A unique electric transmission concept, consisting of two traction motors in tandem, for use in automotive vehicles is described. The device does away with the requirement of intermittent current supply at low speeds, and is shown to be superior to conventional electric motor drives with regard to efficiency, flexibility of torque-speed requirements, control, and adaptability to regenerative braking. The electric motor-transmission can operate in either the differential, single-motor, or additive mode, producing both forward and reverse speeds while covering the entire spectrum of torque, speed, and power required by an automotive vehicle. A detailed study of a 7.5 kW model was performed, providing performance data, current drain, output, efficiencies, and other relevant system characteristics. Based on this data, a preliminary design is formulated including estimates of size, weight, and cost. A catalog of specifications for power ratings ranging from 3.7 kW to 15 kW is included, so that the automotive designer may select a unit most appropriate to his vehicle. Recommendations are made for advancing the technology of high-speed dc machinery and a development program for the construction and testing of an appropriate motor-transmission prototype for demonstration purposes. (ERA citation 03:037606)
Characterization Study of an Electric Motor-Transmission System for Electric Vehicles
1977
112 pages
Report
No indication
English
ELECTRIC POWER TRANSMISSION SYSTEM FOR ELECTRIC VEHICLES
European Patent Office | 2024
|Tema Archive | 1975
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