CURRENT CONVERTER MODULE UNIT, CURRENT CONVERTER, DIRECT-CURRENT TRANSMISSION SYSTEM AND CONTROL METHOD

摘要

A current converter module unit, a converter, a direct-current transmission system and a control method. In the converter module unit, the positive electrode of a first switch module (T1, D1) is connected to the positive electrode of a first energy storage element (C1), and the negative electrode of a second switch module (T2, D2) is connected to the negative electrode of the first energy storage element; the negative electrode of a diode (D6) is connected to the positive electrode of the first switch module, the positive electrode of the diode is respectively connected to the negative electrode of a second energy storage element (C2) and the negative electrode of a fourth switch module (T4, D4), the positive electrode of the fourth switch module is connected to the negative electrode of a third switch module (T3, D3), and the positive electrode of the second energy storage element is connected to the positive electrode of the third switch module; and the positive electrode of the third switch module is connected to the positive electrode of a fifth switch module (T5, D5), and the negative electrode of the fifth switch module is connected to the negative electrode of the second switch module. This structure can provide a favourable direct-current side fault ride-through performance, thereby overcoming the limitation and deficiency of structures such as a full-bridge module and a clamping double-module, and having better economical and technological performances.