A novel dual-layer cascaded torque control mechanism for the improved drivetrain performance for electric vehicles

In recent years, due to low carbon emissions, demand for electric vehicles (EVs) has increased notably. To potentially compete with the internal combustion engine-based modern utility vehicle in the market share, enhancement in the acceleration profile and the cruise control must be assured from the manufacturers of EVs. This research paper highlights the importance of precise regulation of electromagnetic torque in the drivetrain for achieving desirable acceleration profiles and vehicle dynamics. However, the presence of nonlinearities makes real-time computation of optimal drivetrain torque a challenging task, and conventional deterministic approaches have limitations. To address this issue, the paper proposes a novel dual-layer cascaded control (DLCC) mechanism. An auxiliary control loop has been designed and superimposed with the primary and secondary control loop of the propulsion unit to compensate the incomprehensible stray losses. The performance of the proposed control mechanism was first evaluated using the dSPACE DS1103 system (driven by PowerPC microprocessor) and a Delfino microcontroller in a Hardware-in-Loop setup facilitated with an eddy current braking test bench system. Finally, the performance and the feasibility of the proposed mechanism have been evaluated for the real-world driving dynamics by developing an ARM Cortex A-72 processor driven prototype model. The improvement ensured through the proposed DLCC technique is approximately 1.5% and 12.5% in acceleration and cruising ability, respectively.