Method for estimating state of three-phase four-wire low-voltage distribution network

Abstract

The invention discloses a method for estimating the state of a three-phase four-wire low-voltage distribution network and belongs to the technical field of three-phase state estimation of distribution networks. The method comprises the following steps of firstly, by using a computer, inputting low-voltage distribution meter-reading electric data and a network structure which are acquired within any time section, and parameter information through a program, and initiating the data, the network structure and the parameter information; then calculating constant item parts of a node admittance matrix and a jacobian matrix; synthesizing a measuring equation and T-end point zero injection equation restriction, and taking a real part and an imaginary part of voltage as state variables to calculate unbalance amount, an index type weight function and the jacobian matrix; finally updating the state variables and performing astringency judgment to realize estimation on the state of the three-phase four-wire low-voltage distribution network. Active power and reactive power of a node can be independently calculated by the method, the adverse influence of bad data on an estimating result is prevented, and the method has the characteristics of high difference resistance, good astringency, good numerical stability and the like. The method is widely applied to the estimation on the state of the three-phase four-wire low-voltage distribution network.

Description

technical field [0001] The invention belongs to the technical field of three-phase state estimation of a distribution network, and in particular relates to a method for state estimation of a three-phase four-wire low-voltage distribution network. Background technique [0002] With the development of the economy and the improvement of people's living standards, the power users of the low-voltage distribution network have put forward higher and higher requirements for the quality of power supply, so it is particularly important to strengthen the operation monitoring and control of the low-voltage distribution network. State estimation is an important part of the energy management system. Its results directly affect the intelligent analysis and decision-making of power grid dispatching, and provide reliable and complete system operation status information for the power distribution management system. It is the source of data for power distribution system analysis. It plays an i...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a state estimation method for a three-phase four-wire low-voltage distribution network in view of the shortcomings of existing distribution network state estimation methods. By making full use of measured values ​​and rationally allocating weights, the method has Strong tolerance, good convergence, convergence speed, and online application prospects, etc., and do not require power measurements to appear in pairs and the weight coefficients of P and Q measurements are the same

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