Development Of The Hvbrid Range-Extender Controller For Electric Vehicles

With the intensification of energy and environmental problems,as well as the increasingly stringent requirements of the automotive industry on energy conservation and emission reduction,the world attaches more and more importance to the new energy vehicles.As a result the development of new energy automotive powertrain as well as its key components is critical.It is widely accepted that the Battery-Powered Electric Vehicles(BPEV)are the optimal choice.And the development of Range-Extended Electric Vehicle(REEV)is considered to be a smooth transition from traditional vehicles to BPEVs.At present there is still not a mature model or a range-extender(REs)product published in China.Developing the REs based on Internal Combustion Engines(ICEs),as is one of the core components of the REEVs,and its control technologies has outstanding significance.Firstly,this paper introduces the principle of hybrid-excited range-extenders(HERE)and completes its matching design according to the demands of a van.The engine selection is validated and the result of matching design of the HERE is proposed with the "Multi-Points Power Follower"(MPPF)control strategy established.And the MPPF strategy is designed to control the RE work at 5 different speeds according to is power output.This paper also presents a method for designing the excitation regulation range of the hybrid-excited generator according to the relation between speed and power.Secondly,the hardware and software design and Realization of the HERE controller is proposed based on the parameter matching of the RE.The controller consists of a main control unit and power conditioning circuit.This paper gives detailed schematic design of the main control unit and integrates it into the controller.State machine model is used to develop the software design of the RE controller.The RE control software which realized the MPPF strategy,includes basic programs,application program and OBD program.Finally,the experiment bench for RE testing is designed and built,on which the performances of the controller and the RE are verified.The static performance of the RE is obtained by bench test,which comes out with the RE’s external characteristic and load characteristic curves.The RE’s transient performance is evaluated by three groups of testing,start-up test,light-loaded start-stop test and power switching test.RE speed,output power responding to the switch of the control command and the system status are obtained as the key indication of the RE’s transient performance.Furthermore,the RE was mounted onto a van to work under the control of the VCU.Finally,it is vilified that the controller can control the RE properly and realize the MPPF strategy at actual working conditions.