Design of a digital control system for a half-bridge converter
Typ
Examensarbete för masterexamen
Master Thesis
Master Thesis
Program
Publicerad
2006
Författare
Lernvall, Tobias
Olsson, Rosalie
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
In this exam thesis an analogue control system for a module consisting of two half-bridge converters has been replaced by a digital control system derived in this thesis. The digital control system has been derived using the existing analogue control system as a reference to find the important functions that has to be included in the system. The digital control system should be able to handle parallel and serial connected converters as well as single converter operation. The analogue control system has been analysed in the beginning of the thesis and the important functions has been listed to serve as a guideline of how the digital control system should function. After listing the functions of the analogue control system a digital component has been chosen that can perform some of these functions, the digital components studied in this thesis are FPGAs and microcontrollers. The chosen component to replace some of the functions of the analogue control system is a microcontroller, a XC164CM from Infineon. This component has been programmed in assembler and C and the complete program has been tested on the module, to be able to connect the microcontroller to the module, a new PCB has been designed and constructed. Before connecting the digital control system to the module the system has been tested with the help of a step-down converter, constructed during the thesis work, to avoid damaging the module. The results from the tests of the constructed digital control system are presented in the thesis, according to the tests performed on the module the system works as intended. One of the goals with the regulation was to not increase the output voltage ripple compared to the analogue control system, this goal was not completely reached. This may have to do with the connection used in the tests, the microcontroller are not placed on the same PCB as the other components needed for the system and this may increase the system?s sensitivity to noise. To create a complete product the microcontroller and the other components has to be placed on the same PCB and some other functions, not included in this thesis, has to be implemented.
Beskrivning
Ämne/nyckelord
Elkraftteknik , Electric power engineering