A Method for State Estimation of Power System

Abstract

The invention belongs to the technical field of electric system operation and control, and particularly relates to an electric system state estimation method of a Phasor Measurement Unit-PMU based on an interpolation matrix. According to the method, during the updating interval period of SCADA measurement, a state, obtained through a PMU interpolation, of an area U is equivalent to prior state information of the area U, the prior state information is continuously updated at each sampling instant of the PMU, the interpolation matrix is updated when SCADA measurement and PMU measurement reach simultaneously at the next moment, and therefore the real-time running state of each node of the area U is worked out. The method has the advantages of being high in accuracy and sampling speed of PMU measurement, and can track the running state of the system accurately in real time.

Description

technical field [0001] The invention belongs to the technical field of power system operation and control, and in particular relates to a power system state estimation method based on an interpolation matrix and including a phase angle measurement device (PhasorMeasurementUnit-PMU). Background technique [0002] Since Schweppe introduced the state estimation into the power system for the first time in 1970, the state estimation of the power system has become an important part of the grid energy management system and the online decision-making stability control system. Injection measurement, active and reactive power flow measurement, voltage and current measurement) to obtain the best estimate of the current state of the system, and provide real-time and accurate operating data for the online analysis and control of the power system. At present, these telemetry data for power system state estimation mainly come from SCADA (Data Acquisition and Supervisory Control System), an...

AI Technical Summary

Problems solved by technology

[0004] When a short circuit occurs in the system (three-phase or single-phase ground short circuit, etc.), these algorithms cannot effectively track the transient changes of the voltage or phase angle of each node in the system, especially the voltage or phase angle of the nodes that cannot be directly observed by the PMU. Transient change of phase angle;

[0005] When the system experiences large disturbances (short circuit, load mutation or line parameter error), the robustness of the algorithm is poor, and even the algorithm does not converge;

[0006] The distribution of measurement weights in the algorithm is given according to experience, which cannot reflect the change of measurement error in the dynamic situation of the system, resulting in unreasonable weight distribution and affecting the accuracy of estimation;

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