Impedance synthesis by inverter control for active loads in anti-islanding testbenches

This paper discusses the emulation of an active RLC load by means of an inverter. To this purpose, a suitable current control strategy is analyzed and developed. The limitations of this approach are explored, highlighting the requirements of the adopted regulator in order to avoid instability issues. The proposed analysis and model of the controlled system are verified by means of simulations and experimental tests on a 15kVA prototype. The model is able to predict the presence of the resonant peaks closed to the current control bandwidth, thus giving useful guidelines to minimize such undesired effects. Finally, as a test case, the emulation of a resonant RLC load to be used in anti-islanding tests is considered.