CN100416969C

CN100416969C - Power supply system for island networks

Info

Publication number: CN100416969C
Application number: CNB038104067A
Authority: CN
Inventors: 维芒德·卡斯塔德
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 2002-05-08
Filing date: 2003-04-30
Publication date: 2008-09-03
Anticipated expiration: 2023-04-30
Also published as: CN1653667A; RU2004135822A; KR101027301B1; KR20040106492A; WO2003096511A1; JP3987529B2; RU2318283C2; NO20045340L; JP2005525074A; DE10220738A1; NO328312B1; AU2003232617A1

Abstract

The invention relates to a power supply system for island networks, particularly on oil drilling platforms or boats. Said power supply system comprises at least one generator (3) and at least two three-phase AC systems (1a, 1b). The generator (3) is provided with at least two three-phase coiling systems, whereby the phase-displaced three-phase AC systems (1a, 1b) in which the coiling systems of the generator (3) are three-dimensionally disposed according to the phase displacement of the three-phase AC systems (1a, 1b) are fed without or essentially without using current-converting transformers. The two three-phase AC systems (1a, 1b) jointly form the primary system (1) while feeding a secondary three-phase AC system (2) by means of a transformer device (4). The inventive power supply system is compact and has a reduced weight, which is particularly important for island systems.

Description

Power supply system for island network

Technical Field

The invention relates to a power supply system for an island network (Inselnetze), wherein the power supply system has at least one generator and at least two three-phase current systems.

Background

A power supply system for an island network is understood to be an overall energy system, i.e. an energy system in which electrical energy is generated, transmitted and finally converted into other forms of energy. This system is limited in space in terms of its volume and is not comparable to a land-based power supply system. Such systems are particularly useful in marine-related and/or mobile installations. For example on ships and other marine tools, on drilling platforms or other isolated, particularly marine-related, technical installations with energy requirements.

Depending on the implementation of the power supply system, there are usually at least two electrically phase-shifted three-phase current systems which are driven by means of parallel-connected converters to pass electrical energy. Current and voltage harmonics are induced by the phase shift of a three-phase current system. The phase shift of such three-phase current systems is currently produced by means of current transformers (stromerizers-transformers), wherein the phase shift of the three-phase current system is achieved by a corresponding selection of the circuit groups.

In the above-described power supply systems for island networks, the high weight of the system components employed brings with it the problem of gravity, particularly when at sea. Therefore, different solutions are currently available which attempt to optimize the devices belonging to the system in terms of weight, such as current transformers and converters.

Disclosure of Invention

The object of the present invention is to provide a power supply system for an island network with at least one generator and at least two three-phase current systems, which further improves the above-mentioned problems, among other things.

According to the invention, the above object is achieved in that the generator of the power supply system has two three-phase coil systems which are respectively associated with the three-phase current systems, wherein a voltage is induced in the coil systems, and the coil systems of the generator are spatially arranged such that the voltages of the two three-phase current systems are electrically phase-shifted with respect to one another. The power supply system has a primary system and a secondary three-phase current system, wherein the primary system is formed by the two three-phase current systems, is coupled to the secondary three-phase current system, and is coupled to a load.

Thus, according to the invention, the current transformers for generating the two three-phase current systems can be completely or at least largely dispensed with, so that considerable advantages are achieved in terms of weight and cost, and space is also saved.

Preferably, the electrical phase shift between the three-phase current systems in the primary system is 30 °. This phase shift is particularly advantageous for reducing current and voltage harmonics, which are supplied by means of parallel-connected converters and are optionally connected in the further three-phase current system.

Preferably, the coil system of the generator is mounted in the groove in such a way that the short-circuit current occurring is minimized. In this way, the undesirable energy input in the motor by the magnetic coupling on the stator side of the coil system can be significantly reduced.

Suitably, a load is connected to the three-phase current system of the two primary systems. This approach is just as useful to prevent loss of redundancy in the system for multiples with more than two or two three-phase current systems.

Advantageously, the power supply system has a primary system and a secondary three-phase current system, wherein the primary system is formed by two three-phase current systems and is coupled to the secondary three-phase current system. In this way, different devices in different voltage ranges can be applied to the circuit and/or the current transformer in the primary and secondary systems. The voltage range is preferably determined in each case by the load to be supplied with energy. This gives the advantage of a cost price as a whole, since more cost-effective means can be used for the low-pressure range, if necessary.

Preferably, the secondary three-phase current system is coupled to another generator. Hereby it is achieved that the load can also be supplied on the primary or secondary system in case of a fault in the other system while generating energy.

The coupling between the primary system and the secondary three-phase current system is preferably implemented in such a way that the energy generated by means of a generator coupled to the secondary three-phase current system can be supplied to the primary system. In this way, the generator connected to the secondary system can be used to supply the load connected to the primary system also in an emergency.

Drawings

Embodiments of the present invention and other advantages are further described below with reference to the accompanying drawings. Wherein,

fig. 1 shows a schematic diagram of an example of a power supply system for an island network according to the invention;

FIG. 2 shows a schematic diagram of an example of a power supply system with a load at a primary system, in accordance with the present invention;

FIG. 3 shows an example of a transformer arrangement for coupling a primary system and a secondary system;

fig. 4 shows an example of a transformer arrangement for coupling a primary system and a secondary system.

Detailed Description

Fig. 1 shows a schematic illustration of a power supply system for an island network according to the invention. The generator 3 connected to the two three-phase

current systems

1a, 1b generates energy, for example, by burning diesel fuel. The generator 3 has two three-phase coil systems, which are each associated with a three-phase

current system

1a, 1b, wherein a voltage is induced in the coil systems, and the coil systems are spatially arranged in the generator 3 in such a way that the voltages of the two three-phase

current systems

1a, 1b are electrically phase-shifted relative to one another. As a result, the current transformers for generating the two three-phase current systems can be completely or at least to the greatest possible extent dispensed with.

The two three-phase

current systems

1a, 1b together form a primary system 1. Preferably, the two three-phase

current systems

1a, 1b are electrically phase-shifted by 30 ° and the secondary three-phase current system 2 is supplied with power by means of at least one transformer device 4. Thereby, current and voltage harmonics are induced in the secondary three-phase current system 2. In the embodiment shown in fig. 1, the transformer arrangement 4 comprises two transformers connected in parallel.

A load, not shown, such as a motor or other drive device, is connected to both the primary system 1 and the secondary system 2. The generator 7 connected to the secondary system 2 can be used as a backup generator and ensures the power supply of the secondary system 2 and the primary system 1 when the main generator 3 is not operating.

Fig. 2 shows a schematic diagram of a further example of a power supply system according to the invention, wherein loads 6a, 6b are coupled to the primary system 1. The generator 3 is connected to two three-phase

current systems

1a, 1b, the two three-phase

current systems

1a, 1b preferably being electrically phase-shifted by 30 ° relative to one another. The two three-phase

current systems

1a, 1b form a primary system 1. The motors 6a, 6b are supplied with power by two

current transformers

5a, 5 b.

The primary system 1 is coupled to the secondary three-phase current system 2 by means of two transformer arrangements 4. Additional loads, not shown in the figures, may be attached to the motors 6a, 6b in connection with the primary system 1. Further loads and at least one generator, not shown in detail, are connected to the secondary three-phase current system 2 via

connections

8a, 8b, 8 c.

According to the exemplary embodiment shown in fig. 2, the design of the generator 3 ensures that, firstly, for suitable loads, such as the motors 6a, 6b, with the oil-extraction drilling rig, the load can be distributed uniformly on the stator-rotor side connected to the three-phase

current system

1a, 1 b. Wherein operation at the highest voltage amplitude is possible in the primary system 1.

The secondary three-phase current system 2 is coupled in a symmetrical manner to the primary system 1 via a transformer arrangement 4. The two transformer arrangements 4 have, for example, a delta connection on the primary side and a delta connection and a star connection on the secondary side.

Fig. 3 and 4 show further configurations of a transformer arrangement 4 for coupling a primary system 1 and a secondary system 2. In this case, the coil systems of the transformer device 4 are each associated with two primary three-phase

current systems

1a, 1b to the secondary three-phase current system 2 by means of

connectors

8a, 8b, 8 c. The transformer arrangement 4 shown in fig. 3 and 4 can be realized as an integrated transformer arrangement, i.e. it has only one coil system for each

connection

8a, 8b, 8c on the secondary side as schematically shown in the figures.

In the transformer arrangement 4 shown in fig. 3, the coil system is star-connected on the side of the secondary three-phase current system 2.

In the transformer device 4 shown in fig. 4, the coil systems are delta-connected on the side of the secondary three-phase current system 2.

Fig. 1 and 2 show a basic power supply system for an island network according to the invention. At least two such power supply systems may be coupled to each other. It is also possible to couple at least one power supply system according to the invention with an existing power supply system for island networks.

A power supply system consisting of a plurality of basic power supply systems as shown in fig. 1 and 2 can meet correspondingly high energy requirements, which can also be realized in that, in addition to one main generator 3, further main generators 3 are provided. The power supply system can also be designed such that it has a plurality of primary systems 1 for supplying one or more secondary systems 2. The power supply system can be designed such that one primary system 1 supplies one or more secondary three-phase current systems 2 and/or one secondary three-phase current system 2 is supplied via one or more primary systems 1.

The power supply system according to the invention is generally less expensive in terms of at least maintaining a uniform load, flexibility and capacity, and has a significantly lower weight than hitherto existing systems, and furthermore requires significantly less space than existing systems due to the elimination of the current transformer required for the two phase-shifted three-phase

current systems

1a, 1 b.

Claims

1. A power supply system for island networks with one generator (3) and two three-phase current systems (1a, 1b), characterized in that,

the generator (3) has two three-phase coil systems which are respectively associated with the three-phase current systems (1a, 1b), wherein a voltage is induced in the coil systems, and the coil systems of the generator (3) are spatially arranged such that the voltages of the two three-phase current systems (1a, 1b) are electrically shifted from one another;

the power supply system has a primary system (1) and a secondary three-phase current system (2), wherein the primary system (1) is formed by the two three-phase current systems (1a, 1b), is coupled to the secondary three-phase current system (2), and loads (6a, 6b) are coupled to the primary system (1).

2. Power supply system according to claim 1, characterized in that the electrical phase shift between the three-phase current systems (1a, 1b) in the primary system (1) is 30 °.

3. Power supply system according to claim 1 or 2, characterized in that the coil system of the generator (3) is mounted in the groove in such a way that the short-circuit current occurring in the coil system is minimized.

4. Power supply system according to claim 1 or 2, characterized in that a load (6a, 6b) is connected to the three-phase current system (1a, 1b) in both of the primary systems (1).

5. Power supply system according to claim 1, characterized in that the secondary three-phase current system (2) is coupled with another generator.

6. Power supply system according to claim 5, characterized in that the coupling between the primary system (1) and the secondary three-phase current system (2) is realized in such a way that energy generated by means of a generator coupled to the secondary three-phase current system (2) can be fed to the primary system (1).