of Start-up Strategies of Dual Mode CVT Powertrains

Abstract:

0.8s。 Conventionally, the start-up control strategy of dual mode CVT has focused on obtaining maximum output power of the combination of engine and torque converter; however, this strategy did not pay attention to the efficiency of the metal V-belt unit, which also influenced the start-up characteristics of the system. A start-up control strategy considering both TC and metal V-belt efficiency was proposed. An optimal algorithm was developed to calculate the target CVT ratio in order to obtain maximum driving power with consideration of both TC and metal V-belt efficiency. Simulation and experimental results indicated that, when lock-up speed was 30 km/h and start-up throttle opening was 20%, working time of the TC during the start-up process was reduced by about 0.8 s after the optimization.