This project implements a control algorithm for traction and braking, applicable to electric vehicles such as cars, buses, and trains.
The controller is based on longitudinal dynamics evaluating speed, acceleration, power, and torque over a given route.
In addition, the framework allows the estimation of energy consumption and approximate CO₂ emissions (depending on the energy source), providing insights into the environmental impact of different control strategies.
Efficient traction and braking control is essential for modern mobility systems.
This project provides a simple yet effective approach to:
- Control vehicle acceleration and deceleration.
- Analyze dynamic performance (velocity, acceleration, power, torque).
- Estimate energy demand during a trip.
- Approximate CO₂ emissions, useful for comparing scenarios.
The project can be extended to different transport modes (passenger cars, heavy vehicles, or rail systems).
A real-world case study was carried out for a bus route between Dallas Fort Worth International Airport (Terminal E) and AT&T Stadium.
The Yutong IC15E was selected for the route operation. It proved a capable operational characteristics. Specially, reaching and maintaining >100 km/h, ideal for U.S. highways.
A set of key performance indicators (KPIs) was selected to evaluate the bus's performance along its designated route. The Table shows the results of a single trip from Terminal E at Dallas Fort Worth International Airport to Dallas AT&T Stadium. For this evaluation, the bus operated at 85% of its maximum load capacity; in addition, stops at traffic lights were considered.
| KPI | Value |
|---|---|
| Total Distance Travelled | 21.93 km |
| Trip Moving Time | 21m 41s |
| Total Trip Time (incl. stops) | ~34m 11s |
| Max Speed | 104.3 km/h |
| Average Speed | 58.3 km/h |
| Max Acceleration | 1.09 m/s² |
| Max Deceleration | 0.90 m/s² |
| Total Energy Required (traction) | 107.5 MJ |
| Recovered Energy (regen braking) | 35.5 MJ |
| Net Energy Consumption (w/ aux) | 131.1 MJ (40.5 kWh) |
In the bus simulation, the vehicle reached a maximum speed of ~105 km/h with an average of ~58 km/h, closely following the reference speed profile and adapting well to local speed restrictions. Acceleration remained within comfort and safety limits (≤ 1.2 m/s² for traction and ≥ -0.9 m/s² for braking), with peaks mainly around stops and speed changes. The motor power stayed below the 500 kW limit, showing positive peaks during acceleration and negative values during regenerative braking, with minor oscillations due to road slope variations. Overall energy demand for the 21 km trip was ~107.5 MJ, reflecting both traction phases and the contribution of regenerative braking.
Speed profile
Acceleration profile
Motor Power profile
Energy Consumption profile
The total energy consumption for the 21 km bus trip was estimated at ~131.1 MJ, including both traction (107.5 MJ) and auxiliary loads such as HVAC, lighting, and onboard electronics (~23.6 MJ). Accounting for a 10% charging loss, the well-to-wheel energy demand rises to ~145.7 MJ (≈40.5 kWh). Using the Dallas–Fort Worth (ERCOT All) grid emission factor of 332.9 g CO₂/kWh, the trip generates approximately 13.5 kg CO₂, or 0.615 kg CO₂ per kilometer, highlighting the environmental advantage of electric buses even under a fossil-heavy electricity grid.
- Total trip energy demand: 40.5 kWh (including auxiliaries and charging losses).
- Estimated CO₂ emissions (using Dallas–Fort Worth grid intensity, ERCOT All):
- 13.5 kg CO₂ per trip
- ≈ 0.615 kg CO₂ / km
- Comparison to diesel: Typical diesel bus emits ~1.3 kg CO₂/km.
→ The electric bus reduces emissions by ~50% under the fossil-heavy Texas grid mix.
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Daniel Avila, Mobility Engineering MSc Student
This project is licensed under the MIT License. See the LICENSE file for details.