Research On Extended Range Electric Bus’s APU Control System Based On PWM Rectifier

Currently, the serious shortage of energy and environmental issues promotedthe development of electric vehicles, but battery technique is limited because ofthe problem of energy density and durability, so pure electric vehicles is difficultto have a major breakthrough in the short term. Compared with pure electricvehicles, extended range electric vehicles increase by auxiliary power unit (APU)for power battery charging in massive structure, auxiliary power unit whichmakes extended range electric vehicles not only ensures the driving range andbattery durability, but also prominent advantages of electric power withcomparison of fossil fuels. Therefore, the study of auxiliary power unit of coreelectric vehicles components has great practical significance.The dissertation makes three-phase voltage source PWM rectifier circuit asthe primary circuit of APU control system, the program cans not only controlledAC/DC conversion performance, but also sinusoidal current, and running atunity power factor. Energy can transport on two-way, thus realization of greenenergy transformation is done. Firstly, discussing work principle and controlstrategy of PWM rectifier, and detailing the mathematical model and controlstrategy of three-phase voltage source PWM rectifier.Secondly, according to extended range electric bus power system parameters,make selection of APU components, determine the parameters of the engine andgenerator. On this basis, finished with a16-bit microcontroller InfineonXC164CS as the core controller hardware design and software development.Finally, build a test bench for the APU control system for debugging,collecting the experimental data. The results show that the APU control systemdesigned to achieve the initial design requirements, and achieve the variouscontrol functions. The PWM rectifier scheme in the paper makes the AC side ofmain circuit tends to be sinusoidal waveform. This shows that the AC side of the harmonic content of the main circuit is smaller, the loss of the generator isreduced, and the power generation efficiency is increased.