Impedance compensation method for enabling forward-back substitution load flow calculation of three-phase four-wire system power distribution network to be converged

Abstract

The invention relates to an impedance compensation method for enabling forward-back substitution load flow calculation of a three-phase four-wire system power distribution network to be converged, and belongs to the technical field of power distribution network dispatching automation. The impedance compensation method solves the forward-back substitution load flow calculation convergence problem caused by too small neutral line grounding resistance, and the spectral radius of the jacobian matrix of fixed point iteration of the independent node voltage of the power distribution network in the power distribution network is utilized for judging the convergence of the load flow calculation. When the load flow calculation is not converged, a pair of opposite impedances is compensated between a neutral line grounding resistor and a grounding point through a spectrum in the power distribution network, after impedance compensation, a new node is added to the power distribution network, the newly-added node participates in the fixed point iteration of the independent node voltage of the power distribution network, the voltage of the newly-added node is obtained firstly, then the voltage of the newly-added node is utilized for solving the voltage of the neutral line node, therefore, the fixed point iteration is made to meet the condition of compressed mapping, and the convergence of the load flow calculation is achieved.

Description

technical field [0001] The invention relates to an impedance compensation method for making a three-phase four-wire distribution network forward and back to calculate a convergent power flow, and belongs to the technical field of distribution network dispatching automation. Background technique [0002] The low-voltage distribution network generally adopts a three-phase four-wire structure, and there are a large number of repeated grounding devices on the neutral line. Traditionally, the power flow calculation method of the three-phase three-wire system adopts the processing method of equivalently incorporating the neutral line parameters into the phase line parameters, and does not accurately consider the influence of the neutral line on the power flow calculation of the distribution network. Therefore, the existing three-phase three-wire system power flow calculation This method cannot perform accurate power flow calculation and analysis on the four-wire distribution netwo...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to propose an impedance compensation method to make the three-phase four-wire distribution network forward and back to calculate the convergence of power flow. By compensating a pair of opposite impedances between the neutral line grounding resistance and the grounding point, the forward Push back generation power flow calculation to meet the conditions of compressed mapping to solve the convergence problem of power flow calculation caused by too small neutral grounding resistance

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