Design and Implementation of Series Multi-switch Modules for High Pulsed Voltage Generator

• Main Authors: Shao Tsung Peng, 彭紹宗
• Other Authors: S. Y. Tseng
• Format: Others
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/87084494269814183277

碩士 === 長庚大學 === 電機工程學系 === 99 === The main objective of this thesis is to design and implement series multi-switch modules for high pulsed voltage generator. In the research, the proposed generator adopts LLC resonant converter to form high voltage generator and switches with low-voltage ratings connected in series to form pulse-voltage switch set. They can generate bipolar voltage for liquid food sterilization. In order to sterilize different bacteria, a programmable pulse voltage width is used in the proposed generator to achieve an optimum effectiveness of sterilization. In the proposed generator, the LLC resonant circuit is used to recover the energy trapped in leakage inductance of transformer and to operate switch with zero-voltage switching feature for increasing conversion efficiency. Moreover, the LLC one can avoid to generate a large resonant current which is generated between leakage inductance of primary side and the equivalent capacitor reflected from secondary side to primary side. It will result in a higher voltage stress across switches and current stress through ones. Compared with a conventional full-bridge converter with hard-switching circuit, the proposed generator can reduce voltage and current stresses of switches and increase conversion efficiency due to soft-switching features. Finally, a prototype of high pulse-voltage generator under output voltage of ±20 kV and maximum output power of 2.5 kW has been implemented to prove the feasibility of the proposed generator.