Control Strategy Comprehensively Considering Fuel Economy and Drive Comfort of Duel-Axis-Parallel PHEV

In this paper, in order to comprehensively consider the economy and comfort of the special duel-axis-parallel PHEV, a vehicle control strategy composed of a shift strategy based on dynamic programming(DP), a rule-based energy management strategy and a dynamic coordinated control strategy based on motor torque compensation is proposed. A vehicle model which can show the dynamic characteristics of shifting and engine start-stop process is constructed for simulations. Shift strategy is extracted from the optimization results obtained by dynamic programming(DP). The energy management strategy takes the fuel economy of engine as a major consideration and the rule is determined by characteristics of engine, motor and battery. In the dynamic coordinated control strategy, an open-loop motor torque control based on clutch torque estimation is presented. Simulation is carried out on typical driving cycles. And the results indicate that the proposed vehicle control strategy can improve the fuel economy and reduce longitudinal impact caused by shifting and operated mode changing.