A method and system for determining power system disturbance category

Abstract

The present invention discloses a method and system for distinguishing the type of power system disturbance, which belongs to the technical field of power systems. The method of the present invention includes: calculating the frequency change rate at the start moment after the power system disturbance and the critical frequency change rate after the power system disturbance; calculating the frequency change rate at the power recovery moment after the power disturbance; calculating the disturbance power after the power system disturbance based on the calculation formula of the disturbance power; bringing the disturbance power into the system frequency response model, calculating the frequency change rate threshold at the critical moment, and distinguishing the type of power system disturbance based on the frequency change rate threshold at the critical moment. The present invention can effectively distinguish short-term disturbances from long-term disturbances. In the event of a short-term disturbance, the frequency defense line is locked to avoid the frequency overmodulation problem caused by the action of the frequency defense line after the short-term disturbance is restored, thereby ensuring the safety and stability of the system frequency.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and more particularly, to a method and system for determining a power system disturbance category. Background Art

[0002] Frequency defense is an effective measure for maintaining a safe and stable system frequency. It primarily includes three lines of defense. The first line of defense is frequency preventive control. By optimizing the grid's operating mode and ensuring the system's spinning reserve capacity and distribution, the grid is equipped with the primary and secondary frequency regulation capabilities to meet operational requirements. Key measures include unit grouping, demand response, and orderly power consumption. The second line of defense is fault-triggered frequency emergency control. After a predicted grid fault occurs, the safety and control system, based on a preset strategy table, executes appropriate DC power support, pumped storage, interruptible load, or generator disconnection within 300ms. Frequency correction control, based on electrical quantity responses, is the third line of defense and primarily includes measures such as low-frequency load shedding / high-frequency generator disconnection and low-frequency load shedding.

[0003] The aforementioned frequency defense lines are primarily designed for long-term step disturbances and are only applicable to long-term step disturbances such as power outages and DC lockouts. However, with the increasing proportion of renewable energy and the implementation of high-voltage, high-capacity DC transmission, system disturbance types have become diverse and complex. In addition to long-term step disturbances, short-term power disturbances such as renewable energy high / low-pass and DC commutation failures have also emerged. After a short-term disturbance fault occurs, the disturbance power increases instantaneously. Then, as the renewable energy low-pass and DC commutation failure end, the disturbance power gradually decreases to zero. This process causes the frequency to increase, but as the disturbance power decreases, the frequency gradually recovers. If the existing three frequency defense lines are used, the removed load will cause the frequency to overshoot after the disturbance power is restored, threatening the system frequency security.

[0004] Therefore, after a disturbance occurs, how to distinguish long-term disturbances from short-term disturbances and avoid frequency overmodulation caused by the action of frequency control measures in the event of a short-term disturbance is an urgent problem to be solved. Summary of the Invention

[0005] In response to the above problems, the present invention proposes a method for distinguishing the type of power system disturbance, comprising:

[0006] Acquiring operation data of the power system after the disturbance, and calculating, based on the operation data, a frequency change rate at the start time of the power system disturbance and a critical frequency change rate after the power system disturbance;

[0007] Calculating the frequency change rate at the power system power recovery time after the disturbance based on the frequency change rate at the start time and the critical frequency change rate;

[0008] Establishing a simplified system frequency response model based on the operation mode and frequency modulation parameters of the power system, establishing a calculation formula for disturbance power based on the system frequency response model, and calculating the disturbance power after the power system disturbance based on the calculation formula for disturbance power;

[0009] The disturbance power is introduced into the system frequency response model to calculate a frequency change rate threshold at a critical moment, and the type of the power system disturbance is determined based on the frequency change rate threshold at the critical moment.

[0010] Optionally, calculating the frequency change rate at the power recovery moment after the power system disturbance based on the frequency change rate and the critical frequency change rate at the start moment includes:

[0011] comparing the frequency change rate at the start time with a critical frequency change rate;

[0012] If the frequency change rate at the start time is greater than the critical frequency change rate, a safety control amount is calculated, the frequency change rate at the start time is updated based on the safety control amount, and the frequency change rate at the power recovery time after the power system disturbance is calculated based on the updated frequency change rate at the start time;

[0013] If the frequency change rate at the starting moment is less than the critical frequency change rate, the frequency change rate at the starting moment is not updated. The frequency change rate at the starting moment is updated based on the frequency change rate at the starting moment to calculate the frequency change rate at the power recovery moment after the power system disturbance.

[0014] Optionally, the disturbance power is introduced into the system frequency response model to calculate a frequency change rate threshold at a critical moment, including:

[0015] Substituting the disturbance power into the system frequency response model, calculating the frequency response curve under the step disturbance, and obtaining the corresponding frequency change rate at the critical moment;

[0016] The difference between the frequency change rate at the start time and the frequency change rate at the time when the new energy low-power consumption begins to recover is taken as the frequency change rate threshold at the critical time.

[0017] Optionally, the type of the power system disturbance is determined based on the frequency change rate threshold at the critical moment, including:

[0018] If the frequency change rate at the start time is approximately equal to the sum of the frequency change rate threshold at the critical time and the frequency change rate at the time when the new energy low-power begins to recover, then the power system disturbance is judged to be a long-term step disturbance;

[0019] If the frequency change rate at the start time is greater than the sum of the frequency change rate threshold at the critical time and the frequency change rate at the time when the new energy low-throughput power begins to recover, the power system disturbance is judged to be a new energy low-throughput disturbance.

[0020] In another aspect, the present invention further provides a system for determining a power system disturbance category, comprising:

[0021] A first calculation unit is configured to obtain operation data of the power system after the disturbance, and calculate, based on the operation data, a frequency change rate at the start time of the power system disturbance and a critical frequency change rate of the power system after the disturbance;

[0022] a second calculation unit, configured to calculate the frequency change rate at the power recovery moment after the power system disturbance based on the frequency change rate at the start moment and the critical frequency change rate;

[0023] a third calculation unit, configured to establish a simplified system frequency response model according to the operation mode and frequency regulation parameters of the power system, establish a calculation formula for disturbance power according to the system frequency response model, and calculate the disturbance power after the power system is disturbed based on the calculation formula for disturbance power;

[0024] The discrimination unit is used to bring the disturbance power into the system frequency response model, calculate the frequency change rate threshold at the critical moment, and discriminate the type of the power system disturbance based on the frequency change rate threshold at the critical moment.

[0025] Optionally, the second calculation unit calculates the frequency change rate at the power recovery moment after the power system disturbance based on the frequency change rate and the critical frequency change rate at the start moment, including:

[0026] comparing the frequency change rate at the start time with a critical frequency change rate;

[0027] If the frequency change rate at the start time is greater than the critical frequency change rate, a safety control amount is calculated, the frequency change rate at the start time is updated based on the safety control amount, and the frequency change rate at the power recovery time after the power system disturbance is calculated based on the updated frequency change rate at the start time;

[0028] If the frequency change rate at the starting moment is less than the critical frequency change rate, the frequency change rate at the starting moment is not updated. The frequency change rate at the starting moment is updated based on the frequency change rate at the starting moment to calculate the frequency change rate at the power recovery moment after the power system disturbance.

[0029] Optionally, the third calculation unit brings the disturbance power into the system frequency response model to calculate a frequency change rate threshold at a critical calculation moment, including:

[0030] Substituting the disturbance power into the system frequency response model, calculating the frequency response curve under the step disturbance, and obtaining the corresponding frequency change rate at the critical moment;

[0031] The difference between the frequency change rate at the start time and the frequency change rate at the time when the new energy low-power consumption begins to recover is taken as the frequency change rate threshold at the critical time.

[0032] Optionally, the determining unit determines the type of the power system disturbance based on the frequency change rate threshold at the critical moment, including:

[0033] If the frequency change rate at the start time is approximately equal to the sum of the frequency change rate threshold at the critical time and the frequency change rate at the time when the new energy low-power begins to recover, then the power system disturbance is judged to be a long-term step disturbance;

[0034] If the frequency change rate at the start time is greater than the sum of the frequency change rate threshold at the critical time and the frequency change rate at the time when the new energy low-throughput power begins to recover, the power system disturbance is judged to be a new energy low-throughput disturbance.

[0035] In yet another aspect, the present invention further provides a computing device comprising: one or more processors;

[0036] a processor for executing one or more programs;

[0037] When the one or more programs are executed by the one or more processors, the above-described method is implemented.

[0038] In another aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed, the method described above is implemented.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The present invention provides a method for distinguishing the type of power system disturbance, comprising: obtaining operation data after the power system disturbance, and calculating the frequency change rate at the start time of the power system disturbance and the critical frequency change rate after the power system disturbance based on the operation data; calculating the frequency change rate at the power recovery time of the power system disturbance based on the frequency change rate and the critical frequency change rate; establishing a simplified system frequency response model according to the operation mode and frequency modulation parameters of the power system, and establishing a calculation formula for the disturbance power based on the system frequency response model; calculating the disturbance power after the power system disturbance based on the calculation formula for the disturbance power; substituting the disturbance power into the system frequency response model, calculating the frequency change rate threshold at the critical moment, and distinguishing the type of power system disturbance based on the frequency change rate threshold at the critical moment. The present invention can effectively distinguish short-term disturbances from long-term disturbances, and in the event of a short-term disturbance, lock the frequency defense line to avoid the frequency overmodulation problem caused by the action of the frequency defense line after the short-term disturbance is restored, thereby ensuring the safety and stability of the system frequency. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a flow chart of the method of the present invention;

[0042] Figure 2 is a flow chart of an embodiment of the method of the present invention;

[0043] Figure 3 A frequency response model diagram of an embodiment of the method of the present invention;

[0044] Figure 4 A schematic diagram of disturbance power according to an embodiment of the method of the present invention;

[0045] Figure 5 A schematic diagram of frequency deviation in an embodiment of the method of the present invention;

[0046] Figure 6 A schematic diagram of the frequency change rate of an embodiment of the method of the present invention;

[0047] Figure 7 It is a structural diagram of the system of the present invention. DETAILED DESCRIPTION

[0048] Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to provide a thorough and complete disclosure of the present invention and to fully convey the scope of the present invention to those skilled in the art. The terminology used in the exemplary embodiments shown in the accompanying drawings is not intended to limit the present invention. In the accompanying drawings, identical elements are denoted by the same reference numerals.

[0049] Unless otherwise specified, the terms used herein (including technical terms) have the meanings commonly understood by those skilled in the art. In addition, it is understood that terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0050] Example 1:

[0051] The present invention proposes a method for identifying the type of power system disturbance, such as Figure 1 As shown, including:

[0052] Step s101: Acquire operation data of a power system after a disturbance, and calculate, based on the operation data, a frequency change rate at the start time of the power system disturbance and a critical frequency change rate after the power system disturbance;

[0053] Step s102: Calculate the frequency change rate at the power recovery time after the power system disturbance based on the frequency change rate and the critical frequency change rate at the start time;

[0054] Step s103: establishing a simplified system frequency response model based on the operation mode and frequency modulation parameters of the power system, establishing a calculation formula for disturbance power based on the system frequency response model, and calculating the disturbance power after the power system disturbance based on the calculation formula for disturbance power;

[0055] Step s104: Substitute the disturbance power into the system frequency response model to calculate a frequency change rate threshold at a critical moment, and determine the type of the power system disturbance based on the frequency change rate threshold at the critical moment.

[0056] The step of calculating the frequency change rate at the power recovery moment after the power system disturbance based on the frequency change rate and the critical frequency change rate at the start moment includes:

[0057] comparing the frequency change rate at the start time with a critical frequency change rate;

[0058] If the frequency change rate at the start time is greater than the critical frequency change rate, a safety control amount is calculated, the frequency change rate at the start time is updated based on the safety control amount, and the frequency change rate at the power recovery time after the power system disturbance is calculated based on the updated frequency change rate at the start time;

[0059] If the frequency change rate at the starting moment is less than the critical frequency change rate, the frequency change rate at the starting moment is not updated. The frequency change rate at the starting moment is updated based on the frequency change rate at the starting moment to calculate the frequency change rate at the power recovery moment after the power system disturbance.

[0060] The disturbance power is introduced into the system frequency response model to calculate the frequency change rate threshold at the critical moment, including:

[0061] Substituting the disturbance power into the system frequency response model, calculating the frequency response curve under the step disturbance, and obtaining the corresponding frequency change rate at the critical moment;

[0062] The difference between the frequency change rate at the start time and the frequency change rate at the time when the new energy low-power consumption begins to recover is taken as the frequency change rate threshold at the critical time.

[0063] The method of determining the type of power system disturbance based on the frequency change rate threshold at the critical moment includes:

[0064] If the frequency change rate at the start time is approximately equal to the sum of the frequency change rate threshold at the critical time and the frequency change rate at the time when the new energy low-power begins to recover, then the power system disturbance is judged to be a long-term step disturbance;

[0065] If the frequency change rate at the start time is greater than the sum of the frequency change rate threshold at the critical time and the frequency change rate at the time when the new energy low-throughput power begins to recover, the power system disturbance is judged to be a new energy low-throughput disturbance.

[0066] The present invention will be further described below with reference to specific cases:

[0067] The process of case implementation is as follows Figure 2 As shown, the following steps are included:

[0068] (1) Calculate the frequency change rate at the start of the disturbance;

[0069] Calculate the frequency change rate based on the frequency curve measured at the initial stage of the disturbance, and calculate the system frequency change rate df / dt0 at the moment of the disturbance;

[0070]

[0071] Where t0 is the disturbance time (e.g. 0s), f0 is the frequency before the disturbance (usually 50Hz), t 01 Take the 200ms-300ms time window, f 01 t 01 Time frequency.

[0072] (2) Calculate the critical frequency change rate;

[0073] At the initial stage of disturbance, the effect of primary frequency modulation is small, and only the inertia effect is considered. The frequency monitoring period (t0~t c ) does not trigger the critical frequency change rate of under-frequency load shedding, the formula is as follows:

[0074]

[0075] Where f0 is the rated frequency 50Hz, f cri is the low-frequency load shedding frequency action value (e.g. 49.25Hz); c To calculate the frequency change rate moment (determined according to the new energy low-breakthrough recovery time, for example, 0.5s), a certain margin can be considered and set to a longer time (for example, 0.7s).

[0076] (3) Judgment stage: compare the frequency change rate at the beginning of the disturbance with the critical frequency change rate;

[0077] If |df / dt0|>|df / dt cri |, that is, the frequency change rate at the disturbance moment is greater than the critical frequency change rate, indicating that the disturbance occurred during the frequency monitoring period (0~t c ), will trigger the low-frequency load shedding action. At this time, it is necessary to take safety and control measures. The principle of calculating the amount of measures is that the safety and control amount just does not trigger the low-frequency load shedding (that is, take as little safety and control amount as possible to ensure that the frequency overshoot is minimized after the new energy low-frequency penetration is restored). The specific calculation method is steps (4) to (5).

[0078] If |df / dt0|<|df / dt cri |, that is, the initial frequency change rate is less than the critical frequency change rate, and the disturbance will not exceed the low-frequency load reduction setting during the frequency monitoring period. Then proceed to step (6).

[0079] (4) Control measures formulation stage;

[0080] Since the frequency monitoring period is short, the generator speed governor has not yet been effectively activated and the load effect is also very small, only the inertia effect is considered. The calculation formula for the safety control quantity is:

[0081]

[0082] Where, is the frequency change rate at the start of the disturbance in step (1), is the critical frequency change rate in step (2), S B is the system capacity, f0 is the rated frequency, and H is the system inertia constant.

[0083] (5) Safety control action, update the frequency change rate df / dt0 at the disturbance moment;

[0084] Apply the security control measure ΔP calculated in step (4) s After that, the frequency change rate df / dt0 at the disturbance moment is updated to ΔP s The frequency change rate after the action is performed, and step (6) is performed.

[0085] (6) Calculate the frequency change rate at the moment of power recovery;

[0086] Calculate t c Time frequency change rate df / dt c , where t c = t1 + a certain time margin, where t1 is the time when the new energy low-power begins to recover (usually the short-circuit removal time, for example, 0.5s), and the certain time margin is set according to demand (for example, 0.2s). Go to steps (7) to (9) to calculate the frequency change rate threshold considering the speed regulator action.

[0087] (7) According to the system operation mode and frequency modulation parameters, a simplified system frequency response model is obtained, such as Figure 3 As shown, the frequency is calculated according to the frequency model;

[0088] Among them, the parameters in the figure are: K mh 、R h 、T w K is the capacity ratio of hydropower units, the adjustment coefficient, and the water flow time constant, respectively. T2, T3, and T4 are the time constants of the hydropower governor. ms 、F H 、T R 、R s 、T g They are the capacity ratio of thermal power units, the proportion of high-pressure cylinder steam, the reheater time constant, the governor adjustment coefficient and the time constant. w , K VI They are the wind power primary frequency regulation coefficient and virtual inertia coefficient respectively. Each parameter is obtained based on the system operation mode and unit data.

[0089] (8) Calculate the disturbance power based on the frequency change rate and system inertia at the disturbance moment;

[0090] According to the system frequency model in step (7), since the speed regulator has not started at the initial stage of the disturbance and the load frequency regulation effect is small, it can be considered that only inertia acts. Combined with the frequency change rate in step (1) or the updated frequency change rate after the safety control action in step (4), the calculation formula for the disturbance power is:

[0091]

[0092] (9) Substitute the disturbance power into the frequency response model and calculate t c The moment frequency change rate threshold;

[0093] Substitute the disturbance power in step (8) into the frequency model in step (7) and calculate the frequency response curve under the step disturbance to obtain t c The corresponding frequency change rate at the moment is df / dt2, so the threshold △|df / dt| ref=|df / dt|0-|df / dt|2.

[0094] (10) Frequency change rate judgment link;

[0095] If |df / dt|0≈(|df / dt|1+△|df / dt| ref ), it is determined to be a long-term step disturbance and the action is taken according to the step disturbance defense line;

[0096] If |df / dt|0>(|df / dt|1+△|df / dt| ref ), it is determined to be a new energy low penetration disturbance, and the frequency defense line does not act. If it acts, it will cause the frequency to over-adjust after the new energy low penetration is restored.

[0097] The disturbance type, frequency curve and frequency change rate involved in the above steps are as follows: Figure 4 , as shown in Figures 5 and 6.

[0098] Example 2:

[0099] The present invention also proposes a system 200 for determining the type of power system disturbance, such as Figure 7 As shown, including:

[0100] A first calculation unit 201 is configured to obtain operation data of a power system after a disturbance, and calculate, based on the operation data, a frequency change rate at the start time of the power system disturbance and a critical frequency change rate of the power system after the disturbance;

[0101] The second calculation unit 202 is configured to calculate the frequency change rate at the power recovery time after the power system disturbance based on the frequency change rate at the start time and the critical frequency change rate;

[0102] The third calculation unit 203 is configured to establish a simplified system frequency response model according to the operation mode and frequency regulation parameters of the power system, establish a calculation formula for the disturbance power according to the system frequency response model, and calculate the disturbance power after the power system is disturbed based on the calculation formula for the disturbance power;

[0103] The determination unit 204 is configured to introduce the disturbance power into the system frequency response model, calculate a frequency change rate threshold at a critical moment, and determine a type of power system disturbance based on the frequency change rate threshold at the critical moment.

[0104] The second calculation unit 202 calculates the frequency change rate at the power recovery time after the power system disturbance based on the frequency change rate and the critical frequency change rate at the start time, including:

[0105] comparing the frequency change rate at the start time with a critical frequency change rate;

[0106] If the frequency change rate at the start time is greater than the critical frequency change rate, a safety control amount is calculated, the frequency change rate at the start time is updated based on the safety control amount, and the frequency change rate at the power recovery time after the power system disturbance is calculated based on the updated frequency change rate at the start time;

[0107] If the frequency change rate at the starting moment is less than the critical frequency change rate, the frequency change rate at the starting moment is not updated. The frequency change rate at the starting moment is updated based on the frequency change rate at the starting moment to calculate the frequency change rate at the power recovery moment after the power system disturbance.

[0108] The third calculation unit 203 brings the disturbance power into the system frequency response model to calculate the frequency change rate threshold at the critical moment, including:

[0109] Substituting the disturbance power into the system frequency response model, calculating the frequency response curve under the step disturbance, and obtaining the corresponding frequency change rate at the critical moment;

[0110] The difference between the frequency change rate at the start time and the frequency change rate at the time when the new energy low-power consumption begins to recover is taken as the frequency change rate threshold at the critical time.

[0111] The determining unit 204 determines the type of the power system disturbance based on the frequency change rate threshold at the critical moment, including:

[0112] If the frequency change rate at the start time is approximately equal to the sum of the frequency change rate threshold at the critical time and the frequency change rate at the time when the new energy low-power begins to recover, then the power system disturbance is judged to be a long-term step disturbance;

[0113] If the frequency change rate at the start time is greater than the sum of the frequency change rate threshold at the critical time and the frequency change rate at the time when the new energy low-throughput power begins to recover, the power system disturbance is judged to be a new energy low-throughput disturbance.

[0114] The present invention can effectively distinguish between short-term disturbances and long-term disturbances. In the event of a short-term disturbance, the frequency defense line is locked to avoid the problem of frequency overmodulation caused by the action of the frequency defense line after the short-term disturbance is recovered, thereby ensuring the safety and stability of the system frequency.

[0115] Example 3:

[0116] Based on the same inventive concept, the present invention also provides a computer device, which includes a processor and a memory, wherein the memory is used to store a computer program, the computer program includes program instructions, and the processor is used to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to implement the corresponding method flow or corresponding function, so as to implement the steps of the method in the above embodiment.

[0117] Example 4:

[0118] Based on the same inventive concept, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It can be understood that the computer-readable storage medium here can include both built-in storage media in the computer device and, of course, extended storage media supported by the computer device. The computer-readable storage medium provides a storage space that stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space. These instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of the method in the above embodiment.

[0119] It will be understood by those skilled in the art that the embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete 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 disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of the present invention may be implemented in various computer languages, for example, the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0120] 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.

[0121] 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 1 The function specified in one or more boxes.

[0122] 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.

[0123] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0124] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A method for determining the type of power system disturbance, characterized in that: The method comprises: Acquiring operation data of the power system after the disturbance, and calculating, based on the operation data, a frequency change rate at the start time of the power system disturbance and a critical frequency change rate after the power system disturbance; Calculating the frequency change rate at the power system power recovery time after the disturbance based on the frequency change rate and the critical frequency change rate at the start time; Establishing a simplified system frequency response model based on the operation mode and frequency modulation parameters of the power system, establishing a calculation formula for disturbance power based on the system frequency response model, and calculating the disturbance power after the power system disturbance based on the calculation formula for disturbance power; The disturbance power is introduced into the system frequency response model to calculate the frequency change rate threshold at the critical moment. The type of power system disturbance is determined based on the sum of the frequency change rate threshold at the critical moment and the frequency change rate at the moment when the new energy low-power begins to recover.

2. The method according to claim 1, characterized in that The calculating, based on the frequency change rate and the critical frequency change rate at the start time, of the frequency change rate at the power system power recovery time after the disturbance, includes: comparing the frequency change rate at the start time with a critical frequency change rate; If the frequency change rate at the start time is greater than the critical frequency change rate, a safety control amount is calculated, the frequency change rate at the start time is updated based on the safety control amount, and the frequency change rate at the power recovery time after the power system disturbance is calculated based on the updated frequency change rate at the start time; If the frequency change rate at the starting moment is less than the critical frequency change rate, the frequency change rate at the starting moment is not updated. The frequency change rate at the starting moment is updated based on the frequency change rate at the starting moment to calculate the frequency change rate at the power recovery moment after the power system disturbance.

3. The method according to claim 1, characterized in that The step of bringing the disturbance power into the system frequency response model and calculating a frequency change rate threshold at a critical moment includes: Substituting the disturbance power into the system frequency response model, calculating the frequency response curve under the step disturbance, and obtaining the corresponding frequency change rate at the critical moment; The difference between the frequency change rate at the start time and the frequency change rate at the time when the new energy low-power consumption begins to recover is taken as the frequency change rate threshold at the critical time.

4. The method according to claim 1, wherein The determining the type of the power system disturbance based on the frequency change rate threshold at the critical moment includes: If the frequency change rate at the start time is approximately equal to the sum of the frequency change rate threshold at the critical time and the frequency change rate at the time when the new energy low-power begins to recover, then the power system disturbance is judged to be a long-term step disturbance; If the frequency change rate at the start time is greater than the sum of the frequency change rate threshold at the critical time and the frequency change rate at the time when the new energy low-throughput power begins to recover, the power system disturbance is judged to be a new energy low-throughput disturbance.

5. A system for determining the type of disturbance in a power system, characterized in that: The system comprises: A first calculation unit is configured to obtain operation data of the power system after the disturbance, and calculate, based on the operation data, a frequency change rate at the start time of the power system disturbance and a critical frequency change rate of the power system after the disturbance; a second calculation unit, configured to calculate the frequency change rate at the power recovery moment after the power system disturbance based on the frequency change rate at the start moment and the critical frequency change rate; a third calculation unit, configured to establish a simplified system frequency response model according to the operation mode and frequency regulation parameters of the power system, establish a calculation formula for disturbance power according to the system frequency response model, and calculate the disturbance power after the power system is disturbed based on the calculation formula for disturbance power; A discrimination unit is used to bring the disturbance power into the system frequency response model, calculate the frequency change rate threshold at a critical moment, and discriminate the type of power system disturbance based on the sum of the frequency change rate threshold at the critical moment and the frequency change rate at the moment when the new energy low-power begins to recover.

6. The system according to claim 5, characterized in that The second calculation unit calculates the frequency change rate at the power recovery time after the power system disturbance based on the frequency change rate and the critical frequency change rate at the start time, including: comparing the frequency change rate at the start time with a critical frequency change rate; If the frequency change rate at the start time is greater than the critical frequency change rate, a safety control amount is calculated, the frequency change rate at the start time is updated based on the safety control amount, and the frequency change rate at the power recovery time after the power system disturbance is calculated based on the updated frequency change rate at the start time; If the frequency change rate at the starting moment is less than the critical frequency change rate, the frequency change rate at the starting moment is not updated. The frequency change rate at the starting moment is updated based on the frequency change rate at the starting moment to calculate the frequency change rate at the power recovery moment after the power system disturbance.

7. The system according to claim 5, characterized in that The determination unit brings the disturbance power into the system frequency response model to calculate a frequency change rate threshold at a critical moment, including: Substituting the disturbance power into the system frequency response model, calculating the frequency response curve under the step disturbance, and obtaining the corresponding frequency change rate at the critical moment; The difference between the frequency change rate at the start time and the frequency change rate at the time when the new energy low-power consumption begins to recover is taken as the frequency change rate threshold at the critical time.

8. The system according to claim 5, wherein: The determining unit determines the type of the power system disturbance based on the frequency change rate threshold at the critical moment, including: If the frequency change rate at the start time is approximately equal to the sum of the frequency change rate threshold at the critical time and the frequency change rate at the time when the new energy low-power begins to recover, then the power system disturbance is judged to be a long-term step disturbance; If the frequency change rate at the start time is greater than the sum of the frequency change rate threshold at the critical time and the frequency change rate at the time when the new energy low-throughput power begins to recover, the power system disturbance is judged to be a new energy low-throughput disturbance.

9. A computer device, characterized in that: include: one or more processors; a processor for executing one or more programs; When the one or more programs are executed by the one or more processors, the method according to any one of claims 1 to 4 is implemented.

10. A computer-readable storage medium, characterized in that A computer program is stored thereon, and when the computer program is executed, the method according to any one of claims 1 to 4 is implemented.

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