New bidirectional sinewave-modulated series resonant power conditioning system with high-frequency AC link

A Venturini based modulation technique for a new isolated AC/AC power converter

“…State 4) At t=t 4 , the switch s0o is turned off because s7o is in on state. In this state, only two switches i.e.…”

“…The scenario can be worse for converters with a significantly large number of devices such as modular multilevel converters [2]. Employing a line frequency transformer can provide isolation but results in high cost and large volume and weight [3,4], and especially in applications where cost is a relevant constraint, such as medium voltage distribution systems, a Medium Frequency (MF) transformer is normally preferred.…”

A review of power converter topologies with medium/high frequency transformers for grid interconnection systems

“…Since, such a power converter has a large number of semiconductor devices [2], therefore without galvanic isolation, an occurrence of a fault can cause an excessive current flow through the semiconductor devices which U. Nasir, A. Costabeber and P. can possibly destroy expensive equipment on both the input and the output sides of the converter. Although the galvanic isolation can be provided by employing a line frequency transformer at the output of the power converter, but the transformer operating at line frequency is expensive, bulky and heavy [4], [5]. Hence, by employing the line frequency transformer with the converter, the idea to reduce overall size of the converter becomes vague.…”