A simple low-loss linear negative resistor emulator

This paper shows how to synthesize a single-quadrant linear negative resistor from a discontinuous-mode (DCM) flyback converter with a few passive components. Although the synthesis of negative resistors has been previously accomplished with op-amps, the circuit in this paper works at moderate power levels and is nearly lossless. Such a circuit has potential use in several applications, including increasing the capability of existing power supply systems or in filter design. The circuit is simple and low cost. A design procedure for this system is developed, small-signal dynamic models derived, and experimental verification presented.