Detecting bifurcation types in DC-DC switching converters by duplicate symbolic sequence

The main switching block is presented to distinguish the switching behaviors and the degree of the converter´s complexity during one switching period. By adopting the coarse-grained symbolic sequence method, the secondary switching block and secondary symbolic sequence are established in terms of main switching block too. Hence the duplicate symbolic sequence is put forward to detect bifurcation types in DC-DC switching converters. A voltage-mode-controlled flyback converter is used as an example to illustrate the applications of the duplicate symbolic sequence.