Identifying method of distribution parameters of transmission line

Abstract

The invention relates to an identifying method of distribution parameter of a transmission line. The method comprises the following steps: calculating a positive-sequence component and a zero-sequence component for a transmission line with external faults by collecting electric signal momentary values at the head and tail ends; and calculating positive-sequence distribution parameters: a resistor R1, an inducer L1 and a capacitor C1; then, calculating zero-sequence distribution parameters: a resistor R0, an inducer L0 and a capacitor C0. According to the invention, the line distribution parameters can be solved just by collecting voltage and current synchronous momentary values at both ends without the necessity to master parameters on both sides and operational states of other parts. The identifying precision of the method is not affected by fault condition, and the method has the advantages of simpleness and convenience in operation, and accurate calculation, and provides accurate line parameters for the power grid so as to ensure the reliability of calculation results of subsequent power system calculation such as state estimation, load flow calculation, fault location, and protection relay setting.

Description

technical field [0001] The invention relates to a method for identifying parameters of transmission lines, in particular to a method for identifying distribution parameters of transmission lines based on fault data. Background technique [0002] With the rapid development of my country's power grid construction, the scale of the power grid is gradually expanding, with wider distribution, more components, and more complex network structure. The stable and safe operation of the power grid is facing severe challenges. Accurate power grid model parameters are an important basis for power system calculations such as state estimation, power flow calculation, fault location, and relay protection setting. Improving its accuracy is of great significance to the safe operation of lines and systems. However, due to the influence of various factors such as terrain and climate, the line parameters will change, and the line parameters held by the power department are often inaccurate. Ther...

AI Technical Summary

Problems solved by technology

[0003] At present, there are two main methods for online parameter identification of lines. One is the parameter identification method based on steady-state data. This method is based on the online actual measurement of the monitoring and data acquisition system (SCADA) and the phasor acquisition unit (PMU) at both ends of the line. Data estimation of line parameters mainly includes augmented state estimation method, residual sensitivity analysis method, etc. These methods involve many parameters and measurements, and various errors are easy to interact with each other, and the zero-sequence parameters of the line cannot be identified

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