A Novel Method to Actively Damp the Vibration of the Hybrid Powertrain by Utilizing a Flywheel Integrated-Starter-Generator

Abstract

In this paper, a novel method to actively damp the powertrain vibration by utilizing a flywheel integrated starter generator (FISG) is proposed and validated on the testbench. A more light-weighted, economical, and compact hybrid powertrain devoid of clutches or dampers is built by replacing its flywheel with the ISG rotor. Motor torque having the opposite phase of the engine torque is applied to reduce the vibration. As opposed to the passive methods, which usually make use of the inertial and/or the damping properties of the components to absorb the vibration, this active approach is defined as active damping. Firstly, active damping is proved to be theoretically feasible by simulation based on an engine torque observer. To get the practical-application-oriented motor torque waveform, the observer torque is then processed by considering some realistic factors, such as the motor's response delay and the torque demand limit at MCU (Motor Control Unit), and is finally simplified as the rectangular waveform by off-line simulation. Secondly, an algorithm operating on the original resolver aimed at calculating the real-time crank position is proposed and programmed directly in the MCU. Finally, active damping is realized online utilizing a feedforward method by programming the crank-torque table in MCU. Experiments in both stable and transient conditions are conducted. Results show that active damping can attenuate the vibration effectively, especially over low speed and load ranges. The speed fluctuation range and the cyclic squared angular acceleration can be reduced by 79.7% and 89.7% respectively at 700 rpm when cranking. The crank vibration in transient conditions, including dragging and free deceleration, can also be suppressed, showing potential to realize fast and quiet engine start and halt.INDEX TERMS Active damping, crank position calculation, engine torque cancellation, flywheel ISG, hybrid powertrain.

Efficient Tuning Scheme of Mode-Switching-Based Powertrain Oscillation Controller Considering Nonlinear Backlash

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“…Vibration suppression is also one of the indispensable key technologies for automotive powertrains [9], [10]. When an abrupt change occurs in a driving torque, transient vibrations are caused in an automotive driveline, significantly providing adverse influences for the comfortability and lifetime of the parts.…”

Steady-state and start-up transient responses of a belt-driven starter generator system for micro-hybrid electric vehicles

“…The world is setting off an upsurge of new energy, accompanied by the wave of reducing traditional energy consumption and reducing environmental pollution. In this wave, hybrid electric vehicle (HEV) has a great development and becomes a research focus of many universities and automobile enterprises because of the advantages of low pollution and low fuel consumption (Chen et al, 2020; Hu et al, 2020; Itagaki et al, 2002; Olatunde, 2008; Tamai et al, 2006).…”

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