Based on equations of motion of 2K-H planetary gear trains, given a determine method of self locking of hydrodynamic power split torque converter (HSTC); Put forward an analysis method of power flow of HSTC; and established the relationships between structural parameters and transmission parameters of HSTC; The transmission parameters of all kinds of HSTC such as power flow, torque ratio, power split ratio and efficiency are compared. The results of research show: if HSTC have no power circulation and self-locking, the efficiency of HSTC is higher than hydraulic torque converter, and applications of HSTC are wider than hydraulic torque converter. The study results can provide a theoretical basis for calculation and design of HSTC.
