Design Of Interleaved Bidirectional DC/DC Converter For Electric Vehicles

As the energy crisis and environment pollution are deteriorating, electric vehicles have drawn wide attentions because of their great advantages in technology, economy and environment protection. It is well known that bidirectional DC/DC converter used for electric vehicles improve the performance of the automobiles. To meet the special requirements of electric vehicles installed with super-capacitors, an interleaved bidirectional DC/DC converter with low voltage, high current and fast dynamic response characteristics is designed.Different operation modes in corresponding with diverse conditions of the electric vehicles are analyzed firstly. In order to enhance the current capacity and power density, interleaving parallel technology is introduced. Working principles and parameters of the interleaved bidirectional DC/DC converter are expounded according to the demand of Shanghai Automobile Group. Loss distribution and efficiency curve are obtained though loss breakdown.In this paper, dynamic models of this bidirectional DC/DC converter under different operation modes are derived. Then design of the hardware circuit and realization of the control arithmetic are described detailedly in the following thesis. Controllers corresponding to different working modes are also devised to improve the performance of this system.Experiments of steady state, temperature raise tests and dynamic experimentations for a 5KW prototype are done to verify the theoretical analysis is plausible. The experiment results of this bidirectional DC/DC converter installed in a electric vehicle of Shanghai automobile group limited liability company are given as well.