Connecting power plants to high voltage networks

Patent metadata

Field	Value
Publication number	US-2016149509-A1
Application number	US-201414550505-A
Country	US
Kind code	A1
Filing date	Nov 21, 2014
Priority date	Nov 21, 2014
Publication date	May 26, 2016
Grant date	—

Abstract

The invention relates to a Terminal (I) for electrical connection of an amount of electrical generators ( 1 ) to a high-voltage transmission network ( 3 ), the terminal (I) comprising connected in series in this order for each generator ( 1 ) assembly level (Li):
a start AC/DC converter ( 5 ) for rectification of the generator voltage(s); a series resonant converter ( 7 ) for galvanic isolation between the generator ( 1 ) and the high-voltage; a converter unit ( 9 ) for providing the high-voltage.

First claim

1 . Terminal (I) for electrical connection of an amount of electrical generators ( 1 ) to a high-voltage transmission network ( 3 ), the terminal (I) comprising connected in series in this order for each generator ( 1 ) assembly level (Li):
a start AC/DC converter ( 5 ) for rectification of the generator voltage(s); a series resonant converter ( 7 ) for galvanic isolation between the generator ( 1 ) and the high-voltage; a converter unit ( 9 ) for providing the high-voltage.

2 . Terminal (I) according to claim 1 ,
characterized by that the electrical generator(s) ( 1 ) is/are (a) wind power generator(s), the high-voltage transmission network ( 3 ) transmits direct-current and the terminal (I) comprising connected in series in this order for each generator ( 1 ) assembly level (Li): a start AC/DC converter ( 5 ) for rectification of the generator voltage(s); a boost converter ( 6 ) for increasing and adjusting the DC generator voltage(s); a series resonant converter ( 7 ) for galvanic isolation between the generator ( 1 ) and the high-voltage; an AC/DC converter unit ( 9 b ) for providing the high-voltage direct-current.

3 . Terminal according to claim 2 ,
characterized by that the terminal (I) comprises a plurality of generator assembly levels (L 1 . . . Ln), whereby each AC/DC converter unit is a voltage multiplier ( 9 c ), in particular a Villard cascade voltage multiplier, their direct voltages are electrically connected in series into the high-voltage.

4 . Terminal according to claim 2 ,
characterized by that the terminal (I) comprises a plurality of generator assembly levels (L 1 . . . Ln), whereby all their series resonant converters ( 7 ) are inductively coupled by a common transformer unit ( 11 ) to a common AC/DC converter unit ( 9 d ) for providing the high-voltage direct-current.

5 . Terminal according to claim 4 ,
characterized by that the common transformer unit ( 11 ) comprises a primary coil ( 13 ) for each series resonant converter ( 7 ) and a single common secondary coil ( 15 ), thus adding primary voltages in series and transforming them into the high-voltage.

6 . Terminal according to claim 5 ,
characterized by that the single common secondary coil ( 15 ) is centrally tapped, thus transforming the added primary voltages into a positive and/or a negative high-voltage.

7 . Terminal according to claim 4 ,
characterized by that the common transformer unit ( 11 ) comprises a primary coil ( 13 ) and a secondary coil ( 17 ) for each series resonant converter ( 7 ), thus transforming the primary voltages into the secondary voltages and adding them in series within the common AC/DC converter unit ( 9 d ) for providing the high-voltage direct-current.

8 . Terminal according to claim 1 ,
characterized by that each generator assembly level (Li) is formed as a three-phase system.

9 . Terminal according to claim 8 ,
characterized by that within each generator assembly level (Li) for transforming a primary three-coil-system and a secondary three-coil-system is formed.

10 . Terminal according to claim 1 ,
characterized by that each series resonant converter ( 7 ) for each phase consists of an electrical clock frequency-switch-, in particular MOSFET- or JZF- or IGBT-, H-bridge ( 19 ) with a shunt arm comprising a capacity ( 21 ) and a bridge transformer ( 23 ).

11 . Terminal according to claim 10 ,
characterized by that each series resonant converter ( 7 ) for each phase comprises an amount of electrical clock frequency-switch-H-bridges ( 19 ) electrically connected in parallel to each other.

12 . Terminal according to claim 11 ,
characterized by that for each shunt arm the capacity ( 21 ) and the primary bridge transformer coil ( 25 ) are formed, whereby the AC power of each electrical clock frequency-switch-H-bridge ( 19 ) is inductively added in series by a single common secondary bridge transformer coil ( 27 ) formed for all parallel electrical clock frequency-switch-H-bridges ( 19 ).

13 . A method for controlling a terminal for electrical connection of at least one electrical generator to a high-voltage transmission network, the terminal having connected in series in order for each generator assembly level: a start AC/DC converter for rectification of generator voltage; a series resonant converter, including an electrical clock frequency-switch-H-bridge, for galvanic isolation between the generator and the high-voltage transmission network; and a converter unit for providing high-voltage, said method comprising:
adjusting the high-voltage and controlling a power output by setting at least one clock frequency, in particular up to 250 KHz or between 20 and 30 MHz, for the electrical clock frequency-switch-H-bridge of each series resonant converter.

14 . Method for controlling a terminal according to claim 13 ,
characterized by phase shifted controlling of each electrical frequency-switch-H-bridge ( 19 ) connected in parallel to other electrical frequency-switch-H-bridge(s) ( 19 ).

15 . Method for controlling a terminal according to claim 13 ,
characterized by individual adjustment of the resonance frequency of each electrical frequency-switch-H-bridge ( 19 ).

16 . Method for controlling a terminal according to claim 13 ,
characterized by (M 2 ) setting of the high-voltage using the boost converter(s) ( 6 ).

17 . Method for controlling a terminal according to claim 13 ,
characterized by in case the terminal (I) comprises a plurality of generator assembly levels (L 1 . . . Ln) an (M 3 ) equalizing of the DC generator voltages of different generator assembly levels using the boost converters ( 6 ) is performed.

18 . Method for controlling a terminal according to one of the precedent claims 13 ,
characterized by for each three-phase-system each common transformer core ( 29 ) is minimized in mass.

Assignees

• Siemens Ag

Inventors

• Hergt Martin
• Kurthakoti Chandrashekhara Divya
• Schacherer Christian

Classifications

• H02J1/00

  Circuit arrangements for DC mains or DC distribution networks · CPC title

• H02M7/04 Primary

  by static converters · CPC title

• H02M1/0077

  Plural converter units whose outputs are connected in series · CPC title

• H02M1/007

  Plural converter units in cascade (push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826) · CPC title

• Y02B70/10

  Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes · CPC title