Voltage harvester for power distribution system devices
The present disclosure provides exemplary embodiments of voltage harvesting devices used in power distribution systems, and provides power distribution system architectures utilizing the voltage harvesting devices. Generally, the voltage harvesting devices transform distribution line AC voltages to produce a low wattage output for distribution system communication and control type devices. The voltage harvesting device can operate whether irrespective of the presence of load current.
1. A transformation circuit for harvesting power in power distribution systems, the transformation circuit comprising:
at least one first impedance component; and
at least one second impedance component comprising,
a first input for coupling to a loaded or unloaded source line voltage,
a second input for coupling to the at least one first impedance component, and
an output for coupling to a device,
wherein an AC voltage on the output of the second impedance component is a higher voltage than the loaded or unloaded source line voltage.
2. The transformation circuit according to claim 1 , wherein the first impedance component is coupled to actual ground.
3. The transformation circuit according to claim 2 , further comprising a first overvoltage disconnect component electrically coupled between the first input of the at least one second impedance component and actual ground.
4. The transformation circuit according to claim 3 , wherein the first overvoltage device comprises one or more daisy-chained bi-directional TVS diodes, FETs, or PTC fuses.
5. The transformation circuit according to claim 3 , further comprising a second overvoltage disconnect device electrically coupled across the output of the at least one second impedance component.
6. The transformation circuit according to claim 5 , wherein the second overvoltage device comprises one or more daisy-chained bi-directional TVS diodes, FETs, or PTC fuses.
7. The transformation circuit according to claim 1 , further comprising a converter electrically coupled to the output of the at least one second impedance component that converts the AC output voltage of the at least one second impedance component to a DC voltage.
8. The transformation circuit according to claim 1 , wherein the at least one second impedance component is a transformer.
9. The transformation circuit according to claim 1 , wherein the at least one first impedance component is a resistor.
10. The transformation circuit according to claim 1 , wherein the at least one first impedance component comprises a parallel resistor network.
11. The transformation circuit according to claim 1 , wherein the at least one first impedance component comprises two or more parallel resistors and a series resistor.
12. The transformation circuit according to claim 1 , wherein the output and the device both reference a floating ground of the loaded or unloaded source line voltage.
13. The transformation circuit according to claim 1 , wherein the at least one first impedance component comprises two or more resistors in series.
14. The transformation circuit according to claim 1 , wherein the first impedance component and the second impedance component are arranged as a voltage divider.
15. A transformation circuit for harvesting power in high voltage AC power distribution systems, the transformation circuit comprising:
a transformer comprising,
a primary side with a first input for electrical connection to a loaded or unloaded AC line voltage source, and a second input, and
a secondary side having a first output for electrical connection to a floating ground referenced to the loaded or unloaded source AC line voltage and a second output providing an AC voltage above a voltage of the loaded or unloaded AC line voltage source; and
at least one resistive element electrically connected between the second input of the transformer and actual ground.
16. The transformation circuit according to claim 15 , wherein the AC voltage provided by the second output of the transformer is in the range of about 25 VAC to 250 VAC relative to the loaded or unloaded AC line voltage source.
17. The transformation circuit according to claim 15 , further comprising at least one overvoltage disconnect provided between the first input of the transformer and the resistive element.
18. The transformation circuit according to claim 17 , wherein the at least one overvoltage disconnect comprises one or more daisy-chained bi-directional TVS diodes, FETs, or PTC fuses.
19. The transformation circuit according to claim 17 , further comprising at least one overvoltage disconnect provided between the first and second outputs of the transformer.
20. The transformation circuit according to claim 19 , wherein the at least one overvoltage disconnect comprises one or more daisy-chained bi-directional TVS diodes, FETs, or PTC fuses.