*2.1. Vehicle Model*

U.S. FTP-75 (EPA Federal Test Procedure) was employed in this model. The vehicle model estimated the required driving torque according to the vehicle speed from the driving cycles. The driving resistance forces included aerodynamic resistance, rolling resistance, and grading resistance.

The FTP-75 driving cycles include urban and highway sections. The total distance traveled in the urban cycle is 17.77 km, the total time is 1874 s, the average speed is 34.1 km/h, and the highest speed is 91.2 km/h, as shown in Figure 2. The total distance of the highway cycle is 16.5 km, the total time is 765 s, the average speed is 77.7 km/h, and the maximum speed is 96.4 km/h, as shown in Figure 3.

**Figure 2.** US EPA FTP75 urban driving cycle.

**Figure 3.** US EPA FTP75 highway driving cycle.
