Multi-Speed Transmission For Commercial Delivery Medium Duty PEDVs
- Eaton Corp., Menomonee Falls, WI (United States)
Successful completion of the proposed project will set a course for improving quality of life by overcoming key challenges in the gearbox for commercial-delivery, medium-duty, plug-in electric drive vehicles: It will reduce US dependency on foreign oil through the use of electric driven propulsion instead of fuel driven. It will reduce health risks by replacing tailpipe emissions in densely populated city centers. Finally, it will improve the performance-cost basis to meet or exceed the expectations of the targeted medium duty vehicle fleet owners and the independent customers. The proposed multi-speed transmission will narrow motor operation to the peak efficiency region, thereby increasing the electric powertrain efficiency to help close the range gap. Further, it will enhance customer satisfaction by improving vehicle acceleration, top speed and gradeability over the baseline. The project was conducted in three budget periods: In BP1: Technology Development, High-level vehicle powertrain models were used to optimize candidate transmission architectures and ratios along with a variety of traction motor characteristics for concept selection. The detailed driveline designs and component dynamics were investigated to meet medium-duty EV requirements; In BP2: Technology Development and Prototype Demonstration, The modeling and simulations with multi-speed transmissions were extended to other MD and HD EV platforms. Clean sheet design of a compact, lightweight, flexible, and modular, four-speed transmission was completed. Development of novel shifting and controls strategies were started and procurement of the prototype transmission and the controller hardware was begun; In BP3: Technology Integration, Testing, and Demonstration, Prototyping the four-speed automated mechanical transmission was completed. The transmission controls system and software development and preliminary gearbox dyno tests were done at Eaton. ORNL conducted integrated powertrain HIL tests. One of the prototype units was fully integrated into a Proterra BE35 demonstration electric bus. The shift control strategy was fine-tuned on the integrated vehicle at Eaton Marshall Proving Grounds. NREL tested the vehicle and validated the performance gains. Simulations predicted up to 20% increase in system energy efficiency depending on drive cycles, a top speed of greater than70 mph on flat road, 40% faster acceleration and a doubled gradeability with four-speed transmission as compared to the baseline EVs. Chassis Dyno Tests at NREL verified the simulation results of Eaton team and the HIL test results of ORNL team. The new four-speed EV transmission is efficient, reliable, modular, scalable, light weight, small size, and will be affordable. Furthermore, four-speed transmission enables downsizing of motor, battery and final drive, thereby reducing the total system cost.
- Research Organization:
- Eaton Corp., Menomonee Falls, WI (United States); National Energy Technology Lab. (NETL), Pittsburgh, PA, and Morgantown, WV (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V); Proterra Inc., Burlingame, CA (United States)
- DOE Contract Number:
- EE0006843
- OSTI ID:
- 1418158
- Report Number(s):
- DOE-EATON-0006843
- Country of Publication:
- United States
- Language:
- English
Similar Records
Accessory Hybridization for Medium- and Heavy-Duty Trucks
Baseline tests of the GE-100 centennial electric passenger vehicle
Related Subjects
Medium duty electric vehicle (MD-EV)
heavy duty electric vehicle (HD-EV)
multi-speed transmission
4-speed transmission
automated mechanical transmission
yy shifter
electric bus
electric delivery truck
HIL test
chassis dyno test
efficiency
efficiency gain
motor efficiency map
transmission efficiency
acceleration
gradeability
duty cycle
Altoona tests
Autonomie
simulation
modeling
regeneration
adaptive control strategy
transmission control unit
NVH
business case