This article studies a hybrid nonlinear vibration absorber. It consists of a passive part (a Nonlinear Energy Sink) and an active part (electromagnetic transducer). This work aims to tune the internal properties of the NES in real time, such that the activation threshold and effective energy pumping mechanism are maintained under varying operating conditions. To this end, numerical tools are developed for the design of suitable control laws which are then validated on a structure with varying parameters.