A Mechanical-Hardware-in-the-Loop Test Bench for Verification of Multimotor Drivetrain Systems

Multimotor drivetrain systems utilizing more than one electric machine for propulsion can provide possibilities to improve energy efficiency and vehicle dynamic performance of battery electric vehicles (BEVs). However, laboratory testing of such drivetrain systems using a dyno test bench can be costly. A solution can be to use a mechanical-hardware-in-the-loop (MHIL) test bench, which combines real-time simulations of the intended working environment with the dyno test bench. To utilize the MHIL approach for multimotor drivetrain systems, one drivetrain is implemented in the dyno test bench, while the remaining are simulated using a real-time simulator, therefore, providing a less expensive solution for laboratory testing of drivetrain components and control methods in their intended environment. In this work, an MHIL test bench for a multimotor drivetrain system is designed and experimentally verified. A BEV with two independently driven front wheels is considered for modeling. To interface the dyno test bench with real-time simulation, two different methods, namely, open loop and closed loop, are proposed and verified in experiments by prototyping an MHIL test bench. In addition, an anti-slip control is implemented and evaluated experimentally to demonstrate the suitability of the proposed MHIL test bench in the verification of control methods.