Area information based quiescent voltage unstability prediction method

Abstract

The invention belongs to the field of a power supply system and automatics thereof and is applicable to wide area information based quiescent voltage unstability prediction of power grid real-time states and working conditions after a predicted accident. The method comprises the steps of: (1) integrating the PMU (Power Management Unit) node distribution information and actual grid structure of the power grid and dividing the power grid into a plurality of generating areas and load areas; (2) carrying out P-V curve computation on the basis of SCADA (Supervisory Control And Data Acquisition) measurement information and state estimation results to obtain critical voltage of each node at the moment of voltage breakdown; (3) carrying out Q-V model analysis computation on a trend the voltage ofwhich is close to breakdown to obtain all participation factors installed with PMU nodes; (4) weighting the voltage margin of each node in real time to be used as a compressive voltage margin index according to real voltage data detected by a PMU by taking the PMU node participation factors as weight; and (5) when the compressive voltage margin index is relatively small, using the sensitivity of the reactive power loss change of a receiving section in a load area to transmission active power as a real-time proof for calculating voltage unstability.

Description

technical field [0001] The invention belongs to the technical field of electric power systems and automation thereof. More precisely, the invention relates to a method for predicting static voltage instability based on wide-area information. Background technique [0002] In recent years, with the continuous expansion of the grid scale, the continuous increase of load and the gradual marketization of electricity, the operating point of the power system is getting closer and closer to the limit of stability, and the risk of voltage instability or even voltage collapse in the entire system is increasing, especially When the power supply is far away from the load center or the transmission system is heavily loaded, when the reactive power supply is cut off suddenly, or the reactive power supply is insufficient, and the load continues to increase to a certain extent, the voltage may drop sharply, causing Voltage collapse problem. [0003] Although currently in the power grid dis...

AI Technical Summary

Problems solved by technology

However, the least squares fitting method is not suitable for large-scale and highly nonlinear large-scale power grids. The large-scale power system is a time-varying nonlinear system, and it is difficult to use the local monitoring value of the PMU to predict the voltage instability state.

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