Estimation and Control Methods for Active Reduction of Engine-Induced Torsional Vibration in Hybrid Powertrains

The objective of this work is the development of estimation and control methods for the active reduction of engine-induced torsional oscillations in automotive powertrains. The dynamic engine torque is estimated using Unknown Input Observer (UIO) techniques. The filtering of the mean value and harmonic components of the dynamic torque is performed using a Linear Parameter Variant (LPV) estimator. The characteristics of the torsional system are identified using Errors-In-Variables (EIV) setup in closed-loop operation. Before the development of the controller, a methodology to analyze the potential available for active vibration reduction is formulated. Further, a modular architecture is presented to enable the integration of the controller irrespective of their realization. To characterize the losses associated with the active vibration reduction control, a harmonic characterization of the actuation unit efficiency is formulated. The control development begins with an abstract definition of the active vibration reduction problem, which is used to synthesize control methodologies such as adaptive, robust and time-delayed control. The generic nature of the developed controllers facilitates their application beyond active vibration reduction in hybrid powertrains. The developed controllers are analyzed with simulations and validated using the experimental setup, demonstrating the desired torsional vibration reduction.