Control method for dc/dc converter and dc/dc converter

A DC/DC converter, comprising:

• a primary side circuit comprising a primary side switch which is driven by a primary side driving signal;
• a secondary side circuit, electrically isolated with the primary side circuit, comprising a first secondary side bridge arm consisting of a fifth switch and a sixth switch in series, and a second secondary side bridge arm consisting of a seventh switch and an eighth switch in series, wherein the first secondary side bridge arm is parallel to the second secondary side bridge arm;
• and
• a control apparatus comprising:
• a primary side control module, configured to provide the primary side driving signal to drive one or more primary side switches of the primary side circuit;
• a signal providing module, configured to provide a sixth signal, a fifth signal, a seventh signal and an eighth signal, wherein a phase shift angle exists between the sixth signal and the primary side driving signal;
• the sixth signal, the fifth signal, the seventh signal and the eighth signal in turn have a predetermined phase difference;
• and the switching frequency of the sixth signal, the fifth signal, the seventh signal or the eighth signal is half of the switching frequency of the primary side driving signal;
• and
• a secondary side control module, configured to generate secondary side driving signals to drive the sixth switch, the fifth switch, the seventh switch and the eighth switch according to the sixth signal, the fifth signal, the seventh signal and the eighth signal.