The Research Of DC-DC Converter Based On FPGA

Compared with traditional analog control, DC-DC converter digital control has manyprominent advantages. Digital control can realize complex control strategy, easy to realizeintelligent system and greatly improve the reliability and flexibility of system. Therefore,digital control become an important direction of current power technology development. Thispaper mainly research the Buck DC-DC converter digital control, and a Buck DC-DCconverter based on FPGA was designed and implemented.According to the steady-state and dynamic performance of the switching power supply,the digital hysteresis current control method is designed based on analysis and research of thevarious control mode. Analyzed the Buck converter dynamic response of load changing andstarting process based on digital hysteresis current control. According to technicalrequirements of the power supply design, the design of main buck converter circuitcomponents parameters, design of power switch driver circuit, design of sampling circuit,selection of FPGA and A/D converter and design of peripheral circuit are all accomplished.Simulink simulation of the digital control Buck converter model verified the correctness ofthe control strategies and the reliability of the system. By using VHDL, frequency module,control strategies module, A/D module，hysteresis band module and overcurrent protectionmodule are all designed in Quartus II, and the whole system and each module are simulatedand verified, simulation result that meets the design requirements are acquired. Finally, thehardware of Buck DC-DC converter based on FPGA control are produced and debugged,input voltage changing and load changing of the designed circuit are tested and analyzed.The test results of experiment show that theoretical analysis of converter is correct, thecontrol strategy is feasible and the performance meet the design requirements.