Extensible modeling and analysis method for low-voltage AC/DC system in peer-to-peer control mode

Abstract

The invention relates to an extensible modeling and analysis method for a low-voltage AC / DC system in a peer-to-peer control mode. The method comprises the following steps: 1, constructing a state matrix and an input matrix of a single station; establishing a state space model of each station according to a droop control strategy, and forming a state matrix and an input matrix of each station; 2, constructing an overall state matrix and an input matrix of all converter stations; splicing the single-station state matrix and the input matrix, and integrating to form an overall state matrix and an input matrix of the N converter stations; 3, constructing a DC network matrix, establishing a model of an N-end DC network according to the Kirchhoff voltage theorem and the Kirchhoff current theorem, and integrating to form the DC network matrix; 4, constructing an overall state space matrix of the system, and carrying out modular splicing on the overall state matrix of the N converter stations, the input matrix and the DC network matrix to obtain a complete state space matrix of the N-terminal DC system; and 5, carrying out eigenvalue analysis on the complete state space matrix, and researching a system operation mechanism.

Description

technical field [0001] The invention relates to the field of electric power, in particular to a scalable modeling and analysis method for a low-voltage AC / DC system under a peer-to-peer control mode. Background technique [0002] Distributed energy has become the core of my country's energy transformation work due to its advantages of strong complementarity and nearby consumption. Although the current distribution network in my country is still dominated by AC, the DC connection of distributed energy such as wind power and photovoltaics to the grid can reduce commutation links, improve efficiency, and reduce harmonic content; DC loads such as electric vehicle charging piles and storage The above factors have greatly promoted the development of DC power distribution. [0003] figure 1 Describes an equivalent circuit of a low-voltage multi-terminal AC-DC power distribution system, in which AC system 1, AC system 2...AC system n...AC system N, etc. are interconnected through t...

AI Technical Summary

Problems solved by technology

In addition, droop control is the main coordinated control method of the multi-terminal DC system. Although the power sharing between the stations is realized under the condition of low communication requirements, the stability control effect on the DC voltage is sacrificed to a certain extent, and the system stability The problem is more prominent

Aiming at the above problems, many scholars have carried out a series of studies, but they mainly focus on single-bus system or double-terminal system, while the generalized stability analysis method for low-voltage multi-terminal DC system structure is rarely mentioned, and how to effectively reduce the high There are still technical gaps in the complexity of high-level low-voltage multi-terminal DC systems

Images