Three-Phase Boost-Type PFC Rectifier (AC/DC)

Vienna Rectifier Basics

Vienna Rectifier Papers

Vienna Rectifier Design


Vienna Rectifier 1 - Overview

Characteristics and Advantages of the Vienna Rectifier 1 (as compared to the two-level six-switch boost-type PWM rectifier)
  • Three-phase three-level three-switch PWM rectifier with controlled output voltage; three-wire input, i.e. no connection to the neutral required
  • Sinusoidal input currents, in principle no low-frequency harmonics, unity power factor operation, i.e. ohmic fundamental mains behavior
  • Boost-type system, i.e. continuous input current
  • Unidirectional power flow
  • Power circuit of low complexity with only three active switches and/or three gate drive circuits, a control failure does not result in a short circuit of the DC output voltage, guaranteeing in high reliability and low costs
  • High power density; the three-level characteristic does reduce input-current ripple and/or input inductor volume for given ripple
  • Stability of neutral point potential is guaranteed by a simple control
  • Three-level characteristic does reduce the blocking voltage stress on all power semiconductor components by a factor of 2
  • Low conducted common-mode EMI emission due to switching of always only half the output voltage
  • Straightforward control scheme, low complexity, low realization effort
  • Switching losses reduced
    • by a factor of 2 according to reduced turn-off voltage
    • by a factor of about 2 according to possibility of using ultra fast recovery free-wheeling diodes
    • by a factor of about 1.5 according to reduced switching frequency due to the three-level characteristics
  • Total reduction of switching losses theoretically by a factor of 6 result in reduction of the total losses of about 40% for a typical switching frequency (48kHz) - the efficiency at rated output power has been verified experimentally to be 97.5% for a 10kW system operating at 400Vrms line-to-line input voltage (output voltage is 800V DC).
  • Operation at heavily unbalanced mains voltages and/or in case of a mains failure (two-phase operation) possible, the proposed control schemes do guarantee an ohmic mains behavior also in this case
  • Ongoing development, e.g. 2U-unit with 12kW rated power and wide input voltage range (320V...530V) system footprint: 16cm x 25cm
  • Development of a 1U-unit of same rating under way (switching frequency of 500kHz, SiC technology)
  • Fully documented mixed signal control board (analog current control and digital voltage control, start-up management, failure management etc.) available as evaluation board from the Power Electronic Systems Laboratory/ETH Zurich
  • Fully documented power circuit hardware 10kW/400V input, 800V DC output available from the Power Electronic Systems Laboratory/ETH Zurich
  • Fully digital control under development
Possible fields of applications of the Vienna Rectifier are
  • Telecommunications power supply
  • Uninterruptable Power Supply (UPS)
  • Input stage of AC drive converter systems
  • Industrial process technology (input stage of electronic welding current sources, plasma power supplies, laser power supplies etc.)
  • Basically all areas where six-switch converters are used for achieving sinusoidal mains current and controlled output voltage but no energy feedback from the load into the mains is required.