ELECTRICAL NETWORK

Abstract

An electrical network includes feed-in means, loads, and a distribution network located therebetween which includes at least one dynamic isolator and busbars. The feed-in means and the loads together with associated busbars are disposed in groups which can be electrically interconnected or disconnected by the at least one dynamic isolator. The at least one dynamic isolator monitors the voltage on the busbars adjacent thereto for a voltage difference. In a normal state without a voltage difference, the at least one dynamic isolator electrically disconnects the groups from one another, and in the event of a voltage difference between the busbars adjacent thereto, the at least one dynamic isolator electrically connects the groups to one another.

Claims

1-11. (canceled)

12. An electrical network, comprising: feed-in devices; loads; and a distribution network disposed between said feed-in devices and said loads, said distribution network including at least one dynamic isolator and busbars; said feed-in devices, said loads and said busbars being disposed in groups configured to be electrically connected to one another or disconnected from one another by said at least one dynamic isolator; said at least one dynamic isolator monitoring voltage on adjacent busbars for a voltage difference; in a normal state without the voltage difference, said at least one dynamic isolator electrically disconnecting said groups from one another; and upon the voltage difference occurring between adjacent said busbars, said at least one dynamic isolator electrically connecting said groups to one another.

13. The electrical network according to claim 12, wherein said at least one dynamic isolator electrically connects said groups to one another when the voltage difference is greater than a predefined voltage difference threshold value.

14. The electrical network according to claim 12, wherein upon a voltage difference occurring between said adjacent busbars, said at least one dynamic isolator electrically disconnects said groups from one another again after connection, upon a fault occurring in one of said adjacent groups.

15. The electrical network according to claim 14, wherein said at least one dynamic isolator repeatedly determines, in a time interval, a presence of a fault in one of said adjacent groups.

16. The electrical network according to claim 14, wherein said at least one dynamic isolator assumes a fault in one of said adjacent groups upon a change in the voltage difference between said adjacent busbars exceeding a voltage change threshold value.

17. The electrical network according to claim 14, wherein said at least one dynamic isolator assumes a fault in one of said adjacent groups upon a change in current through said at least one dynamic isolator exceeding a current change threshold value.

18. The electrical network according to claim 12, wherein said at least one dynamic isolator disconnects said groups provided that no voltage difference arises across said at least one dynamic isolator being associated with a flow of power through said at least one dynamic isolator and an imbalance between said feed-in devices and said loads in a group.

19. The electrical network according to claim 12, wherein said at least one dynamic isolator monitors current for overload and said at least one dynamic isolator is protected in an event of an overload.

20. The electrical network according to claim 12, wherein the electrical network is operated with direct current or alternating current.

21. The electrical network according to claim 12, wherein said at least one dynamic isolator includes two anti-parallel solid-state transformers or active front ends.

22. The electrical network according to claim 12, which further comprises at least one electromechanical switch configured to disconnect one of said feed-in devices or one of said loads in an event of a fault.

Description

[0028] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

[0029] FIG. 1: shows a DC network having feed-in means and loads and dynamic isolators;

[0030] FIGS. 2A and 2B: show dynamic isolators for DC operation;

[0031] FIG. 3: shows an AC network having feed-in means and loads and dynamic isolators; and

[0032] FIGS. 4A and 4B: show dynamic isolators for AC operation.

[0033] FIG. 1 shows an electrical network 1000 according to the invention. This electrical network 1000 comprises feed-in means 1010; 1011; 1012; 1013, loads 1050; 1051; 1052; 1053 and a distribution network 2000 arranged therebetween. This distribution network 2000 comprises at least one dynamic isolator 2010; 2011 and busbars 200, 200', 200''. The feed-in means 1010; 1011; 1012; 1013 and the loads 1050; 1051; 1052; 1053, together with associated busbars 200, 200', 200'', are arranged in groups, wherein these groups can be electrically connected to one another or disconnected from one another by means of the dynamic isolators 2010; 2011.

[0034] In accordance with FIG. 1, the feed-in means 1010 and the load 1050 form a first group on the busbar 200, the feed-in means 1011 and 1012 and the loads 1051 and 1052 form a second group together with the busbar 200' and the feed-in means 1013 and the load 1053 form a third group together with the busbar 200''.

[0035] The busbar 200 of the first group is connected to the busbar 200' of the second group by means of a first dynamic isolator 2010, with the result that the first dynamic isolator 2010 can electrically connect the busbars 200, 200' to one another or disconnect them from one another. The same applies to the second dynamic isolator 2011 that is arranged between the busbar 200' of the second group and the busbar 200'' of the third group and that can electrically connect said busbars to one another or disconnect them from one another.

[0036] The at least one dynamic isolator 2011; 2012 monitors the voltage on the busbars adjacent thereto for a voltage difference. Accordingly, the first dynamic isolator 2010 monitors the voltage difference from the busbar 200 of the first group to the busbar 200' of the second group, and the second dynamic isolator 2011 monitors the voltage difference from the busbar 200' of the second group to the busbar 200'' of the third group.

[0037] In the normal state, which means that no voltage difference is detected by the dynamic isolator 2010; 2011 during monitoring, the at least one dynamic isolator 2010; 2011 electrically disconnects the groups from one another. By way of example, the first dynamic isolator 2010 would electrically disconnect the first group from the second group upon monitoring the busbars 200 and 200' without a voltage difference. The voltage on the busbars 200 and 200' could be 650 V in each case, for example, meaning that the voltage difference would be 0 V.

[0038] If a voltage difference between adjacent busbars 200; 200'; 200'' is detected by the at least one dynamic isolator 2010; 2011; 2012, the groups are electrically connected to one another. If there is a dip in the voltage on a busbar 200, 200', 200'', the at least one dynamic isolator 2010; 2011; 2012 in the distribution network 2000 ensures that adjacent groups are electrically connected to one another, and voltage dips can therefore be compensated for.

[0039] The voltage on the busbars 200 and 200' could be 650 V and 645 V, for example, meaning that the voltage difference would be 5 V and these two groups are connected to one another. Upon aligning the voltages on the busbars 200 and 200', for example to 650 V and 649 V, these two groups would be disconnected from one another again.

[0040] Provision can be made for the at least one dynamic isolator 2010; 2011; 2012 to electrically connect the groups to one another if the voltage difference is greater than a predefined voltage difference threshold value. By way of example, this voltage difference threshold value could be 5 V.

[0041] Provision can furthermore be made, if there is a voltage difference between the busbars 200, 200', 200'' adjacent thereto, for the at least one dynamic isolator 2010; 2011; 2012 to electrically disconnect the groups from one another again after connection if there is a fault in one of the adjacent groups. Provision can be made here for it to be repeatedly determined, in a time interval Δt, whether there is a fault in one of the adjacent groups.

[0042] A fault in one of the adjacent groups can be assumed if the change in the voltage difference between the adjacent busbars 200, 200', 200'' exceeds a voltage change threshold value. Likewise, a fault in one of the adjacent groups can be assumed if a change in current through the at least one dynamic isolator 2010; 2011; 2012 exceeds a current change threshold value.

[0043] The dynamic isolator 2010; 2011; 2012 can disconnect the groups provided that no voltage difference arises across the dynamic isolator 2010; 2011; 2012 that is associated with a flow of power through the dynamic isolator 2010; 2011; 2012 and an imbalance between feed-in means 1010; 1011; 1012; 1013 and loads 1050; 1051; 1052, 1053 in a group.

[0044] Provision can additionally be made, in the case of the at least one dynamic isolator 2010; 2011; 2012, for the current to be monitored for overload and the at least one dynamic isolator 2010; 2011; 2012 to be protected in the event of overload.

[0045] The electrical network 1000 according to the invention can be operated with direct current or alternating current. The exemplary embodiment in FIG. 1 is a typical example of an electrical network 1000 that is operated with direct current. FIG. 3 shows an electrical network 1000 that is operated with alternating current.

[0046] In accordance with FIG. 3, the network 1000 comprises feed-in means 1010; 1011; 1012 and loads 1050; 1051; 1052. Dynamic isolators 2010; 2011; 2012 can segment the busbar 200 into three groups, with a first group comprising the feed-in means 1010 and the load 1050, a second group having the feed-in means 1011 and the load 1051 and a third group having the feed-in means 1012 and the load 1052.

[0047] In this case too, the dynamic isolators 2010; 2011; 2012 monitor the voltage on the adjacent busbars 200 for a voltage difference. In the normal state without a voltage difference, the dynamic isolators 2010; 2011; 2012 electrically disconnect the three groups from one another. If a voltage difference between adjacent busbars 200 of the three dynamic isolators 2010; 2011; 2012 arises, the respective dynamic isolator 2010; 2011; 2012 electrically connects the groups to one another.

[0048] In the first exemplary embodiment for operating the electrical network 1000 according to the invention with direct current in accordance with FIG. 1, electromechanical switches 2020; 2021; 2022; 2023; 2024; 2025; 2026; 2027 are furthermore provided to disconnect the feed-in means 1010; 1011; 1012; 1013 or the loads 1050; 1051; 1052, 1053 in the event of a fault.

[0049] In the first group, the electromechanical switch 2020 is provided to disconnect the feed-in means 2010 from the busbar 200 in the event of a fault. Furthermore, the electromechanical switch 2021 is provided to disconnect the load 1050 from the busbar 200 in the event of a fault. In the topology of FIG. 3, electromechanical switches 2020; 2021; 2022 are also provided that can electrically disconnect the feed-in means 1010; 1011; 1012 or the loads 1050; 1051; 1052 from the busbar.

[0050] FIGS. 2A and 2B specify configurations of a dynamic isolator 2010 in a DC network. Two anti-parallel solid-state transformers (SSTs) are used in FIG. 2A. These comprise a DC-AC converter 20, a high-frequency transformer 30 and an AC-DC converter 21 in series, and a DC-AC converter 23, a transformer 31 and an AC-DC converter 22 for the parallel return path.

[0051] FIG. 2B shows a dynamic isolator 2010 that comprises a first active front end (AFE) 24, a transformer 32 and a further active front end (AFE) 25.

[0052] FIGS. 4A and 4B show exemplary embodiments of a dynamic isolator 2010 for an electrical network 1000 that is operated with alternating current. In FIG. 4A there are therefore, in series, an AC-DC converter 40 for the system frequency, a high-frequency inverter 41, a transformer 50, an AC-DC converter 42 and a DC-AC converter 43 for the system frequency. An AC-DC converter 47, a high-frequency inverter 46, a transformer 51, an AC-DC converter 45 and a DC-AC converter 44 are correspondingly provided for the parallel return path.

[0053] In the exemplary embodiment in FIG. 4B, the dynamic isolator 2010 comprises a series circuit comprising a first, bidirectional AC-AC cycloconverter 48, a transformer 52 and a second, bidirectional AC-AC cycloconverter 49.