Robust Oscillation Suppression Control of Electrified Powertrain System Considering Mechanical-Electric-Network Effects

Abstract

This paper works on the oscillation of electrified powertrain system in an integrated manner where combined mechanical-electric-network effects are all taking into consideration, and a robust oscillation controller is proposed to suppress the effects-caused oscillation and to maintain the system stability. An integrated model is developed in which driving motor, drivetrain and communication network are all included. Thus, torque ripples in the driving motor, nonlinear gear backlash as well as driveshaft flexibility in the drivetrain and network-induced delays that may cause powertrain system oscillation can be all considered. In order to dealing with the coupling effects of network-induced delays and event-driven manner of the controller nodes, a delay-free discrete model is further built via polytopic inclusion approach and system augmentation technique. An energy-to-peak performance based robust controller is proposed to ensure the torsional oscillation damping as well as vehicle speed tracking performance. During backlash mode, as the driving motor and the load are decoupled, a sliding mode compensator is further adopted to restrain the torsional oscillation. The stability of electrified powertrain control system is ensured by using Lyapunov theory, and the controller gain is obtained by solving a set of linear matrix inequalities (LMIs). Comparative simulation tests are carried out by using Matlab/Simulink in which a delicate controller area network (CAN) model is developed via SimEvent. The combined mechanical-electric-networked effects on torsional oscillation are demonstrated during the simulation tests, while the performance of the proposed controller is well verified.

Keywords

• Electrified powertrain
• nonlinear gear backlash
• network-induced delays
• robust energy-to-peak controller
• sliding mode compensator