Semiconductor component reduction in AC/DC converters with transmission lines

By replacing the power inductor in a traditional converter topology with a transmission line, new functions such as inverting and non-inverting output voltage polarity from the same converter will arise. In this paper, the proposed technology was investigated in an AC/DC converter where the traditional topology (diode bridge and secondary DC/DC converter) was replaced with a single converter with a transmission line as an energy storage device. The transmission line was realized with lumped elements and the major benefit was found to be a reduced number of semiconductors; the same functionality could be achieved with only half the original amount. Due to practical reasons, the operating principle was verified in a DC/AC-circuit which was simulated in LTspice. The simulations showed that a switch mode converter with transmission line is possible to use for the suggested application with a power stage efficiency of η_PwSt=87%. To verify the simulations, a prototype was built and tested which showed that the principle works in practice with a measured power stage efficiency of η_PwSt=85%.