Traction Control for Electric Vehicles With Dual-Mode Coupling Drive System on Split Ramps

The total driving force available for electric vehicles (EVs) on split ramps will be limited by the ground adhesion conditions, causing insufficient traffic ability and bad handling stability. This article proposes a traction control system (TCS) to address these issues. The TCS is built with conditional integral-error sliding mode control (CSMC) and a dual-mode coupling drive system (DMCDS), which simplifies the control structure, increases the controller's uncertainty for system parameters and models, and improves dynamics performance. The designed CSMC retains the benefits of conditional integral sliding mode control (CISMC) in terms of error elimination and chattering within the boundary layer while also predicting error change trends and improving control stability outside of the boundary layer. The stability and robustness of TCS are analyzed and proven. In terms of dynamics performance improvement, DMCDS has a coupled drive (COU) mode that can transfer the motor power on the low-adhesion side to the wheel on the high-adhesion road, effectively improving the dynamics. The simulation and real vehicle test results show that the TCS has a better control effect than other TCS and significantly improves dynamics performance compared to EVs with distributed drive (DIS). The improvement effect of dynamics grows as the slope increases.