Configuration Design and Performance Analysis of a Three‐Power Source Power Transmission System Based on Lever Method

This paper proposes a supplementary design method for a three‐power source hybrid power transmission system based on the lever method, aimed at enhancing its power performance and economic efficiency. It makes up for some defects of traditional configuration design methods. Firstly, in order to better show the connection between the two planetary rows in the composite distribution configuration, an equivalent lever model with four nodes was established. The rod model was screened based on the connection relationship between the mechanical point distribution and power source. The rod model was analyzed in combination with the motor speed and torque characteristics, and the value interval of the two mechanical points of the composite distribution rod model was obtained. Then, the four‐node rod model was split. By adding the clutch and brake to control the connection between different nodes of the planetary bank, the working mode of the configuration can be switched. The supplementary design was carried out by increasing the input distribution to compensate for the low efficiency of the composite distribution configuration when driving at low speed, and three optimal configurations were obtained. (Based on the constraints of factors such as rod length, there are finally three solutions that meet the requirements.) Finally, the vehicle dynamics model was established, and the simulation results based on the dynamic programming principle showed that compared with the typical three‐power configuration Prius+, the fuel economy of the optimal configuration was improved in different degrees. Configuration (II) was selected as the object for parameter optimization, and the results showed that the power performance of the vehicle is improved by 1.8%, and the economy is improved by 5.47%, which verifies the validity of the configuration design method proposed in this paper.