Novel zero-current-transition circuit for three-phase buck rectifiers

ZCT circuits have already been proposed in the past and are becoming more and more popular to high power rectifiers and inverters where bipolar devices hare to be used (IGBTs or even BJTs). Although ZCT techniques hare already been applied to three phase BOOST type topologies, no ZCT circuits have been proposed for three phase BUCK type topologies. We propose a new load independent ZCT circuit for a three phase BUCK type rectifier which achieves a high noise reduction, voltage stress reduction and zero current transitions to almost all transitions of the rectifier's switches including the additional auxiliary switches.