Closed-loop IGBT gate drive featuring highly dynamic di/dt and dv/dt control

Abstract

In this paper, a closed-loop active IGBT gate drive providing highly dynamic diC/dt and dvCE/dt control is proposed. By means of using only simple passive measurement circuits for the generation of the feedback signals and a single operational amplifier as PI-controller, high analog control bandwidth is achieved enabling the application even for switching times in the sub-microsecond range. Therewith, contrary to state of the art gate drives, the parameter dependencies and nonlinearities of the IGBT are compensated enabling accurately specified and constant diC/dt and dvCE/dt values of the IGBT for the entire load and temperature range. This ensures the operation of an IGBT in the safe operating area (SOA), i.e. with limited turn-on peak reverse recovery current and turn-off overvoltage, and permits the restriction of electromagnetic interference (EMI). A hardware prototype is built to experimentally verify the proposed closed-loop active gate drive concept.