Graph theory analysis method for common mode current path of photovoltaic grid-connected inverter

Abstract

The invention discloses a graph-theory analysis method for common-mode current paths of photovoltaic grid-connected inverters. The graph-theory analysis method comprises the following steps: Step 1, drawing a network node graph of the photovoltaic grid-connected inverters according to a common-mode current topology circuit of the photovoltaic grid-connected inverters, wherein the network node graph of the photovoltaic grid-connected inverters refers to binary node connection relationship consisting of nodes and directed edges; Step 2, establishing an n*n matrix model A according to the binary node connection relationship; Step 3, performing calculation so as to obtain a current-path function delta; Step 4, eliminating illegal paths in the current-path function delta so as to obtain a current-path function delta' without redundant paths; Step 5, obtaining a common-mode current-path function (referring to the Specification) according to the current-path function delta' without redundant paths; Step 6, judging the switching states of the common-mode current paths according to the common-mode current-path function (referring to the Specification). The graph-theory analysis method disclosed by the invention contributes to guiding the common-mode current inhibition of the photovoltaic grid-connected inverters and generating new topological structures.

Description

technical field [0001] The invention relates to the analysis of the topological structure of a power electronic converter, and proposes a graph theory analysis method for a common-mode current path of a photovoltaic grid-connected inverter, belonging to the technical fields of power electronic conversion technology and solar power generation. Background technique [0002] Power electronic converters are widely used in industrial automation and power conversion occasions, from two-level converters suitable for low and medium voltages to three-level or even multi-level converters suitable for medium and high voltages. With the increasing number of energy storage components, the working mode of circuit topology is also increasing, which brings huge resistance to the research and design of power electronic topology. Graph Theory is a mathematical tool for studying graphs. As long as the system contains binary relations, it can be analyzed by graph theory. At present, graph theo...

AI Technical Summary

Problems solved by technology

Traditional power electronic converter common-mode current suppression methods mostly rely on inspiration and experimentation, without a theoretical analysis method as a guide

Images