Continuously variable transmission: assessment of applicability to advanced electric vehicles

Technical Report · Thu Jan 01 00:00:00 EST 1981

OSTI ID:5656083

Loewenthal, S H; Parker, R J

A brief historical account of the evolution of continuously variable transmissions (CVT) for automotive use is given. CVT concepts which are potentially suitable for application with electric and hybrid vehicles are discussed. The arrangement and function of several CVT concepts are cited along with their current developmental status. The results of preliminary design studies conducted under contract to NASA for DOE on four CVT concepts for use in advanced electric vehicles are discussed. For these studies a 1700 kg (3750 lb) vehicle with an energy storage flywheel was specified. Requirements of the CVTs were a maximum torque of 450 N-m (330 lb-ft), a maximum output power of 75 kW (100 hp), and a flywheel speed range of 14,000 to 28,000 rpm. System life was to exceed 2600 hours at a 90% probability of survival. Efficiency, size, weight, cost, reliability, maintainability, and controls were evaluated for each of the four concepts. The design studies were performed by Garrett/AiResearch (toroidal traction CVT). Battelle Columbus Labs (steel V-belt CVT), Kumm Industries (flat belt variable diameter pulley CVT), and Bales-McCoin Tractionmatic (core-roller traction CVT). All CVTs exhibited relatively high calculated efficiencies (86 to 97%) over a broad range of vehicle operating conditions. Estimated weight and size of these transmissions were comparable to or less than an equivalent automatic transmission.

• Research Organization: National Aeronautics and Space Administration, Cleveland, OH (USA). Lewis Research Center
• DOE Contract Number: AI01-77CS51044
• OSTI ID: 5656083
• Report Number(s): DOE/NASA/51044-23; NASA-TM-82700; CONF-811010-6; ON: DE82001354
• Resource Relation: Conference: 6. electric vehicle council symposium, Baltimore, MD, USA, 21 Oct 1981
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
ELECTRIC-POWERED VEHICLES
MECHANICAL TRANSMISSIONS
HYBRID ELECTRIC-POWERED VEHICLES
DESIGN
EFFICIENCY
OPERATION
CONTROL EQUIPMENT
FLYWHEELS
RELIABILITY
SIZE
THEORETICAL DATA
WEIGHT
DATA
EQUIPMENT
INFORMATION
MACHINE PARTS
MECHANICAL ENERGY STORAGE EQUIPMENT
NUMERICAL DATA
VEHICLES
330300* - Advanced Propulsion Systems- Electric-Powered Systems
330602 - Vehicle Design Factors- Engine-Transmission Matching
330400 - Advanced Propulsion Systems- Hybrid Systems