Bipolar bi-directional DC converter and its control method and control device

摘要

In the present application, a bipolar bi-directional DC converter and a control method and a control device thereof are provided. The bipolar bidirectional DC converter includes at least two valve group strings and at least six magnetic elements, and is divided into an I type valve group string and a II type valve group string by the connection relationship between the valve group string and the low voltage side port of the bidirectional DC converter. ; The positive pole of the low voltage DC port of the I-type valve group string constitutes the positive pole of the low voltage side port of the positive bidirectional DC converter; The positive pole of the low voltage DC port of the type II valve group string is connected to the negative pole of the low voltage DC port of the type I valve group string, and forms the neutral point of the low voltage side port of the positive bidirectional DC converter, and the low voltage DC port of the type II valve group string. The cathode of the bipolar bidirectional DC converter constitutes the cathode of the low voltage side port; Each valve group string includes a high voltage DC port, a low voltage DC port, and at least three AC ports, each AC port connected to one magnetic element; The other end of the magnetic element to which all the AC ports in the same valve group string are connected is connected.