High speed power factor controller

摘要

A microprocessor is coupled to sense the current and voltage in a power phase at a high sampling rate such as two hundred fifty-five (255) times per cycle, and to determine the power factor. The primary of a transformer is coupled across the power lines, and at least two capacitors, forming separate switching paths, are coupled to the secondary of the transformer. High speed switching circuitry under the control of the microprocessor alternately charges and discharges the capacitors, at varying frequencies, to alternately store energy from the power lines when the variable load is returning energy to the power lines, and to supply the stored energy back to the power lines when the variable load is absorbing energy from the power lines. This corrects the power factor since the frequency of the high speed switching circuitry is varied with the varying reactance of the load.