A cost-effective DC/DC-converter with integrated UPS-function

A new DC/DC power converter with an integrated UPS function is described. The solution has important advantages compared to other UPS approaches: minimized number of conversion stages; very high efficiency during battery operation; no interruption at line failure; small volume; and low cost. A conventional DC/DC power converter is supplemented by a second input winding of the power transformer, a second switch-circuit and a charge circuit. Only one control circuit for both inputs is necessary; the change from line to battery operation is natural. Simulation results show the function of the system