Applying FPGA Control Without ADC to Multi-Output DC-DC Converter

• Main Authors: Cheng-Han Tsai, 蔡承翰
• Other Authors: 胡國英
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/qynnck

碩士 === 國立臺北科技大學 === 電機工程系研究所 === 97 === In this thesis, the forward converter with multiple outputs is used to realize a system with fully-digitalized control without any analog-to-digital converter (ADC) used. In such a circuit, each output voltage can regulate itself via feedback control. Aside from this, the output voltage with the largest output current takes not only voltage control but also interleaved control and current sharing control. If such a system takes fully-digital control, then the number of ADCs used is large and hence the corresponding cost is expensive. Therefore, the sampling of multiple output voltages and two-phase currents without any ADC is presented herein. For the system control to be considered, an additional nonlinear control strategy is presented and added to the existing proportional integral derivative (PID) controller, so as to enhance the load transient response. In this paper, the multiple-output forward converter has three output voltages of 12V, 5V and 3.3V, where the output voltage of 3.3V possessing has the largest output current takes interleaved control and current sharing control. Via mathematical derivation and simulated waveforms, the feasibility of the proposed structure topology and control strategy can be verified. Furthermoore, the field programmable gate array (FPGA) is used as a control kernel of the system, so as to demonstrate the effectiveness of the proposed structure topology and control strategy.