News

Silicon Carbide enables 30kW Three-Phase Vienna PFC Reference Design

May 22, 2018 by Paul Shepard

Microsemi Corporation today announced the availability of its new scalable 30kW, three-phase Vienna power factor correction (PFC) topology reference design developed in collaboration with North Carolina State University and featuring Microsemi's silicon carbide (SiC) diodes and MOSFETS.

This scalable, user-friendly solution is suited for fast electric vehicle (EV) charging and other high power automotive and industrial applications, providing customers with more efficient switching as well as high avalanche/repetitive unclamped inductive switching (UIS) and high short-circuit withstand ratings when utilizing the company's robust SiC MOSFETs and diodes.

The active rectifier PFC reference design, along with other solutions in the SiC product family, will be demonstrated June 5-7 in hall 6, booth 318 at PCIM Europe 2018, held at the Exhibition Centre in Nuremberg, Germany.

"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," Gross added.

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Microsemi's user-friendly 30 kW three-phase PFC reference design includes design files for use with the company's next-generation SiC diodes and MOSFETS, open source digital control software and a user guide. The topology offers advantages over single-phase PFC and two-level, six-switch boost pulse width modulated (pwm) rectifier designs, which include operation in continuous conduction mode with extremely low distortion, reduced switching losses on power devices of approximately 98 percent for high efficiency and a compact form factor compared to Si/IGBT solutions.

The reference design also offers a detailed 3-D mechanical and thermal design with an integrated fan and cooling channel to reduce thermal resistance and total system size. Its printed circuit board 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.

Features include:

  • 3-phase 380Vac or 400Vac, 50 or 60 HZ
  • Capable of 20kW initially, 30kW eventually (MSC040SMA120B to MSC035SMA070B / MSC015SMA070B, MSC030SDA120B)
  • Switching frequency: 140kHz
  • Design for 20% over voltage on the line. At low line current is reduced to limit to the nominal line current.
  • Maximum ambient - 60C.
  • Maximum conductor temperature - 90C.
  • Up to 4 oz copper
  • Gate driver UCC5390S
  • Design dc link electrolytic cap are 1mF, composed of 470V caps in series. The value is determined more by the load stability requirement than the PFC. The 1mF value was chosen as a minimum that can handle the ripple current.

In addition to its suitability for fast EV/HEV chargers and high power three-phase power supplies in the automotive and industrial markets, Microsemi's new active three-phase PFC reference design can also be used in medical, aerospace, defense and data center markets. This reference design adds to the company's overall SiC solutions portfolio, which can also be used for HEV/EV charging, conductive/inductive onboard charging (OBC), dc-dc converters, EV powertrain/traction controls, photovoltaic (PV) inverters and actuation applications.