Some Properties of a Rectifier Circuit With Sinusoidal Supply Voltage and Resistive Load

The power factor of a rectifier circuit with resistive load and sinusoidal terminal voltage can be represented by the product of two analytical components known as the distortion factor and the displacement factor. The distortion factor, caused by load impedance non-linearity, and the displacement factor, caused by current delay due to thyristor triggering, are both affected by terminal capacitance. The displacement factor is not associated with energy storage but may nevertheless be improved by power factor correction capacitors. At low firing-angles the degree of power factor improvement realisable is of the order a few per cent but at high firing angles the power factor is more than doubled.