This article presents a real-time torque distribution strategy for a
single-shaft, plug-in hybrid electric vehicle (PHEV) and investigated the effect
of multiple operating parameters by using three working conditions, namely,
steady operating conditions, acceleration operating conditions, and brake
operating conditions. The corresponding experiments were performed according to
the earlier discussed three working conditions. The main conclusions of this
study are given as follows: (1) Under steady operating conditions, the engine no
longer offers torque to the motor for charging when the pedal degree is higher
than 60%. (2) Under acceleration conditions, the engine startup is sensitive to
the state of charge (SOC) decrement, maximum of 1%, and this decrement increases
with an increase in the initial SOC. (3) Under brake operating conditions, the
initial SOC may have a significant influence on the variation stability of motor
torque, especially when the braking intensity is less than 0.1.