Realization of loss-free resistive elements

The realization of loss-free elements with resistive I V characteristics is presented. The realization is achieved by controlling the parameters of loss-free two-ports that have a transformer or gyrator matrix. The power absorbed by the element is transferred to the source, so that, in principle, no losses occur. The use of such elements is expected to be of importance in power electronics, power conversion systems, gas discharge devices, control systems, robotics, and microwave circuits. Such an element was realized using a switched-mode circuit technique. It was applied to the stabilization of a gas laser system. The circuit replaced a conventional resistor that dissipated power up to 40 W. The replacement circuit dissipated only 10 W (equivalent to a conversion efficiency of 75%)