Digital Adaptive Driving Strategies for High-Voltage IGBTs

Digital technology incorporated into the gate drive unit of high-voltage insulated-gate bipolar transistors (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 online measurement of the switching waveforms of an IGBT. 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 on the gate unit and experimentally verified for several optimization objectives using 3.3-kV and 1200-A IGBTs.