Patent ID: 11909214
Assignee: SOUTHEAST UNIVERSITY
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 0:
1. A topology of a series-connected MMC converter with a small number of modules, wherein the topology is composed of a three-phase bridge circuit, half-bridge valve strings, a three-phase filter inductor, and a three-phase grid frequency transformer;
the three-phase bridge circuit is formed by series connection of a phase-A bridge circuit, a phase-B bridge circuit, and a phase-C bridge circuit, any of which is formed by combination of a high-voltage DC capacitor, a first high-voltage switch string, and a second high-voltage switch string;
and the first high-voltage switch string and the second high-voltage switch string are connected in series and then connected in parallel to the high-voltage DC capacitor;
the half-bridge valve string is formed by series connection of a set of half-bridge submodules, full-bridge submodules, or half-bridge/full-bridge hybrid submodules; and
the other terminals of the three-phase filter inductor are respectively connected to primary winding terminals of the three-phase grid frequency transformer, and secondary winding terminals of the three-phase grid frequency transformer form a high-voltage AC port; and a connection manner of the three-phase grid frequency transformer is one of Y/Y, Δ/Y, Δ/Δ, and Y/Δ structures.