Silisyum Karbür Mosfet’ler İçin Kontrollü Aktif Kapı Sürücü Tasarımı

Abstract

In this thesis, an approach is presented on the active driving concept as a gate driver design technique to provide solutions for EMI, overvoltage overshoot, oscillations on current/voltage, considering the thermal requirements that occur in the system due to material properties during the use of SiC MOSFET in power electronics applications. The high frequency, speed, thermal conductivity, and small package structure of SiC MOSFET cause a decrease in efficiency due to the adverse effects of parasitic inductances and capacitances during switching transient. This situation leads to an increase in the effect of parasitics occuring in the circuit design and, accordingly, an increase in electromagnetic pollution. In designs where parasitics can not be optimized, it may appear with adverse results, up to the breakdown of the transistor. The technical solution has been presented thanks to the active gate driver printed circuit board designed to solve the SiC MOSFET usage difficulties, and efficient results have been obtained in experimental studies with negligible switching loss increase compared to driving with low gate resistance. In addition, there is a need for fast and effective short circuit and high voltage protection against the negative effects of the specified parasitic inductances and capacitances. Desaturation and active clamping protection techniques were designed with a systematic approach specific to SiC MOSFET. Concept designs that can be activated in a short time for short circuit protection and increase efficiency for high voltage protection are presented and their effectiveness has been demonstrated with experimental studies. A CMOS design has been systematically created for the comparator sections of the active gate driver that provide gate current control. The simulation and layout of the CMOS design, which is aimed to be used in the active gate driver printed circuit board (PCB) in the future, has been carried out within the scope of the thesis. In the thesis, the printed circuit board (PCB) design of the active gate driver concept for the SiC MOSFET, the design of the short circuit and high voltage protection structures, as well as the CMOS-based application specific integrated circuit (ASIC) design of the gate current control part of the active driver concept is created.