High voltage direct current transmission and distribution system

Patent metadata

Field	Value
Publication number	US-9270119-B2
Application number	US-201313901770-A
Country	US
Kind code	B2
Filing date	May 24, 2013
Priority date	May 24, 2013
Publication date	Feb 23, 2016
Grant date	Feb 23, 2016

Abstract

A direct current to alternating current inverter sub-system is for a HVDC distribution system. The DC to AC inverter sub-system includes an enclosure and a DC to DC galvanically isolated buck converter having a DC input electrically connectable to a HVDC cable and a DC output. A DC to AC inverter includes a DC input electrically connected to the DC output of the DC to DC galvanically isolated buck converter and an AC output electrically connectable to an AC transmission line. The DC to AC inverter is mounted in an enclosure with the DC to DC galvanically isolated buck converter, in order that the DC output of the DC to DC galvanically isolated buck converter is directly electrically connected within the enclosure to the DC input of the DC to AC inverter.

First claim

What is claimed is:

1. A high voltage direct current transmission and distribution system comprising:
an alternating current to direct current converter including an alternating current input and a direct current output;
a first high voltage direct current cable including a first end electrically connected to the direct current output of said alternating current to direct current converter and an opposite second end; and
a distribution system comprising:
a number of high voltage direct current circuit breakers, each of said number of high voltage direct current circuit breakers including a first portion electrically connected to the opposite second end of said first high voltage direct current cable and a second portion;
a number of second high voltage direct current cables, each of said number of second high voltage direct current cables including a first end electrically connected to the second portion of a corresponding one of said number of high voltage direct current circuit breakers and an opposite second end;
a number of galvanically isolated direct current to direct current converters, each of said number of galvanically isolated direct current to direct current converters including a direct current input electrically connected to the opposite second end of a corresponding one of said number of second high voltage direct current cables and a direct current output;
a number of direct current to alternating current voltage source inverters, each of said number of direct current to alternating current voltage source inverters including a direct current input electrically connected to the direct current output of a corresponding one of said number of galvanically isolated direct current to direct current converters and an alternating current output;
a number of alternating current transmission lines, each of said number of alternating current transmission lines including a first end electrically connected to the alternating current output of a corresponding one of said number of direct current to alternating current voltage source inverters and an opposite second end; and
a number of alternating current loads, each of said number of alternating current loads electrically connected to the opposite second end of a corresponding one of said number of alternating current transmission lines,
wherein each of said number of direct current to alternating current voltage source inverters is mounted in an enclosure with a corresponding one of said number of galvanically isolated direct current to direct current converters, in order that the direct current output of the last said corresponding one of said number of galvanically isolated direct current to direct current converters is directly electrically connected within the enclosure to the direct current input of a corresponding one of said number of direct current to alternating current voltage source inverters.

2. The high voltage direct current transmission and distribution system of claim 1 wherein said alternating current to direct current converter is above ground, subsea, or below ground.

3. The high voltage direct current transmission and distribution system of claim 1 wherein said first high voltage direct current cable is partially above ground and partially below ground, partially above sea and partially subsea, entirely subsea, or entirely below ground.

4. The high voltage direct current transmission and distribution system of claim 1 wherein said number of high voltage direct current circuit breakers, said number of second high voltage direct current cables, said number of galvanically isolated direct current to direct current converters, said number of direct current to alternating current voltage source inverters, said enclosure, said number of alternating current transmission lines, and said number of alternating current loads are subsea or below ground.

5. The high voltage direct current transmission and distribution system of claim 1 wherein the alternating current output of said number of direct current to alternating current voltage source inverters is a three-phase alternating current output.

6. The high voltage direct current transmission and distribution system of claim 5 wherein one of said number of alternating current loads is a three-phase alternating current motor.

7. The high voltage direct current transmission and distribution system of claim 1 wherein said alternating current to direct current converter comprises a plurality of alternating current to direct current converters electrically connected in series, in parallel, or in series and in parallel.

8. The high voltage direct current transmission and distribution system of claim 1 wherein said alternating current to direct current converter is an active converter structured to shut down responsive to a short circuit condition operatively associated with said first high voltage direct current cable.

9. The high voltage direct current transmission and distribution system of claim 1 wherein said alternating current to direct current converter is an active converter structured to ramp a direct current voltage at the direct current output thereof at a predetermined rate from zero volts to a high direct current voltage.

10. The high voltage direct current transmission and distribution system of claim 1 wherein said first high voltage direct current cable includes a plurality of conductors selected from the group consisting of two power conductors for a bipolar transmission line, and one power conductor for a unipolar transmission line.

11. The high voltage direct current transmission and distribution system of claim 1 wherein each of said number of high voltage direct current circuit breakers comprises the series combination of an electromechanical isolation switch and a solid-state switch, the series combination being electrically connected between the first portion and the second portion of said each of said number of high voltage direct current circuit breakers.

12. The high voltage direct current transmission and distribution system of claim 11 wherein when both of said electromechanical isolation switch and said solid-state switch are closed, the second portion charges the corresponding one of said number of second high voltage direct current cables to or toward a high direct current voltage.

13. The high voltage direct current transmission and distribution system of claim 11 wherein each of said number of high voltage direct current circuit breakers further comprises a modulation element structured to repetitively turn on and turn off said solid-state switch when said electromechanical isolation switch is closed, in order to control charging of a corresponding one of said number of second high voltage direct current cables from zero volts to a high direct current voltage from the first portion of said each of said number of high voltage direct current circuit breakers.

14. The high voltage direct current transmission and distribution system of claim 13 wherein said modulation element is structured to ramp a direct current voltage of the second portion of said each of said number of high voltage direct current circuit breakers.

15. The high voltage direct current transmission and distribution system of claim 13 wherein said each of said number of high voltage direct current circuit breakers further comprises a trip mechanism structured to detect a fault downstream of the second portion thereof responsive to a failure to charge the corresponding one of said number of second high voltage direct current cables.

16. The high voltage direct current transmission and distr

Assignees

• Eaton Corp

Inventors

• Broussard Harry
• Nojima Geraldo

Classifications

• H02J3/36 Primary

  Arrangements for transfer of electric power between AC networks via high-voltage DC [HVDC] links; Arrangements for transfer of electric power between generators and networks via HVDC links · CPC title

• Y02E60/60

  Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD] · CPC title

• H01H9/548

  Electromechanical and static switch connected in series · CPC title

• H02J2003/365

  Reducing harmonics or oscillations in HVDC · CPC title

• H01H33/596

  for interrupting DC · CPC title