Series-Connection of Silicon Carbide MOSFET Modules using Active Gate-Drivers with dv/dt Control

TR Number

Date

2019-12-04

Journal Title

Journal ISSN

Volume Title

Publisher

Virginia Tech

Abstract

This work investigates the voltage scaling feasibility of several low voltage SiC MOSFET modules operated as a single series-connected switch using active gate control. Both multilevel and two-level topologies are capable of achieving higher blocking voltages in high-power converter applications. Compared to multilevel topologies, two-level switching topologies are of interest due to less complex circuitry, higher density, and simpler control techniques. In this work, to balance the voltage between series-connected MOSFETs, device turn-off speeds are dynamically controlled on active gate-drivers using active gate control. The implementation of the active gate control technique (specifically, turn-off dv/dt control) is described in this thesis. Experimental results of the voltage balancing behavior across eight 1.7 kV rated SiC MOSFET devices in series (6 kV total dc bus voltage) with the selected active dv/dt control scheme are demonstrated. Finally, the voltage balancing performance and switching behavior of series-connected SiC MOSFET devices are discussed.

Description

Keywords

series-connected devices, silicon carbide (SiC), metal-oxide-semiconductor field-effect transistor (MOSFET), gate-driver design, active gate control, active dv/dt control, medium-voltage, voltage balancing

Citation

Collections