CN-122000927-A - Frequency-stable emergency load system and method based on disturbance position rapid identification

CN122000927ACN 122000927 ACN122000927 ACN 122000927ACN-122000927-A

Abstract

The invention discloses a frequency stability emergency load shedding system based on disturbance position quick identification, which comprises a frequency stability control measure total amount generation module, a frequency control sensitive point mining module and a frequency stability control measure total amount generation module, wherein the frequency stability control measure total amount generation module is used for reading power system state information and frequency response data, identifying a system frequency response model, calculating the stability control measure total amount meeting the frequency stability requirement, the frequency control sensitive point mining module is used for taking key bus frequency time sequence data of the power system as input, taking a disturbance position near-cut load position as output of a frequency stability control sensitive point mining network, and the frequency stability control measure generation module is used for reading the stability control measure total amount meeting the system frequency stability requirement and the control position sensitivity sequencing output by the frequency control sensitive point mining module, and making corresponding emergency load shedding measure when the power system is disturbed so as to enable the system frequency to be restored to a safe range.

Inventors

SUN ZHENGLONG
ZHANG RONGBIN
LI ZEWEI
ZHANG RUI
CAI GUOWEI

Assignees

东北电力大学

Dates

Publication Date: 20260508
Application Date: 20251231

Claims (5)

1. The frequency stabilization emergency load shedding system based on the disturbance position rapid identification is characterized by comprising a frequency stabilization measure total amount generation module, a frequency stabilization control measure total amount generation module and a frequency stabilization control measure total amount generation module, wherein the frequency stabilization control measure total amount generation module is used for reading power system state information and frequency response data, identifying a system frequency response model and calculating the stabilization control measure total amount meeting the frequency stabilization requirement; The frequency control sensitive point mining module is used for taking key bus frequency time sequence data of the power system as input, and taking a disturbance position near cut load position as output of a frequency stability control sensitive point mining network; The frequency stability control measure generating module is used for reading the total quantity of the stability control measures meeting the system frequency stability requirement calculated by the frequency stability control measure total quantity generating module and the sensitivity ordering of each control position output by the frequency control sensitive point mining module, and making corresponding emergency load shedding measures when the electric power system is disturbed so as to restore the system frequency to a safe range.
2. The emergency load shedding system based on the rapid identification of the disturbance position is characterized in that state information and frequency response data of an electric power system are system equivalent inertia, primary frequency modulation aggregation parameters of each unit and system inertia center frequency respectively, the system equivalent inertia is obtained through aggregation calculation of inertia of each element in operation, the inertia time constant of a synchronous generator is obtained, if the inertia of the element cannot be obtained through model parameters, the inertia of the element is obtained through a data-driven inertia evaluation method, a detailed frequency modulation model is built according to the primary frequency modulation aggregation parameters, and the aggregation parameters are determined through overall equivalent reduction of the detailed model.
3. The rapid disturbance location identification-based frequency stabilization emergency load shedding system according to claim 2, wherein the sensitivity is a response parameter for measuring the power system to different load shedding measures, and the magnitude of the minimum point lifting quantity of the system inertia center frequency under the same load shedding quantity and different load shedding locations is quantized.
4. The rapid disturbance location identification based frequency stabilization emergency load shedding system according to claim 3, wherein the system frequency stabilization requirement is that a system inertia center frequency is not lower than 49.2Hz.
5. A method of using the rapid disturbance location identification based frequency stabilized emergency load shedding system according to any one of claims 1-4, comprising: step one, determining frequency response model parameters including system equivalent inertia and primary frequency modulation parameters of each unit, wherein the frequency response model parameters comprise a stability control module; Step two, obtaining the power disturbance quantity of the system according to the frequency change rate, taking the system disturbance quantity and the cut load quantity as the input of a frequency response model, taking the frequency minimum point as the output of the frequency response model, and obtaining the cut load quantity meeting the requirement of system frequency stability through iterative calculation; Selecting a plurality of bus nodes in the power system as observation nodes and a plurality of load shedding positions as load shedding sequencing positions, extracting bus frequency time sequence data before the power system is disturbed as network input, and taking near load shedding positions of each disturbance position as network output for constructing a frequency control sensitive point mining data set; Step four, constructing a CNN-based frequency control sensitive point mining model, and performing network training by using a fault positioning frequency control sensitive point mining data set generated offline; Step five, inputting the key bus frequency time sequence data after disturbance occurs to a frequency control sensitive point mining model, and outputting the nearby load cutting positions of each disturbance position in the current scene; And step six, making and generating control measures by utilizing the obtained load shedding amount meeting the system frequency stability requirement and the nearby load shedding positions of each disturbance position in the current scene, and sending an output instruction to an electric power system for execution, so that the system can give corresponding load shedding measures on line for different working conditions to keep the system stable.

Description

Frequency-stable emergency load system and method based on disturbance position rapid identification Technical Field The invention relates to the technical field of power system frequency control, in particular to a frequency stability emergency load system and method based on disturbance position rapid identification. Background As the new energy output ratio is continuously increased, the complexity and uncertainty of the power grid operation condition are continuously enhanced. The complex variability of the operation mode, the uncertainty of disturbance faults, the weak disturbance resistance of power electronic equipment and the high degree of freedom of control lead the difficulty of stable control of a system level to be larger, and the safe and efficient operation of an oversized alternating current-direct current hybrid power grid is guaranteed to face great challenges. Under the promotion of energy transformation and technological progress, high-proportion renewable new energy and high-proportion power electronic equipment are becoming important trends and key characteristics of power system development, and new energy with volatility and randomness replaces a plurality of synchronous generator sets, so that system inertia in a power system is reduced, sudden large power shortage is caused, frequency fluctuation can be caused, large-scale transfer of alternating current power grid trend can be caused, the safety state of the system is seriously deteriorated even if control measures are incorrect, and even system breakdown is caused, therefore, quick correction or emergency control measures must be adopted to eliminate abnormal state operation of the power system. After serious faults, partial loads are cut off as required, and the research of safety defense of the power system is always the focus. How to reduce the cut load quantity to the greatest extent under the disturbance of the power grid becomes a close attention problem of power grid planning and scheduling operators. The corrective measures for severe active deficit include emergency load shedding in the second line of defense and low frequency, low pressure load shedding in the third line of defense. The load shedding needs to coordinate implementation effect and economic cost, and is essentially a nonlinear programming problem. How to perform reasonable load shedding measures to restore the frequency to a normal operation interval is a problem to be researched at present. Therefore, the frequency stability emergency load method based on the rapid identification of the disturbance position has obvious advantages in the frequency stability control of the current complex power grid as a control means capable of taking the control effect and the economy into consideration. The prior scheme control based on the policy table is the most mature emergency control system with the lowest application difficulty and cost, is widely applied to the second defense line of the power system, and prevents the system from losing stability by adopting necessary safety and stability control measures such as cutting machine, load cutting and the like. However, the method has a process of imaginary fault and pre-decision, is difficult to cover all fault types of the AC/DC hybrid power grid, has a risk of decision error, and cannot guarantee safe operation of the power grid under the condition of complex and unexpected faults by fault matching type stability control measures. Disclosure of Invention Aiming at the problems, the invention provides a frequency stability emergency load system and a frequency stability emergency load method based on the rapid identification of the disturbance position, which prove that under the same frequency stability control measure and stability control action time, the closer the electric distance between the implementation stability control measure and the disturbance place is, the more favorable the system frequency stability is, the accuracy of a control strategy when the disturbance occurs to the power system is improved, the time of the control strategy of the power system is reduced, and the frequency safety stability under the complex power system is improved. The invention provides a frequency-stable emergency load shedding system based on disturbance position rapid identification, which comprises the following components: The frequency stability control measure total amount generating module is used for reading the state information and the frequency response data of the power system, identifying a frequency response model of the system and calculating the stability control measure total amount meeting the frequency stability requirement; The frequency control sensitive point mining module is used for providing a system frequency analysis model for a simplified multi-region equivalent system by combining a power distribution principle after system disturbance, a frequency response model and a frequency distribution ru