A review on Hybrid Electric Vehicle and simulation on Hybrid Electric Vehicle Drivetrain Abstract

Figure 5. Power Curve of Engine and Battery (Motor)
The Figure 5 above shows battery/motor and engine power Vs time, as we know for acceleration the electric motor is only used and engine is to maintain the vehicle speed, so when the acceleration starts the motor starts powering at 20s so it as in figure the motor power is increasing and the engine power has slight changes. The motor decreases after the 140s second because vehicle starts to deaccelerate. Negative curve after the motor stops, in the figure it shows the power that is absorbed by the motor to charge some amount of battery from the rotating engine shaft and some amount of power is gained due to regenerative braking.


Figure 6. Battery Charge curve Figure 7. Battery Electrical losses

The figure 6 above shows the battery charge usage and battery losses is shown by the figure 7 above. Figure 6 above shows the battery charge used by the electric motor during the whole process as the acceleration increase the battery charge usage also increases and it used until the deacceleration of the vehicle and then it decreases. The figure 7 above shows battery losses due various reasons, it increases during the acceleration due more current flow and decreases during deacceleration.

5. Conclusion

The simulation of a parallel Hybrid electric powertrain was completed. The method of the simulation was that the engine was powering the wheels to maintain a speed and the vehicle was accelerated and deaccelerate by electric motor, engine was not used to accelerate or deaccelerate. The electric motor was commanded by a speed command strategy and speed controller. The engine was having a constant power due constant throttle. And the power and speed of both engine and motor were determined for 200s step time. The power curves showed that the vehicle has the electrical power which is higher than the engine power and it proves that the vehicle can also accelerate at high speed with only the electric motor. The electric motor also uses the regenerative brake to absorbs some of the power to recharge the battery. And the charging level of battery was also measured with respect to time it also shows that the battery. The charge level also decreases with the time due to increase in motor power and the it also gains some power during the deacceleration due regenerative braking.
The vehicle velocity also increases and decreases as per the figures discussed above with respect to the electric motor acceleration and deacceleration respectively, which shows the output of the simulation as speed of the vehicle. The simulation shows that the vehicle can run on electric motor independently for performance requirement in parallel mode of Hybrid Electric Vehicle powertrain. According to studied research [3],[4],[5], it can be concluded that Parallel Hybrid electric vehicle improves the fuel economy as well as engine efficiency in standard driving cycle as well as real world driving cycle. The improvement in engine efficiency also increased the life span of the engine. Therefore, from all the about research and simulation done it can be stated that the Parallel Hybrid electric vehicle or Hybrid Electric Vehicle has very promising potential solution for improvement of fuel economy than the ICEV conventional vehicles.

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