Method for quickly positioning oscillating center of electric system

Abstract

The invention provides a method for quickly positioning the oscillating center of an electric system. In application aspects of inhibiting the oscillation of the system, coordinating the disconnection and the like, the accurate position of the oscillating center of the electric system often needs to be known. By the method, only the electric quantity and natural parameters of circuits need to be measured on the spot, the out-of-step oscillating center of the system can be accurately judged at the synchronous oscillation stage of the system, and the out-of-step quick disconnection criterion is realized based on the on-the-spot electric quantity. By the popularization and the application of the method for positioning the oscillating center based on the on-the-spot electric quantity, and the combination of the reliable quick disconnection criterion, the out-of-step disconnection control can be realized quickly, reliably and on the spot, and the method can also be adapted to different operating modes of the system, and realize the coordinating control of a plurality of disconnection devices.

Description

technical field [0001] The invention relates to the field of power system automation, in particular to a method for quickly locating the oscillation center of a power system. Background technique [0002] Improving the security and stability of the power system is the top priority of the power operation department. In the "Guidelines for Power System Safety and Stability" promulgated by our country, it stipulates three levels of safety and stability standards for the ability of my country's power grid to withstand large disturbances. When a serious failure cannot maintain synchronous and stable operation, it is necessary to prevent the system from crashing and minimize load loss. Disassembly is an important means of control to meet the above-mentioned third-level safety and stability standards and prevent the system from collapsing completely. [0003] Decoupling the oscillating system at the center section of the out-of-step oscillation can quickly calm the system oscillat...

AI Technical Summary

Problems solved by technology

The traditional oscillation separation device cannot determine the exact position of the oscillation center of the system. Usually, low voltage or impedance circle is used to determine whether the oscillation center is within the separation range. These criteria can only give an approximate range, and the out-of-step solution The column cannot provide better selectivity, so it cannot better adapt to the new requirements of the third line of defense of my country's interconnected grid

[0004] The traditional methods for locating the oscillation center include the impedance method, the minimum voltage divided by the current method, etc., each of which has its own shortcomings and cannot be well adapted to the requirements of my country's power grid.

The impedance method needs to be equivalent to the system, and the impedance is equal when viewed from the oscillation center to both sides. This method cannot adapt well to changes in the grid operation mode; the minimum voltage divided by current method is to divide the minimum voltage by current at the same time, but it needs The oscillation center of the system can only be judged after the system is out of step, and the judgment of the lowest voltage is affected by harmonics, which is not suitable for real-time running devices

Images