Active Voltage Balancing with Seamless Integration into Dual Gate Driver for Series Connection of SiC MOSFETs

The versatility of half-bridge configuration of silicon carbide (SiC) metal-oxide-semiconductor field-effect transistor (MOSFET) power module contributes to its widespread adoption, highlighting the popularity and significance of its corresponding dual gate driver (D-GD) design. For use in high voltage converter designs, configuring the half-bridge module as series connection with effective voltage balancing (VB) can make it aggregated into a single device with double voltage rating. Hence, in this letter, a novel active VB scheme with seamless integration into D-GD is proposed. Different from existing passive VB methods with significant loss and active VB strategies with high cost and complexity, the proposed active VB circuitry only consists of few low voltage and low power BJTs, resistors and capacitors, which offers the prominent advantages of ease of implementation and integration, low cost, and high reliability. Analysis is provided to illustrate the working principle, followed by the criterion for parameter selection. Finally, the experimental results based on 3.3kV half-bridge SiC MOSFET power module are given to demonstrate operational performances.