Harmonic blocking compensator with adaptive minimization of reactive and unbalanced currents

The paper presents a new method of adaptive compensation and harmonic suppression in distribution systems. The compensator integrates a harmonic blocking compensator with an adaptive balancing compensator resulting in a novel compensator. Such a compensator can be used for compensating reactive power, for symmetrizing supply currents, for protecting the distribution system against load generated current harmonics and, consequently, the voltage harmonic distortion caused by harmonic generating loads. A harmonic blocking compensator provides harmonic suppression while the adaptive balancing compensator, consisting of three thyristor-controlled susceptance circuits, provides the variable susceptances needed for reactive and unbalanced power compensation. The paper presents the operation principles of an adaptive harmonic blocking compensator and its design, as well as results of a computer simulation of such a compensator.