Digital adaptive driving strategies for high-voltage IGBTs

Digital technology incorporated into the gate drive unit of HV-IGBTs allows new features, like automatic optimization of the gate current waveforms for achieving certain properties of the switching transients, or automatic adaptation to the operating conditions. This paper presents a digital gate unit with on-line measurement of the IGBT´s switching waveforms. Based on this, a robust control algorithm is developed to adapt the gate current waveforms to the desired switching behavior, irrespective of the operating conditions. The algorithm is implemented in a Field-Programmable Gate Array (FPGA) on the gate unit and experimentally verified for several optimization objectives using 3.3 kV and 1200 A IGBTs.