Energy Recovered in Exhaust Gases on Diesel Engine, Oriented to a Hybrid Drivetrain

Abstract

In recent years, various technologies have been developed for hybrid vehicles, ranging from energy management to the type of engines used, where Diesel engines have been used with the aim to improve fuel efficiency. This work presents a novel scheme for energy recovery from the exhaust gases of a turbocharged diesel engine integrated into a hybrid powertrain. The operation is explained through simulations conducted in MATLAB, using a fifth-order dynamic model where the dynamics of the compressor and turbine are not coupled and for which a feedback linearized controller is designed. Simulation results confirm the presence of excess energy in the exhaust gases. To demonstrate this, an engine velocity profile is simulated and the available o required power in both input and output manifolds is determined. The integral of the difference between these two powers clearly identifies an energy excess that can be converted to electric energy to be used in the propulsion system. This decoupling of the compressor and turbine is crucial as in conventional turbochargers they are mechanically coupled. The implementation of this schemes requires to couple to the shaft of the turbocompresor a high speed electrical engine that absorbs the available energy excess. Finally, the achieved recovery ranges from 1-3%, which demonstrates the effectiveness of the proposal.

Keywords

• Hybrid propulsion train
• diesel engine control
• feedback linearized control
• mathematical model
• turbocharger