Optimization of Bidirectional DC/DC Converter for Electric Vehicles Based On Driving Cycle

  • Yutao, Luo (School of Mechanical and Automotive Engineering, South China University of Technology) ;
  • Feng, Wang (School of Mechanical and Automotive Engineering, South China University of Technology)
  • Received : 2017.01.20
  • Accepted : 2017.06.04
  • Published : 2017.09.01


As a key component of high-voltage power conversion system for electric vehicles (EVs), bidirectional DC/DC (Bi-DC/DC) is required to have high efficiency and light weight. Conventional design methods optimize the Bi-DC/DC at the maximum power dissipation point (MPDP). For EVs application, the work condition of the Bi-DC/DC is not strict as the MPDP, where the design method using MPDP may not be optimal during travel of EVs. This paper optimizes the Bi-DC/DC converter targeting efficiency and weight based on the driving cycle. By analyzing the two-phase interleaved Bi-DC/DC for hybrid energy storage systems (HESS) of EVs, its power dissipation is calculated, and an efficiency model is derived. On this basis, weight models of capacitor, inductor and heat sink are built, as well as a dynamic temperature model of heat sink. Based on these models, a method using New European Driving Cycle (NEDC) for optimal design of Bi-DC/DC which simultaneously considered efficiency and weight is proposed. The simulation result shows that compare with conventional optimization methods revealed that the optimization approach based on driving cycle allowed significant weight reduction while meeting the efficiency requirements.


Bidirectional DC/DC converter;Efficiency increase;Optimal design;Weight reduction


Supported by : Guangdong Provincial Department of Science and Technology


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