the occurrence of a fault is large, the system stability will deteriorate. Emergency control strategies generated based on current online methods may be subject to under-control risks. Conservative methods generated through sensitivity analysis or heuristic methods do not meet the timeliness requirements of online calculations. Therefore, it is necessary to study methods for the rapid calculation of online emergency control variables that take into account short-term power fluctuations of renewable energy. Summary of the Invention

[0003] The present invention provides an online emergency control quantity calculation method, device, storage medium and computing equipment, which solve the problems disclosed in the background technology.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] Online emergency control quantity calculation method, including:

[0006] Generate the worst short-term power fluctuation mode of renewable energy based on the current online mode of the system;

[0007] Under the worst short-term power fluctuation mode of renewable energy, obtain the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power as the power angle changes;

[0008] According to the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle, the equivalent single-machine electromagnetic power mutation considering the short-term power fluctuation of new energy is calculated;

[0009] The online emergency control quantity is calculated based on the equivalent single-machine electromagnetic power mutation quantity considering the short-term power fluctuation of new energy.

[0010] The worst short-term power fluctuations of renewable energy are:

[0011] Based on the current online mode of the system, the new energy of the critical group decreases, the reduced capacity of the new energy is A% of the new energy access capacity of the critical group, the output of the synchronous machine of the critical group increases by the output of the reduced new energy, and at the same time, the new energy of the remaining group increases, the increased capacity of the new energy is A% of the new energy access capacity of the remaining group, and the output of the synchronous machine of the remaining group decreases by the output of the increased new energy; where A is the threshold.

[0012] Under the worst short-term power fluctuation mode of renewable energy, obtain the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power as the power angle changes, including:

[0013] Under the worst short-term power fluctuation mode of new energy, the equivalent single-machine electromagnetic power remains unchanged, and the equivalent single-machine mechanical power increases by The trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power as the power angle changes is ΔP m The difference between the electromagnetic power of the equivalent single machine and the electromagnetic power of the equivalent single machine; S is the critical group inertia of the system when emergency control is not implemented, M A is the remaining group inertia of the system when emergency control is not implemented, ΔP ms is the increase in output of the critical group synchronous machine, ΔP ma The output reduction of the remaining group of synchronous machines.

[0014] Based on the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle, the equivalent single-machine electromagnetic power mutation considering the short-term power fluctuation of new energy is calculated, including:

[0015] According to the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle, a model of increasing the deceleration area when the system is critically stable after the implementation of emergency control is constructed;

[0016] Based on the model of increasing deceleration area, the dynamic saddle point power angle of the system at critical stability after emergency control is implemented under the worst short-term power fluctuation of new energy is calculated;

[0017] According to the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst short-term power fluctuation of renewable energy, the equivalent single-machine electromagnetic power mutation considering the short-term power fluctuation of renewable energy is calculated.

[0018] The model for increasing the deceleration area is:

[0019]

[0020] Among them, A3′ is the deceleration area increased when the system is critically stable after the emergency control is implemented, ΔP m is the equivalent single-machine electromechanical power increase under the worst short-term power fluctuation of new energy, δ kThe trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle and ΔP when the emergency control is not implemented in the current online mode m The angle corresponding to the intersection point, δ is the power angle variable, a, b, c are parameters, ΔP′ is the equivalent single-machine electromagnetic power mutation considering the short-term power fluctuation of new energy, δ c ' g To implement emergency control of rotor angle under the worst short-term power fluctuation of renewable energy, It is the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst short-term power fluctuation of renewable energy.

[0021] The formula for calculating the equivalent single-machine electromagnetic power mutation considering the short-term power fluctuation of new energy is:

[0022]

[0023] Among them, ΔP′ is the equivalent single-machine electromagnetic power mutation considering the short-term power fluctuation of new energy, ΔP m is the equivalent single-machine electromechanical power increase under the worst short-term power fluctuation of new energy, a, b, c are parameters, It is the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst short-term power fluctuation of renewable energy.

[0024] The formula for calculating the online emergency control quantity is:

[0025]

[0026] Among them, M S is the critical group inertia of the system when emergency control is not implemented, M A is the remaining group inertia of the system when emergency control is not implemented, ΔP′ is the equivalent single-machine electromagnetic power mutation considering the short-term power fluctuation of new energy, ΔP e ' is the online emergency control quantity, M' g After emergency control is implemented, the inertia of the disconnected unit is M' g .

[0027] Online emergency control quantity calculation system, including:

[0028] The worst-case mode generation module generates the worst-case short-term power fluctuation mode of renewable energy based on the current online mode of the system;

[0029] The trajectory acquisition module obtains the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power as the power angle changes under the worst short-term power fluctuation of new energy;

[0030] The mutation calculation module calculates the equivalent single-machine electromagnetic power mutation taking into account the short-term power fluctuations of new energy sources based on the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle;

[0031] The control quantity calculation module calculates the online emergency control quantity based on the equivalent single-machine electromagnetic power mutation quantity taking into account the short-term power fluctuation of new energy.

[0032] The worst short-term power fluctuation mode of renewable energy in the worst mode generation module is:

[0033] Based on the current online mode of the system, the new energy of the critical group decreases, the reduced capacity of the new energy is A% of the new energy access capacity of the critical group, the output of the synchronous machine of the critical group increases by the output of the reduced new energy, and at the same time, the new energy of the remaining group increases, the increased capacity of the new energy is A% of the new energy access capacity of the remaining group, and the output of the synchronous machine of the remaining group decreases by the output of the increased new energy; where A is the threshold.

[0034] The mutation amount calculation module constructs an increased deceleration area model when the system is critically stable after emergency control is implemented based on the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle. Based on the increased deceleration area model, the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst new energy short-term power fluctuation mode is calculated. Based on the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst new energy short-term power fluctuation mode, the equivalent single-machine electromagnetic power mutation amount considering the new energy short-term power fluctuation is calculated.

[0035] A computer-readable storage medium storing one or more programs, wherein the one or more programs include instructions that, when executed by a computing device, cause the computing device to perform an online emergency control quantity calculation method.

[0036] A computing device includes one or more processors, one or more memories, and one or more programs, wherein the one or more programs are stored in the one or more memories and configured to be executed by the one or more processors, and the one or more programs include instructions for executing an online emergency control quantity calculation method.

[0037] The beneficial effects achieved by the present invention are as follows: the present invention generates the worst new energy short-term power fluctuation mode based on the current online mode, calculates the equivalent single-machine electromagnetic power mutation amount considering the new energy short-term power fluctuation according to the equivalent single-machine trajectory of the worst new energy short-term power fluctuation mode, calculates the online emergency control amount, realizes the rapid calculation of the emergency control amount considering the new energy short-term power fluctuation, and improves the reliability and accuracy of the online transient safety and stability control strategy. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1is a flow chart of the method of the present invention;

[0039] Figure 2 This is a schematic diagram of a simple system with 6 machines;

[0040] Figure 3 is the equivalent single-machine system generator curve. DETAILED DESCRIPTION

[0041] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0042] like Figure 1 As shown, the online emergency control quantity calculation method includes the following steps:

[0043] Step 1: Generate the worst short-term power fluctuation mode of renewable energy based on the current online mode of the system;

[0044] Step 2: Under the worst short-term power fluctuation mode of renewable energy, obtain the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power as the power angle changes;

[0045] Step 3: Calculate the equivalent single-machine electromagnetic power mutation amount considering the short-term power fluctuation of new energy based on the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle;

[0046] Step 4: Calculate the online emergency control quantity based on the equivalent single-machine electromagnetic power mutation quantity considering the short-term power fluctuation of new energy.

[0047] The above method is applied to Hamiltonian systems or non-Hamiltonian systems with small time-varying effects. The worst short-term power fluctuation mode of renewable energy is generated based on the current online method. According to the equivalent single-machine trajectory of the worst short-term power fluctuation mode of renewable energy, the equivalent single-machine electromagnetic power mutation amount considering the short-term power fluctuation of renewable energy is calculated, and the online emergency control amount is calculated. This realizes the rapid calculation of the emergency control amount considering the short-term power fluctuation of renewable energy, and improves the reliability and accuracy of the online transient safety and stability control strategy.

[0048] Taking a single anticipated fault as an example, parallel processing is used to implement multiple anticipated faults. In the current online mode, based on the EEAC theory, the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power as the power angle changes can be obtained. If the system is transiently unstable, it is necessary to sample the above method to calculate the online emergency control quantity. If the system is stable, the emergency control quantity is 0.

[0049] When emergency control is not implemented in the current online mode, the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle can be equivalent to a quadratic equation with respect to the power angle, which can be expressed as follows:

[0050] P e -P m =aδ 2 +bδ+c (1)

[0051] Among them, P e is the equivalent single-machine electromagnetic power when the emergency control is not implemented in the current online mode, P m is the equivalent single-machine mechanical power when emergency control is not implemented in the current online mode, δ is the power angle variable, a, b, and c are parameters, and can be solved by curve fitting the data of the trajectory at the fault removal point and the dynamic saddle point.

[0052] Since it only applies to Hamiltonian systems or non-Hamiltonian systems with small time-varying effects, there is no P-axis effect. When the equivalent single-machine electromagnetic power mutation amount is ΔP after emergency control is implemented and the system is in critical stability, the function of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle can be:

[0053] P e * -P m * =aδ 2 +bδ+c+ΔP (2)

[0054] Among them, P e * is the equivalent single-machine electromagnetic power after emergency control is implemented in the current online mode, P m * It is the equivalent single-machine mechanical power after emergency control is implemented in the current online mode.

[0055] When the system is in critical stability after emergency control is implemented, the deceleration area A3 added by the system is equal to the transient kinetic energy of the dynamic saddle point. The solution A3 for the dynamic saddle point power angle and ΔP of the system can be obtained, which can be expressed as follows:

[0056]

[0057]

[0058] Among them, M S is the critical group inertia of the system when emergency control is not implemented, M A is the remaining group inertia of the system when emergency control is not implemented, ω DSP is the angular velocity of the system dynamic saddle point when emergency control is not implemented, δ cg is the rotor angle at the moment of emergency control in the current online mode, is the dynamic saddle point power angle when the system is critically stable after emergency control is implemented in the current online mode, δ DSP It is the dynamic saddle point power angle when emergency control is not implemented in the current online mode.

[0059] Combining formulas (3) and (4), we can get δ DSP and ΔP. When emergency control is implemented and the active output of the switched generator is fully provided by the generators in the critical group, the inertia of the switched unit is M g , the actual control quantity is:

[0060]

[0061] Where ΔP e The actual control quantity.

[0062] Based on the similar principles mentioned above, the emergency control quantity considering the short-term power fluctuation of renewable energy can be calculated as follows:

[0063] First, based on the current online mode of the system, the worst short-term power fluctuation mode of renewable energy is generated;

[0064] Using the current method to predict the oscillation center of the minimum transient stability margin clustering pattern under fault conditions as the cut set, the power grid is divided into two parts: the renewable energy generation equipment connected to the critical group generators is classified as the critical group, and the renewable energy generation equipment connected to the remaining group generators is classified as the remaining group. Since the renewable energy fluctuation period is considered to be 5-10 minutes, the output of the synchronous generators in the critical group increases and the output of the synchronous generators in the remaining group decreases during this period. Therefore, the units must remain in operation and only the active reserve of the synchronous generators must be changed.

[0065] Therefore, the worst short-term power fluctuation mode of renewable energy is as follows: Based on the current online mode of the system, the critical group renewable energy is reduced, the renewable energy reduction capacity is A% of the critical group renewable energy access capacity, and the critical group synchronous machine output increase ΔP ms The output of the new energy is reduced, while the remaining group of new energy increases. The increased capacity of new energy is A% of the remaining group of new energy access capacity. The output of the remaining group of synchronous machines is reduced by ΔP ma is the output of the increased new energy; where A is the threshold, which is generally 5.

[0066] Under the worst short-term power fluctuation mode of new energy, the equivalent single-machine electromagnetic power remains unchanged, and the equivalent single-machine mechanical power increases by The trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power as the power angle changes is ΔP m The difference between the electromagnetic power of the equivalent single machine and the electromagnetic power of the equivalent single machine; S is the critical group inertia of the system when emergency control is not implemented, M A is the remaining group inertia of the system when emergency control is not implemented, ΔP ms is the increase in output of the critical group synchronous machine, ΔP ma is the output reduction of the remaining synchronous machines. After the fault included in the trajectory disappears, the cut-off angle increases to in, is the angular velocity of the equivalent single-machine mapping system, ω0 is the initial value of the angular velocity of the equivalent single-machine mapping system, and its value is zero, δ τ is the initial resection angle.

[0067] According to the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle, the integral area of power and power angle, as well as ΔP m and (δ τ ′-δ τ ) is used to construct a model for the increased deceleration area when the system is critically stable after the implementation of emergency control. This model is mainly constructed from two perspectives, as follows:

[0068] Under the worst short-term power fluctuation mode of new energy, the system is critically stable after emergency control is implemented, and the increased deceleration area A3′ of the system can be expressed as:

[0069]

[0070] Where ΔP m is the equivalent single-machine electromechanical power increase under the worst short-term power fluctuation of new energy, δ k The trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle and ΔP when the emergency control is not implemented in the current online mode m The angle corresponding to the intersection point, δ τ is the fault clearing point power angle when emergency control is not implemented in the current online mode, δ DSP is the dynamic saddle point power angle when emergency control is not implemented in the current online mode, δ τ ′ is the power angle of the fault removal point after the fault disappears, (P e -P m ) τ It is the sudden change of the difference between the electromagnetic power and mechanical power of a single machine at the fault removal point when the emergency control is not implemented in the current online mode;

[0071] The system is a Hamiltonian system. Since there is no P-axis effect, the increased deceleration area A3′ of the system can be expressed as:

[0072]

[0073] Among them, A3′ is the deceleration area increased when the system is critically stable after the emergency control is implemented, ΔP′ is the equivalent single-machine electromagnetic power mutation after the emergency control is implemented under the worst new energy short-term power fluctuation mode, that is, the equivalent single-machine electromagnetic power mutation considering the new energy short-term power fluctuation, δ c ' g To implement emergency control of rotor angle under the worst short-term power fluctuation of renewable energy, It is the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst short-term power fluctuation of renewable energy.

[0074] According to the model of increasing the deceleration area, the dynamic saddle point power angle of the system when the system is critically stable after emergency control is implemented under the worst new energy short-term power fluctuation mode is calculated. That is, by combining (6) and (7), we can calculate according to Using formula (8), the equivalent single-machine electromagnetic power mutation considering the short-term power fluctuation of new energy can be calculated;

[0075]

[0076] Among them, ΔP′ is the equivalent single-machine electromagnetic power mutation considering the short-term power fluctuation of new energy.

[0077] When emergency control is implemented and the active output of the switched-off generator is all provided by the generators in the critical group, the inertia of the switched-off unit is M g ′, based on the equivalent single-machine electromagnetic power mutation considering the short-term power fluctuation of new energy, the online emergency control quantity can be calculated. The specific formula is as follows:

[0078]

[0079] Where ΔP e ′ is the online emergency control quantity.

[0080] by Figure 2 Taking the 6-machine simple system as an example, it is a new energy and synchronous machine transmission system, where the maximum capacity of the critical group new energy on that day is 400MW, and the remaining group new energy is 0. Under the current online mode, the new energy access is 300MW, the critical group generator is 200MW, and MS / MA=0.05. Figure 3 Table 1 shows the power, synchronous unit output, DSP point angle change, and emergency control quantity before and after the new energy fluctuation.

[0081] Table 1 Data table before and after new energy fluctuations

[0082]

[0083] The expected fault is a busbar 3-busbar 1 short circuit fault that disappears 0.14s later. After the fault, generators 21 to 25 become transiently unstable relative to generator 1, and the generator is disconnected 0.2s later. The fitting method shows that a = -1.77, b = 5.81, and c = -3.36 when emergency control is not implemented in the current online mode. When the critical group new energy fluctuates by 5%, that is, 20MW, After the implementation of emergency control, the dynamic saddle point of the system critical stability increases from 151.2° to 159°. Substituting it into formula (9), it can be obtained that the actual emergency control amount increases by 74.8MW. That is, considering the short-term fluctuation of renewable energy and the critical stability of the system after the fault, the emergency control amount is 134.8MW, which is 1.5% different from the actual simulation error.

[0084] The above method is based on the EEAC theory and combines the changes in the mechanical power of synchronous units under short-term fluctuations of renewable energy. It derives the equivalent single-unit dynamic saddle point when the system is critically stable after emergency control is adopted, realizes the rapid and accurate estimation of the online emergency shutdown amount under short-term fluctuations of renewable energy, and improves the adaptability of online emergency control in the scenario of short-term fluctuations of renewable energy.

[0085] It should be noted that the above method is only applicable when the two groups are relatively unstable after the expected fault and the influence of time-varying factors is not significant. In addition, during the fluctuation of renewable energy, the on / off state of the synchronous unit, that is, the inertia, should remain unchanged.

[0086] Based on the same technical solution, the present invention also discloses a software device of the above method, an online emergency control quantity calculation device, comprising:

[0087] The severe mode generation module generates the worst short-term power fluctuation mode of new energy based on the current online mode of the system.

[0088] The worst short-term power fluctuation mode of renewable energy in the worst mode generation module is:

[0089] Based on the current online mode of the system, the new energy of the critical group decreases, the reduced capacity of the new energy is A% of the new energy access capacity of the critical group, the output of the synchronous machine of the critical group increases by the output of the reduced new energy, and at the same time, the new energy of the remaining group increases, the increased capacity of the new energy is A% of the new energy access capacity of the remaining group, and the output of the synchronous machine of the remaining group decreases by the output of the increased new energy; where A is the threshold.

[0090] The trajectory acquisition module obtains the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power as the power angle changes under the worst short-term power fluctuation mode of new energy.

[0091] The mutation amount calculation module constructs an increased deceleration area model when the system is critically stable after emergency control is implemented based on the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle. Based on the increased deceleration area model, the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst new energy short-term power fluctuation mode is calculated. Based on the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst new energy short-term power fluctuation mode, the equivalent single-machine electromagnetic power mutation amount considering the new energy short-term power fluctuation is calculated.

[0092] The control quantity calculation module calculates the online emergency control quantity based on the equivalent single-machine electromagnetic power mutation quantity taking into account the short-term power fluctuation of new energy.

[0093] In the above device, the data processing flow and method of each module are consistent and will not be described again here.

[0094] Based on the same technical solution, the present invention also discloses a computer-readable storage medium storing one or more programs, wherein the one or more programs include instructions, which, when executed by a computing device, enable the computing device to perform an online emergency control quantity calculation method.

[0095] Based on the same technical solution, the present invention also discloses a computing device, including one or more processors, one or more memories and one or more programs, wherein the one or more programs are stored in the one or more memories and are configured to be executed by the one or more processors, and the one or more programs include instructions for executing an online emergency control quantity calculation method.

[0096] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0097] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0098] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1The function specified in one or more boxes.

[0099] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0100] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. Online emergency control quantity calculation method, characterized in that: include: Generate the worst short-term power fluctuation mode of renewable energy based on the current online mode of the system; Under the worst short-term power fluctuation mode of renewable energy, obtain the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power as the power angle changes; Based on the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle, a model of increased deceleration area when the system is critically stable after emergency control is implemented is constructed. Based on the increased deceleration area model, the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst short-term power fluctuation mode of new energy is calculated. Based on the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst short-term power fluctuation mode of new energy, the equivalent single-machine electromagnetic power mutation amount considering the short-term power fluctuation of new energy is calculated; Calculate the online emergency control quantity based on the equivalent single-machine electromagnetic power mutation quantity considering the short-term power fluctuation of new energy; The above-mentioned model for increasing the deceleration area is: Among them, A′3 is the deceleration area increased when the system is critically stable after the emergency control is implemented, ΔP m is the equivalent single-machine electromechanical power increase under the worst short-term power fluctuation of new energy, δ k The trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle and ΔP when the emergency control is not implemented in the current online mode m The angle corresponding to the intersection point, δ is the power angle variable, a, b, c are parameters, ΔP′ is the equivalent single-machine electromagnetic power mutation considering the short-term power fluctuation of new energy, δ′ cg To implement emergency control of rotor angle under the worst short-term power fluctuation of renewable energy, It is the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst short-term power fluctuation mode of renewable energy; The formula for calculating the equivalent single-machine electromagnetic power mutation amount considering the short-term power fluctuation of new energy is as follows:

2. The online emergency control quantity calculation method according to claim 1, characterized in that: The worst short-term power fluctuations of renewable energy are: Based on the current online mode of the system, the new energy of the critical group decreases, the reduced capacity of the new energy is A% of the new energy access capacity of the critical group, the output of the synchronous machine of the critical group increases by the output of the reduced new energy, and at the same time, the new energy of the remaining group increases, the increased capacity of the new energy is A% of the new energy access capacity of the remaining group, and the output of the synchronous machine of the remaining group decreases by the output of the increased new energy; where A is the threshold.

3. The online emergency control quantity calculation method according to claim 2, characterized in that: Under the worst short-term power fluctuation mode of renewable energy, obtain the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power as the power angle changes, including: Under the worst short-term power fluctuation mode of new energy, the equivalent single-machine electromagnetic power remains unchanged, and the equivalent single-machine mechanical power increases by The trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power as the power angle changes is ΔP m The difference between the electromagnetic power of the equivalent single machine and the electromagnetic power of the equivalent single machine; S is the critical group inertia of the system when emergency control is not implemented, M A is the remaining group inertia of the system when emergency control is not implemented, ΔP ms is the increase in output of the critical group synchronous machine, ΔP ma The output reduction of the remaining group of synchronous machines.

4. The online emergency control quantity calculation method according to claim 1, characterized in that: The formula for calculating the online emergency control quantity is: Among them, M S is the critical group inertia of the system when emergency control is not implemented, M A is the remaining group inertia of the system when emergency control is not implemented, ΔP′ e is the online emergency control quantity, M′ g The inertia of the disconnected unit after emergency control is M' g .

5. Online emergency control quantity calculation system, characterized by: include: The worst-case mode generation module generates the worst-case short-term power fluctuation mode of renewable energy based on the current online mode of the system; The trajectory acquisition module obtains the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power as the power angle changes under the worst short-term power fluctuation of new energy; The mutation calculation module constructs a model for increasing the deceleration area when the system is critically stable after emergency control is implemented based on the trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle. Based on the increased deceleration area model, the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst new energy short-term power fluctuation mode is calculated. Based on the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst new energy short-term power fluctuation mode, the equivalent single-machine electromagnetic power mutation considering the new energy short-term power fluctuation is calculated. The control quantity calculation module calculates the online emergency control quantity based on the equivalent single-machine electromagnetic power mutation quantity considering the short-term power fluctuation of new energy; The above-mentioned model for increasing the deceleration area is: Among them, A′3 is the deceleration area increased when the system is critically stable after the emergency control is implemented, ΔP m is the equivalent single-machine electromechanical power increase under the worst short-term power fluctuation of new energy, δ k The trajectory of the difference between the equivalent single-machine electromagnetic power and mechanical power changing with the power angle and ΔP when the emergency control is not implemented in the current online mode m The angle corresponding to the intersection point, δ is the power angle variable, a, b, c are parameters, ΔP′ is the equivalent single-machine electromagnetic power mutation considering the short-term power fluctuation of new energy, δ′ cg To implement emergency control of rotor angle under the worst short-term power fluctuation of renewable energy, It is the dynamic saddle point power angle when the system is critically stable after emergency control is implemented under the worst short-term power fluctuation mode of renewable energy; The formula for calculating the equivalent single-machine electromagnetic power mutation amount considering the short-term power fluctuation of new energy is as follows:

6. The online emergency control quantity calculation system according to claim 5, characterized in that: The worst short-term power fluctuation mode of renewable energy in the worst mode generation module is: Based on the current online mode of the system, the new energy of the critical group decreases, the reduced capacity of the new energy is A% of the new energy access capacity of the critical group, the output of the synchronous machine of the critical group increases by the output of the reduced new energy, and at the same time, the new energy of the remaining group increases, the increased capacity of the new energy is A% of the new energy access capacity of the remaining group, and the output of the synchronous machine of the remaining group decreases by the output of the increased new energy; where A is the threshold.

7. A computer-readable storage medium storing one or more programs, characterized in that: The one or more programs include instructions that, when executed by a computing device, cause the computing device to perform any one of the methods according to claims 1 to 4 .

8. A computing device, characterized in that include: One or more processors, one or more memories, and one or more programs, wherein the one or more programs are stored in the one or more memories and configured to be executed by the one or more processors, the one or more programs comprising instructions for performing any of the methods according to claims 1 to 4.

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