Method of Predicting Hill Climbing Performance in Batteryless Motorized-Four-Wheel-Drive System

We have predicted the hill climbing performance of a batteryless motorized-four-wheel-drive (M4WD) system. With this type of M4WD system, the engine drives the front wheels, and an electric motor drives the rear wheels. The electrical power to the motor is supplied directly by the M4WD generator (water-cooled alternator for M4WD use only) driven by the engine. The system is small and simple due to this batteryless powertrain. However, predicting hill climbing performance is complex due to the power tradeoff between the front and rear wheels. We clarify nonlinear mechanical and electrical power flow models, and discuss how our M4WD vehicle simulator using these power flow models is able to predict hill climbing performance. The performance we predicted agreed well with the actual performance of a prototype vehicle.