A voltage sag random prediction method based on actual power network monitoring information

Abstract

The invention discloses a voltage sag random prediction method based on actual power network monitoring information, belonging to the technical field of power quality analysis. The method comprises the following steps of: reading actual power network parameters to obtain node admittance matrix; processing the measured sag data of each node and obtaining the probabilistic model of fault type and fault duration; establishing a system fault information model; generating fault information by Latin hypercube sampling, and forming the original database of fault information; carrying out fault simulation to calculate the error between the predicted result and the measured result. According to whether the error meets the requirement, the fault information model is corrected until the error meets the requirement or reaches the preset correction times, and the final predicted result is obtained. The present invention can effectively avoid the problems of poor stability, slow convergence, long time consuming, large error of prediction result and the like in the existing prediction method, and the prediction result is more accurate.

Description

technical field [0001] The invention belongs to the technical field of power quality analysis, and in particular relates to a method for randomly predicting voltage sags based on actual power grid monitoring information. Background technique [0002] With the wide application of sensitive equipment such as power electronics in the power grid, voltage sag has become one of the most important power quality problems. Typical sensitive equipment, such as computers, AC speed controllers, AC contactors, etc., may cause problems such as equipment stoppage, unstable operation or errors, efficiency reduction or life shortening after being subjected to voltage sag disturbances, which in turn will reduce the output of industrial production lines. And quality degradation or even complete interruption of production process or service activities, resulting in huge economic losses. For this reason, it is of great significance to estimate the occurrence of voltage sags in the power grid, f...

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Problems solved by technology

However, the Monte Carlo method has the disadvantages of poor stability, slow convergence, and long time

In addition, with the widespread application of the power quality online monitoring system in various regions of my country, monitoring devices have been installed in some nodes in the actual system, which can obtain enough sag events. The random prediction method of voltage sags can not only overcome the defects of poor stability, slow convergence and long time of Monte Carlo method, but also make the prediction results more realistic, provide power grid companies and users with sag information, and find weak power grids link, take countermeasures in advance to alleviate voltage sags and reduce economic losses

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