Research Based On High Power Bi-Directional DC-DC Converter For Hybrid Electric Vehicle

As a new kind of green energy vehicle, the hybrid electric vehicle has attracted wide attention in recent years because of the energy crisis resulted from the depletion of oil resources and the increasingly severe pullution to the atmosphere caused by the exhausted gas emitted from gasoline and diesel engine vehicles. Compared with the ordinary vehicles, hybrid electric vehicle has double power sources, in which the battery-power souce system possesses the power-recovery mode and engine power providing mode in both automation and braking conditions. The real-time switch between the two modes in the battery-power souce system is the core technology for the hybrid electric vehicle to realize the goal of energy-saving and emission reduction.This article analysed the unique applications and environmental requirements of the hybrid electric vehicle, and then made analysis and comparison on the performances of a wide range of common two-way DC-DC converters. Accordingly, the author determined to use the half-bridge two-way Buck/Boost converter topology as the object of this article, and designed the parameters of the two-way DC-DC converter devices according to the relevent operation parameters.This article adopted the synchronization and complement Buck/Boost control method so as to achieve the two-way flow of energy and ensure the stability of motor bus voltage. Through analysing and calculating, the article defined the controlling circuit of the two-way DC-DC converting system on the basis of TL494, and also adopted the 2ED300C17-S Intelligent driver module as the driving circuit for the IGBT switch .By using the single chip, the commucation based on J1939 protocol which is between the two-way DC-DC converting system and position machine , as well as the real-time monitor on the data of the two-way DC-DC converting system, was achieved, and the fault protection module was designed in the communicating program.Based on theoretical analysis, the author applied the software simulation method to verify the stability of the two-way DC-DC converting system on the busbar voltage. The experimental platform was established and tested based on the simulation. The system can be able to meet the super-power operation requirement with the advantages of short time in contorlling and high efficiency in energy conversion.