2021 Volume 141 Issue 7 Pages 532-541
MOSFETs generally have excellent switching characteristics, and their switching losses can be reduced by synchronous rectification. Furthermore, using the body diode of MOSFET, it is possible to remove any external freewheeling diodes. However, the body diode of a SiC-MOSFET has two major problems: the on-state voltage of the body diode is high, and a reverse recovery current occurs. These problems are appeared by the current flowing through the body diode during the dead time of synchronous rectification. To prevent these problems, we propose a synchronous rectification scheme with substantial zero dead time control. In this type of control, we apply a circuit to detect current by integrating the voltage generated in the wiring inductance of the semiconductor device. A short-circuit current flows by substantially eliminating the dead time, but it is limited by providing a period of suppressed gate voltage. In this paper, we present the principle of this scheme, measurement results of the loss when the MOSFET is turned-on/off, and control parameters. Using this scheme, it was confirmed that the loss when the MOSFET is turned-on/off could be reduced.
The transactions of the Institute of Electrical Engineers of Japan.C
The transactions of the Institute of Electrical Engineers of Japan.B
The transactions of the Institute of Electrical Engineers of Japan.A
The Journal of the Institute of Electrical Engineers of Japan