Highest Efficiency with Infineon’s 3.3 kW CCM Bidirectional Totem-Pole PFCAugust 17, 2020 by Infineon
This bridgeless totem-pole power factor correction board is intended for applications that require high efficiency and high power density such as high-end server and telecom. In addition, the bidirectional power flow capability allows this design to be used in battery chargers or battery formation applications.
The EVAL_3K3W_TP_PFC_SIC is a bridgeless totem-pole power factor corrector evaluation board, with bidirectional capability enabled by the CoolSiCTM MOSFET 650V, CoolMOSTM Superjunction Power MOSFETs, isolated EiceDRIVERTM ICs, CoolSETTM QR flyback controller and XMCTM microcontroller. The 3.3 kW totem-pole PFC operates in high line (from 176 to 265 V) with a nominal bulk voltage of 400 V and a nominal output power of 3.3 kW. This design targets mainly applications that require highest efficiency (99%) and high power density (73 W/in3), matching the requirements of high-end server and telecom applications. In addition, its bidirectional power flow capability, enabled by a digital control, allows its usage in other applications, such as battery chargers and battery formation.
The bridgeless totem-pole topology is intrinsically bidirectional, with the possibility to switch between the two operation modes of PFC (AC-DC) or Inverter (DC-AC) through a selection switch
in the main board.
The integrated digital control provides not only proper steady-state performance (Total Harmonic Distortion < 10% and Power Factor > 0.95), but also robust behavior in dynamic conditions and Power Line Disturbance. Further, the CCM bridgeless totem-pole PFC comes with an implemented average current control with duty cycle feed-forward. The Graphical User Interface (GUI), which is provided with the board, allows to set dead time characteristic and to control the power in inverter operation. The dead time modification allows to maximize the totem-pole performance and to test CoolSiCTM devices with different RDS(on), enabling cost down solutions.