双电机耦合驱动系统构型分层设计方法

The dual-motor coupling drive system can realize mode shifting without power interruption and efficiently driving under different loads,which significantly improves the power performance and energy economy of pure electric vehicles. Due to its characteristics of multi-degree-of-freedom and multi-power-source drive,the configuration design has no regularities to follow. In this paper,the function analysis method is used to study the process of function generation and structure derivation of the dual-motor coupling drive system configuration,and a hierarchical design method including function generation and structure derivation is proposed. A graph theory model with sub-mechanism as the basic unit is established;the path coupling conditions are determined based on motion interference. Through path superimposition,the shift sequences that meet functional requirements are obtained. A stepwise structure derivation method from basic configuration to gear-shaft configuration and gear-shaft configuration to concrete configuration is proposed. Finally,taking an electric commercial vehicle as an example,the optimal scheme is selected for parameters design and simulation analysis. Compared with the original vehicle,the power consumption for 100 km of this scheme is reduced by 8.97% in C-WTVC working condition,and the acceleration time from 0-50 km/h is shortened by 8.9 s.