Synthesis of controlled reactances using VSC converters

This work presents a review of the main techniques for synthesizing positive and negative inductance using power electronics: VAPAR (variable active-passive reactance), BVI (bootstrap variable inductance), AVI (active variable inductance) and DRS (direct reactance synthesis). Based on this review a new topology for synthesizing a fundamental frequency variable reactances based on synchronism circuits (PLL - phase-locked loop) is presented. The main advantage of this new technique is that the control signals are immune to the noise from the grid. Some simulation results, using PSCAD/EMTDC, are presented for the proposed circuit.