Transient free solid state automatic power factor correction

A transient free automatic power correction factor device for a multiphase alternating current source having a plurality of power lines which comprises:

• first means for detecting the current of each phase of the power lines of the alternating current source;
• second means for detecting the voltage of each phase of the power lines of the alternating current source;
• third means, responsive to said first means and said second means, for providing a count indicating the phase difference between current and voltage and for converting the count into a plurality of time dependent signals;
• microprocessor means, responsive to said third means, for executing instructions for converting the time dependent signals into degrees, for converting the degrees into a cosine value, to provide a power factor value signal;
• a plurality of banks of delta connected capacitors responsive to switching signals for adding or removing capacitance to or from the power lines of the alternating current source in response to the switching signals;
• and
• solid state switching means responsive to said power factor value signal for supplying said switching signals to said capacitors when, for any voltage, said voltage on said capacitors equals said voltage on the associated power line, whereby banks of capacitors can be added or subtracted at any time without creating any current surge or electrical transient.