This paper proposes a notion of virtual isolation that uses capacitors instead of transformers. Unlikely in the magnetically isolated converter, capacitors create an electrical path connecting the primary and secondary sides. Consequentially, touch current and electromagnetic interference (EMI) are generated by the common-mode current through the path. In this paper, virtual isolation is defined as satisfying touch current and EMI regulations, just as electrical isolation does, despite its electrical path. With virtual isolation, high power density is achieved while ensuring human safety. The experimental results from a 40W converter prototype confirm the effectiveness of the proposed design.
