CN-122000995-A - Transient state synchronization stability margin checking method and system for network construction equipment

CN122000995ACN 122000995 ACN122000995 ACN 122000995ACN-122000995-A

Abstract

A method for checking transient state synchronous stability margin of network construction equipment includes confirming moment and position of kinetic energy injection through fault simulation, taking sum of deceleration area and damping deceleration area as sum of maximum injection kinetic energy and acceleration area as equal area criterion for reaching transient state synchronous critical stability of network construction equipment, taking injection of angular velocity step signals with different amplitude values as target according to moment and position of kinetic energy injection, determining maximum injection kinetic energy iteratively under condition that damping deceleration area passes validity check, taking difference value of maximum injection kinetic energy passing validity check and damping deceleration area passing validity check as transient state synchronous stability margin of network construction equipment. According to the invention, the deceleration effect provided by damping in the transient process can be accurately considered, the critical state of the system is simulated by injecting kinetic energy at a specific moment and position, and the calculation of the damping deceleration area is combined, so that the transient synchronous stability margin of the network construction equipment is quickly and accurately checked.

Inventors

ZHOU SHAOZE
WANG WEI
LI SISI
WEI CHENG
LV XIAOFEI
SHEN YANJUN
LING JINGWEN
CHEN YU
GENG YUE

Assignees

国电南瑞科技股份有限公司
国网电力科学研究院有限公司

Dates

Publication Date: 20260508
Application Date: 20251215

Claims (11)

1. The transient state synchronous stability margin checking method for the network construction equipment is characterized by comprising the following steps of: determining the moment and the position of kinetic energy injection through fault simulation; The method comprises the steps of taking the sum of a deceleration area and a damping deceleration area as the sum of the maximum injection kinetic energy and an acceleration area as an equal area criterion for achieving transient synchronous critical stability of the grid-structured equipment, taking the injection of angular velocity step signals with different amplitude values as a target according to the moment and the position of kinetic energy injection, iteratively determining the maximum injection kinetic energy under the condition that the damping deceleration area passes the validity check, and taking the difference value between the maximum injection kinetic energy passing the validity check and the damping deceleration area passing the validity check as the transient synchronous stability margin of the grid-structured equipment.
2. The method for checking transient synchronization stability margin of a network-structured device according to claim 1, wherein, Setting up a short-circuit fault of the system, and cutting off the fault after the fault lasts for a period of time; Determining fault removal time based on a fault simulation model, taking the fault removal time and any time after fault removal as kinetic energy injection time, and taking an electric angular velocity instruction generation port of a synchronous link of the network-structured equipment as a kinetic energy injection position.
3. The method for checking transient synchronization stability margin of a network-structured device according to claim 1, wherein, The acceleration area is calculated as shown in the following formula: in the formula, In order to accelerate the area of the device, For the mechanical power to be applied, For the purpose of electromagnetic power, For the initial power angle of the fault, The moment power angle is cut off for the fault.
4. The method for checking transient synchronization stability margin of a network-structured device according to claim 3, wherein, The damping deceleration area is calculated as shown in the following formula: in the formula, In order to damp the area of deceleration, For transient synchronous critical stabilization of the network-structured equipment, the first swing peak power angle of the corresponding power angle swing curve, In order to be a damping coefficient, For the rated angular speed of the electrical network, In order to be able to vary the angular velocity, = - , Is the following angle in the integral process Varying angular velocity.
5. The method for checking transient synchronization stability margin of a network forming device according to claim 4, wherein, The deceleration area is calculated as shown in the following formula: in the formula, In order to reduce the area of the gear, Is the peak power angle of the first pendulum Corresponding time of day Is provided.
6. The method for checking transient synchronization stability margin of a network forming device according to claim 5, wherein, Area of deceleration Damping area of deceleration And as the maximum deceleration area At the same time, the actual deceleration area is obtained through fault simulation Calculating the deviation ratio of damping deceleration area The following formula is shown: When (when) Judging that the damping deceleration area is effective when the damping deceleration area is less than or equal to 5 percent, and marking as Otherwise, judging that the damping deceleration area is invalid, and adjusting parameters of the fault simulation model.
7. The method for checking transient synchronization stability margin of a network forming device according to claim 6, wherein, Equal area criterion for achieving transient synchronous critical stability based on network construction equipment + = + Calculating the maximum injection kinetic energy 。
8. The method for checking transient synchronization stability margin of a network-structured device according to claim 7, wherein, Setting the initial implantation amplitude as Is a step signal of angular velocity If the system keeps transient state synchronous stability after injection, then Corresponding kinetic energy Less than The amplitude of the angular velocity step signal needs to be increased; gradually increasing the amplitude of the injected angular velocity step signal until the angular velocity step signal is injected After system instability, then Corresponding kinetic energy Greater than Angular velocity step signal of last injection For critical signals, the maximum injection kinetic energy is updated in the following relation : = Calculating the maximum injection kinetic energy deviation ratio The following formula is shown: When (when) Judging that the maximum injection kinetic energy is effective when the injection kinetic energy is less than or equal to 5 percent, and marking as Otherwise, judging that the maximum injection kinetic energy is invalid, and readjusting parameters of the fault simulation model.
9. A system for checking transient synchronization stability margin of a network-structured device, configured to implement the method for checking transient synchronization stability margin of a network-structured device according to any one of claims 1 to 8, comprising: the injection time position module is used for determining the time and position of kinetic energy injection through fault simulation; the stability criterion module is used for taking the sum of the deceleration area and the damping deceleration area as the sum of the maximum injection kinetic energy and the acceleration area as an equal area criterion for achieving transient synchronous critical stability of the net-structured equipment; The injection kinetic energy module is used for iteratively determining the maximum injection kinetic energy under the condition that the damping deceleration area passes the validity check by taking the equal area criterion as a target when injecting angular velocity step signals with different amplitudes according to the moment and the position of the kinetic energy injection; And the stability margin module is used for taking the difference value between the maximum injection kinetic energy passing the validity check and the damping deceleration area passing the validity check as the transient state synchronous stability margin of the network construction equipment.
10. A terminal comprises a processor and a storage medium, and is characterized in that: The storage medium is used for storing instructions; The processor being operative according to the instructions to perform the steps of the method of any one of claims 1-8.
11. A computer readable storage medium, on which a computer program is stored, characterized in that the program, when being executed by a processor, implements the steps of the method according to any one of claims 1-8.

Description

Transient state synchronization stability margin checking method and system for network construction equipment Technical Field The invention belongs to the technical field of stability analysis of power systems, and particularly relates to a transient synchronous stability margin checking method and system for network construction equipment. Background With the rapid development of new energy power generation technology, the duty ratio of network-structured equipment in a power system is continuously improved. The grid formation provides voltage and frequency support for the system by simulating the external characteristics of the synchronous generator. However, transient synchronous stability problems of the network-structured equipment after large disturbance occurs to the power grid are increasingly prominent, the stability mechanism of the network-structured equipment is obviously different from that of a traditional synchronous generator, and accurate assessment of the transient stability margin of the network-structured equipment is crucial to guaranteeing safe and stable operation of a power system. The core evaluation index of the transient state synchronous stability margin is the balance relation between the acceleration area and the deceleration area, the acceleration area absorbed by the system during the fault period is required to be smaller than the available deceleration area after the fault is removed, and the system side can keep stable. However, the existing stability margin evaluation method has various defects when applied to the network construction equipment, and the traditional stability margin evaluation method is not uniform, so that the comparison analysis is inconvenient. Furthermore, the impact of damping on system transients is difficult to quantify accurately. After the fault is cleared, part of kinetic energy is consumed by damping in the actual deceleration process of the system, and a part of damping deceleration area is provided, but the part of damping deceleration area is often ignored or simplified in the traditional equal area rule, so that the evaluation result of the stability margin is deviated. Therefore, a transient synchronous stability margin checking method which can accurately account for damping influence and is suitable for rapidly judging critical stable states of network-structured equipment is urgently needed. Disclosure of Invention In order to solve the defects in the prior art, the invention provides a method and a system for checking transient synchronous stability margin of a network-structured device, which are suitable for a single-machine model and a single-machine equivalent model (a numerical equivalent model or an analytic equivalent model) of a network-structured multi-machine system, can accurately account for the deceleration effect provided by damping in the transient process, simulate the critical state of the system by injecting kinetic energy at a specific moment and position, and realize the rapid and accurate check of the transient synchronous stability margin of the network-structured device by combining the calculation of the damping deceleration area, thereby providing technical support for the safe and stable operation of an electric power system. The invention adopts the following technical scheme. The invention provides a transient state synchronization stability margin checking method of a network construction device, which comprises the following steps: determining the moment and the position of kinetic energy injection through fault simulation; The method comprises the steps of taking the sum of a deceleration area and a damping deceleration area as the sum of the maximum injection kinetic energy and an acceleration area as an equal area criterion for achieving transient synchronous critical stability of the grid-structured equipment, taking the injection of angular velocity step signals with different amplitude values as a target according to the moment and the position of kinetic energy injection, iteratively determining the maximum injection kinetic energy under the condition that the damping deceleration area passes the validity check, and taking the difference value between the maximum injection kinetic energy passing the validity check and the damping deceleration area passing the validity check as the transient synchronous stability margin of the grid-structured equipment. Preferably, a fault simulation model is built, a system is set to generate short-circuit faults, the faults are cut off after lasting for a period of time, fault cutting-off time is determined based on the fault simulation model, the fault cutting-off time and any time after fault cutting-off are used as kinetic energy injection time, and an electric angular velocity instruction generation port of a synchronous link of the network-structured equipment is used as a kinetic energy injection position. Preferably, the acceleration area is calculated as sh