A Single-switched Resonant DC Link (SRDCL) converter is presented for a
parallel resonant network with a single auxiliary power device for low
conduction loss in single or poly-phase inverter and converter
applications. The resonant network with an auxiliary power device is
activated when the status of power devices coupled to the DC link
changes. The resonant network forces the DC link voltage to drop to zero
before any of the power devices coupled to the DC link are turned on. The
auxiliary switch is also turned on with a Zero-Voltage Switching
condition. Therefore, the switching losses caused in all power devices
can be effectively eliminated. There is no severe conduction loss in the
auxiliary power device because the resonant circuit is not activated if
there is no change of status in the power devices coupled to the DC link.