Power supply for electronic circuits at high-voltage potential

Claim 2

Power supply apparatus for supplying power from a low-voltage reference potential to an electronic circuit operable with respect to a high-voltage potential such as an electronic circuit for detecting the current in a high-voltage conductor and the like, the electronic circuit being connected to an associated transformer for receiving electric energy, the apparatus comprising a power oscillator operable with respect to the low-voltage potential and having an output transformer, current path means for conducting electric power from said output transformer of said oscillator at low-voltage potential to the associated transformer connected to the electronic circuit, and power source means for supplying electric power to said power oscillator independently of the value of the electrical energy at the high-voltage potential.

Claim 3

The power supply apparatus of claim 1, said current path means comprising an input winding forming part of the associated transformer connected to the electronic circuit, an impedance arrangement serially connected to said input winding, and an output winding forming part of said output transformer of said power oscillator, said output winding being connected to the serial combination of said input winding and said impedance arrangement.

Claim 4

Power supply apparatus for supplying power from a low-voltage reference potential to an electronic circuit operable with respect to a high-voltage potential such as an electronic circuit for detecting the current in a high-voltage conductor and the like, the apparatus comprising a power oscillator operable with respect to the low-voltage reference potential and having an output transformer, said transformer having a secondary winding, an associated transformer at the high-voltage potential, said associated transformer having a primary winding and having a secondary winding connectable to the electronic circuit, an impedance arrangement seriallly connected to said primary winding of said associated transformer and to said secondary winding of said output transformer so as to conjointly define a series current path therewith extending between the high-voltage potential and the low-voltage reference potential, and power source means for supplying electric power to said power oscillator independently of the value of energy at the high-voltage potential whereby said power oscillator in turn supplies power through said output transformer, said impedance arrangement, and said associated transformer to the electronic circuit independent of the voltage and current conditions on the high-voltage current conductor.

Claim 5

Power supply apparatus for supplying power from a low-voltage reference potential to an electronic circuit operable with respect to a high-voltage potential such as an electronic circuit for detecting the current in a high-voltage conductor and the like, the apparatus comprising a power oscillator operable with respect to the low-voltage reference potential and having an output transformer, said transformer having a secondary winding, an associated transformer at the high-voltage potential, said associated transformer having a primary winding and having a secondary winding connectable to the electronic circuit, an impedance arrangement seriallly connected to said primary winding of said associated transformer and to said secondary winding of said output transformer so as to conjointly define a series current path therewith extending between the high-voltage potential and the low-voltage reference potential, and power source means for supplying electric power to said power oscillator independently of the value of energy at the high-voltage potential whereby said power oscillator in turn supplies power through said output transformer, said impedance arrangement, and said associated transformer to the electronic circuit independent of the voltage and current conditions on the high-voltage current conductor.

Claim 6

The power supply of claim 3, said power oscillator being configured to generate a current having a frequency of 20 kHz and higher.

Claim 7

The power supply of claim 4, said power oscillator being configured to generate a current having a frequency in range from 20 kHz to 75 kHz.

Claim 8

The power supply of claim 3, said impedance arrangement comprising a capacitor arranged intermediate said secondary winding of said output transformer and said primary winding of said associated transformer.

Claim 9

The power supply apparatus of claim 6, said current path means comprising an additional capacitor connected in series with said secondary winding of said output transformer so as to define a series circuit including said additional capacitor, said secondary winding, said first-mentioned capacitor and said primary winding, said first-mentioned capacitor and said additional capacitor being upper potential and lower potential capacitors respectively, said upper potential capacitor and said lower potential capacitor defining a capacitive divider.

Claim 10

The power supply apparatus of claim 7 wherein provision is made for making voltage measurements, said lower potential capacitor having terminals at respective ends thereof, and a measuring amplifier connected to said terminals, said amplifier in turn having output terminals to which a voltage measuring instrument is connectable.

Claim 11

The power supply apparatus of claim 7 comprising a structure for containing said power oscillator and said lower potential capacitor, said lower potential capacitor having terminals at respective ends thereof, said terminals being brought to the outside of said structure for facilitating access thereto.

Claim 12

The power supply apparatus of claim 7, said associated transformer, said oscillator, said capacitors, and the electronic circuit at high-voltage potential being configured to form a composite unit.

Claim 13

The power supply apparatus of claim 3 comprising a capacitive divider connected in parallel with said current path means and between the low-voltage potential and the high-voltage potential, said capacitive divider comprising an upper potential capacitor, and a lower potential capacitor connected in series with said upper potential capacitor.

Claim 14

The power supply apparatus of claim 3 wherein said power oscillator has an output circuit connecting said oscillator with the primary of said output transformer, and wherein said apparatus comprises circuit means connected in said output circuit for monitoring the current generated by said oscillator to generate a signal in response to a drop in current below a minimal value required by the electronic circuit at the high-voltage potential.

Claim 15

The power supply apparatus of claim 3, said current path means comprising limit circuit means connected to the circuit containing said serial combination and said secondary winding of said output transformer for generating a turn-off signal for said oscillator in response to an increase in the current in said circuit above a minimal value required by the electronic circuit at the high-voltage potential.

Claim 16

The power supply apparatus of claim 3, said apparatus and the electronic circuit at high-voltage potential being configured to form a composite unit.