Holmes, A., Liu, J., Ames, D., Neelakantan, V. et al., "General Motors Electric Variable Transmission for Cadillac CT6 Sedan," SAE Technical Paper 2016-01-1150, 2016, doi:10.4271/2016-01-1150.
An all-new electric variable transmission (EVT) developed by General Motors for rear-wheel-drive products is at the center of the plug-in hybrid electric vehicle (PHEV) propulsion system for the Cadillac CT6. This transmission includes two integrated electric motors, planetary gearing, and hydraulic clutches. It is capable of power-split-hybrid operation in continuously variable transmission (CVT) ratio ranges, parallel-hybrid operation in fixed gear ratios, and all-electric propulsion in different ratio combinations. Transmission operation, mechanical design, controls design, motor design, and output capability are explained, and simulation results used as the benchmark for final development are included. All-electric launch and driving, selectable regeneration, and power blending with the turbocharged engine provide smooth and seamless propulsion through the entire driving range.