Abstract: With the design ideas of “offline global optimization – online application – test verification”, a set of energy management strategy (EMS) for a parallel plug-in hybrid electric vehicle (PHEV) is studied by using the methods of system simulation modeling, dynamic programming and computation, genetic algorithm optimization. Through dynamic programming global optimization, an optimal control is obtained and used as a macro-guidance for developing the online EMS or an evaluation criteria for different control strategies. By using online EMS design method, a strategy not only being consistent with the PHEV characteristics but also meet the vehicle real-time control requirement is developed. The test results show that through the obtained three-level EMS, the PHEV can fully utilize the energy charged from the power grid according to different mileage. And the vehicle economic performance is improved by 50%～57%, as the power train energy flow is reasonably distributed.

Key words: Control strategy, Energy management strategy, Optimization, Plug-in hybrid electric vehicle