Active Gate Driver With Variable IGBT Input Capacitance Capable Of Suppressing High-Frequency Common Mode Currents And Switching Losses

Power semiconductor devices such as IGBTs and MOSFETs generate electromagnetic noise and switching losses during switching. In conventional gate drive circuits using a simple gate resistor (R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g</inf>), electromagnetic noise and switching losses are a trade-off, so the current challenge is to reduce both. Active gate drivers are one of the methods to improve the trade-off between electromagnetic noise and switching losses. However, the R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g</inf>-variable active gate driver of previous research requires a dedicated gate driver, which is complicated and increases cost. We propose a new active gate driver that controls the input capacitance by adding a capacitor in parallel between the gate and emitter of the IGBT during switching. This paper reports that the proposal gate drive circuit improves the trade-off between high-frequency noise and switching loss at turn-off. And by changing the capacitance value of the added capacitor, the reduction of high-frequency noise and switching losses can be adjusted, indicating that stable operation is possible regardless of the magnitude of the parasitic inductance of the main circuit.