Patent ID: 7304872
Filing Date: 2007-12-04
Classification: H02M

Abstract:
1. A dropping impedance power supply operative from a high voltage AC power line, with the first input of the power supply connected to a first conductor held at potential V 1 , and the second input of the power supply connected to a second conductor held at potential V 2 , comprised of: a high voltage impedance string consisting of one or more series-connected electrical impedances, each said impedance consisting of a resistor in series with a capacitor, said high voltage impedance string connected in series with one or more power modules each generating a reduced output voltage suitable for providing electrical power to electronic equipment connected to said modules; said power module each comprised of more than one step-down transformers, the primary windings of which are connected in series with each other, with the two ends of the series-connected transformers constituting the two input terminals of the power module; a voltage limiting element connected in parallel with the primary winding of each series-connected transformer; and the secondary windings of the step-down transformers connected in parallel with each other so as to sum their output currents, with the two common secondary winding connections constituting the two output terminals of the power module.