A Study on Parallel Operation of Power MOSFET

• Main Author: 莊居成
• Other Authors: 陳建富
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/01865813183792651557

碩士 === 國立成功大學 === 電機工程學系 === 85 === 　　In this thesis, the parallel and protective methods of power MOSFET are investigated, and this method is applied on uninterrupted power supply (UPS) to enhance its power capacity. 　　In simple parallel method of power MOSFET, a feedback resistor is connected in series to the source terminal of power MOSFET. Although it makes the current balanced, the power loss is increased opposite and this method is unsuitable applied the systems of large current. In order to overcome this drawback, a new structure using current feedback method is proposed. In this method, a current transducer is applied to transfer the switch current to voltage signal, which used to adjusted the gate-source voltage of power MOSFET. Not only the switch current in parallel are balanced, the power loss in feedback circuit is decreased. Moreover, to prevent the damage from over current and voltage surge to power MOSFET, wer designed a protective circuit to suppress the over current and voltage surge. 　　Finally, two parallel MOSFETs are applied to a lkVa inverter to demonstrate the performance of the proposed scheme.