The charging mode and charging voltage on uncontrolled charging stage of hybrid modular multilevel converter based on half-bridge sub-module and full-bridge sub-module are introduced. The problem of unsuccessfully self-taking energy by half-bridge sub-modules of the hybrid converter on the uncontrolled charging stage is analyzed. The three-stage charging strategies are proposed to solve the problem mentioned above

and the charging process is divided into three stages

which are called uncontrolled charging

half controlled charging mode 1 and 2. On the stage 1 of half controlled charging mode

all the full-bridge sub-modules are bypassed. On the stage 2 of half controlled charging mode

all the full-bridge sub-modules are partly blocked. The charging modes and charging voltages of half controlled charging mode 1 and mode 2 are analyzed. The three-stage charging strategies are verified by simulations. The theoretical analysis and simulation results show that the proposed three-stage charging strategies can solve the problem of unsuccessfully self-taking energy by half-bridge sub-modules of the hybrid converter.