The Vienna toplogy is essentially a three-phase diode bridge with an integrated boost converter and is suited to fast electric vehicle (EV) charging and other high power automotive and industrial applications such as medical, aerospace, defence and data centres, with high avalanche/repetitive unclamped inductive switching (UIS) and high short-circuit withstand ratings.
Compared to single-phase PFC and two-level, six-switch boost pulse width modulated (PWM) rectifier designs, the topology allows for continuous conduction mode operation with low distortion and a 98 percent efficiency at high loads as well as a smaller form factor than designs using silicon IGBTs.
“As the automotive market transitions toward more hybrid electric vehicle (HEV) and battery electric cars, SiC allows for better efficiency, resulting in better mileage. This continues to drive high demand for these SiC devices in our portfolio, as well as our other high-reliability product offerings,” said Leon Gross, vice president and business unit manager for Microsemi’s Discrete and Power Management group. “After successfully releasing our SiC MOSFET and diode product portfolio over the past few years, our new three-phase three-switch three-level PFC reference design is a concrete example of how to leverage these parts in demanding applications that showcase its ruggedness, high performance and overall value.”
The reference design includes design files for use with the Microsemi SiC diodes and MOSFETS, open source digital control software and a user guide. It also includes a detailed 3D mechanical and thermal design with an integrated fan and cooling channel to reduce thermal resistance and total system size. Its printed circuit board (PCB) layout was developed with considerations for safety, current stress, mechanical stress and noise immunity, and the reference design package features ready-to-use hardware and verified open source software to reduce the technical risk of high power switching designs while accelerating product time to market.
The reference design is available from Microsemi at www.microsemi.com/product-directory/discretes/3613-silicon-carbide-sic