Research On VCU For Pure Electric Vehicle

As a kind of new energy vehicles, Pure Electric Vehicles (PEV) have gooddevelopment prospect. VCU (Vehicle Control Unit) is one of key technologies for PEVresearch. High efficient and reliable energy management strategy can effectively take use ofLithium battery’ energy to improve the trip range mileage. This paper is to study therecovery strategy of braking energy and complete the design of VCU on the basis of studyboth home and abroad.Firstly, the history and development of PEV are introduced in this paper. Then keytechnologies for the PEV are introduced, including VCU, lithium battery technology,energy management system (EMS), motor drive technology, etc.The research of VCU is one of the key technologies for the study of PEV which playsan important role in the control of the vehicle and the energy optimization. The compositionand working principle of VCU are studied, function analysis are also given in this paper.Recycling of braking energy is one of main functions of VCU. The distribution ofbraking force between mechanical braking and electrical braking is a puzzle. Based on thestudy of the existing braking energy recovery control strategy, a reasonable braking energyrecovery control strategy is put forward.After analyzing the research of the VCU both home and abroad, the composition andprinciple of VCU are studied and the total design project is proposed. A vehiclecommunication network based on CAN bus is put forward.A fuzzy controller is designed.The speed and SOC are set for inputs while theregenerative braking scaling factor is set for output. Membership functions and fuzzy rulesare designed using MATLAB fuzzy logic toolbox. Control strategy for braking energyrecovery is simulated in Advisor software.The design of the hardware for VCU is made according to the idea of modulardesign. Meanwhile the ground and application software are completed. Someanti-interference measures are adopted to ensure the reliability of VCU. At last,basic functions of VCU are verified by the designed experiment.