The invention discloses a topology structure used for a multi-level T-shaped converter, which can achieve
rectifier conversion and is characterized in that the longitudinal axis of the T-shaped converter consists of 2k capacitors such as CT1, CT2, and to CTk-1, CTk, CB1, CB2, and to CBk-1 and CBk; the
transverse axis of the T-shaped converter consists of k bidirectional controllable switch such as S1, S2, and to Sk-1 and Sk; a
branch is arranged between nodes Di of Si and Si+1 (i is equal to 1, 2, and to k-1) and nodes DTi of CTi and CTi+1 (i is equal to 1, 2, and to k-1); a unidirectional
rectifier branch flowing from the
transverse axis to the longitudinal axis consists of STk1, STk2, and to STk2k; another
branch is arranged between the nodes Di, CBi>and CBi+1 (i is equal to 1, 2, and to k-1); the branch is a unidirectional
rectifier branch which flows from the longitudinal axis to the
transverse axis and consists of SBk1, SBk2, and to SBk2k, with the direction reverse to the previous branch; one end of the bidirectional controllable switch S1 is connected with the middle point of the longitudinal axis
capacitor. Number of levels can be increased by extending switch tubes, capacitors and rectifier branches; single-phase circuit combination can be applied to multi-phase systems. The topology structure can easily improve the number of levels of the converter and overcome the shortages that the
capacitor of the prior art has non-uniform
voltage and large quantity of devices.