A GT-SUITE/Simulink simulation platform was established and tuned for a 6.7 L diesel engine equipped with electrically assisted turbocharger (eTurbo) to study how to regulate electric power for the eTurbo to achieve electric energy balance and optimum engine equivalent thermal efficiency on the basis of keeping engine dynamic performance unchanged. First

based on the simulation platform

the interaction between eTurbo power and engine thermal efficiency at steady state condition was studied

and the engine equivalent thermal efficiency was evaluated at all operating conditions. Then

a simulation was conducted with FTP-75 and US06 driving cycles. The results indicate as follows: with the increase of assistant energy

engine thermal efficiency increases by up to 2.95% in the FTP-75 cycle and by up to 1.08% in the US06 cycle

while the regenerated energy keeps decreasing by up to 93.1% in electricity deficit. In the FTP-75 cycle

additional energy

such as one recovered from braking

should be provided for an eTurbo engine to save fuel.Compared with the FTP-75 cycle

more energy can be recovered in the US06 cycle due to higher load

thus achieving an electric energy balance.