Compensating reactive power in electrical supply network - using choke coil in series with anti-parallel thyristor switch across phase and neutral lines

摘要

A choke coil (2), serving as an electrical energy store is connected in series with an AC switch (3) employing anti-parallel thyristors. The switching in and switching out of the choke coil (2) is used to compensate both positive and negative phase angles, the switching effected between each zero transition and the subsequent positive or negative voltage peak for inductive blind load compensation and between a positive or negative voltage peak and the subsequent zero transition for capacitive blind load compensation. An over-voltage protection device (4) is connected across the coil (2) for damping the switching over-voltages the corresp. energy fed back to the supply network via a DC/AC converter (5). ADVANTAGE - Reduced current harmonics.