摘要

The voltage source driver (VSD) is widely used in a conventional gate drive circuit of the power factor correction (PFC) converter. However, the fixed drive current of the VSD circuit could not optimize the switching losses, and the turn-off voltage spike across the power switch is freewill. In this letter, a real-time variable turn-off current strategy of a power switch for the PFC converter is presented. The turn-off current can be modulated real timely with the input voltage varying periodically, and the voltage spike across power switch can be controlled under the peak value that set at the peak input voltage region. The operation principle, design considerations, and the analysis of turn-off switching losses with the proposed strategy are presented by a boost PFC converter in detail. Furthermore, a prototype of the boost PFC converter was built to verify the effectiveness of the proposed strategy. As a result, the turn-off voltage spike is well limited and the efficiency is effectively improved compared with the VSD. The proposed idea can be also further extended to any other PFC converters.

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