State assessment method and terminal of AC/DC hybrid grid system

Abstract

The invention provides a state evaluation method and a terminal of an AC / DC hybrid grid system, which can model the AC / DC hybrid grid system model and measurement equations, and respectively model the measurement equations of the AC subsystem and the DC subsystem And model the pseudo-measurement equations of the observable VSC and non-observable VSC respectively; according to the established AC subsystem, DC subsystem and the measurement equations of the observable VSC and non-observable VSC, the AC-DC hybrid to be evaluated The power grid system is modeled with state variables and measurement equations to obtain the node voltage amplitude and phase angle of the AC subsystem, the voltage amplitude and phase angle of the AC side of the converter, and the node voltage amplitude of the DC subsystem. Condition assessment of AC / DC hybrid grid. The invention does not depend on the communication process between the measurement configuration and dispatching center and the VSC, has good practicability and tolerance, and can be extended to the state estimation of the three-phase unbalanced AC-DC distribution network in the future.

Description

technical field [0001] The present invention relates to the technical field of distribution network state evaluation, in particular to a state evaluation method and a terminal for an AC / DC hybrid power grid system. Background technique [0002] With the access of DC sources and loads and the development of flexible DC power electronic equipment, the AC-DC hybrid power grid with a variety of distributed generation (Distributed Generation, DG) is considered to be the mainstream architecture of the future distribution network. The operation brings more flexibility, but also exacerbates the difficulty of system state estimation and the lack of measurement data. [0003] The current mature AC state estimation does not take into account the characteristics of the DC system state quantity and quantity measurement and the uncertainty of various DG outputs, and usually assumes that the converter control method is known, and the pseudo-quantity when the converter control method is unk...

AI Technical Summary

Problems solved by technology

However, these two VSC models still assume that the converter control method is known, and no suggestions are made for the pseudo-measurement modeling when the converter control method is unknown

[0009] At present, there is no description or report of the similar technology of the present invention, and no similar data at home and abroad have been collected yet.

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