WIND TURBINE SYSTEM AND INTERCONNECTION OF WIND TURBINE SYSTEMS

A wind turbine system contains a generator, a tower, and an electrical energy transmission system which is arranged in the tower and which contains a bus bar and three mutually adjacent electrical energy transmission modules. Each electrical energy transmission module has a current path that connects the bus bar to a cable termination of the electrical energy transmission module. At least two electrical energy transmission modules each contain a circuit breaker by which the current path of the electrical energy transmission module can be interrupted. The cable termination of one of the electrical energy transmission modules containing a circuit breaker is connected to the generator.

The invention relates to a wind turbine system, and to an interconnection of a plurality of wind turbine systems.

A wind turbine system, which is also described as a wind energy installation, generally comprises an electrical energy transmission system, by means of which a generator of the wind turbine system is connected to a power grid. An electrical energy transmission system of this type generally comprises a power circuit-breaker by means of which, if necessary, a current path which incorporates the generator of the wind turbine system can be rapidly interrupted. If a plurality of wind turbine systems are mutually interconnected, it can be necessary for a wind turbine system to comprise a plurality of power circuit-breakers in order to permit the interruption, for example, not only of a current path which incorporates the generator of the wind turbine system, but also of a mutually interconnected arrangement of wind turbine systems, if necessary.

The object of the invention is the disclosure of a wind turbine system having a plurality of power circuit-breakers, and of an interconnection of a plurality of such wind turbine systems.

According to the invention, this object is fulfilled by a wind turbine system having the features of claim1, and by an interconnection of such wind turbine systems having the features of claim15.

Advantageous configurations of the invention are the subject matter of the sub-claims.

A wind turbine system according to the invention comprises a generator, a tower and an electrical energy transmission system which is arranged in the tower and which comprises a busbar and three mutually adjacent electrical energy transmission modules. Each electrical energy transmission module comprises a current path which connects the busbar to a cable termination of the electrical energy transmission module. At least two electrical energy transmission modules respectively comprise a power circuit-breaker, by means of which the current path of the electrical energy transmission module can be interrupted. A cable termination of one of the electrical energy transmission modules comprising a power-circuit breaker is connected to the generator.

The invention embodies a wind turbine system, having at least two power circuit-breakers, in the form of three electrical energy transmission modules, at least two of which respectively comprise a power circuit-breaker. The current path of a first electrical energy transmission module which comprises a power circuit-breaker is connected to the generator of the wind turbine system. As a result, if necessary, a current path which is connected to the generator can be interrupted by means of the power circuit-breaker of the first electrical energy transmission module.

The other two electrical energy transmission modules can be employed, for example, for the mutual interconnection of a plurality of wind turbine systems. For example, the second electrical energy transmission module of a first wind turbine system is connected to the current path of an electrical energy transmission module of a second wind turbine system, and the current path of the third electrical energy transmission module of the first wind turbine system is connected to the current path of an electrical energy transmission module of a third wind turbine system. As the electrical energy transmission modules of the first wind turbine system are mutually connected by means of the busbar, the connection of the three wind turbine systems thus remains in place, in the event that the current path of the first electrical energy transmission module of the first wind turbine system is interrupted by means of the power circuit-breaker of the first electrical energy transmission module. As the second or third electrical energy transmission module comprises a power circuit-breaker, this power circuit-breaker can be employed to interrupt the connection of the three wind turbine systems, if necessary.

In one configuration of the invention, each electrical energy transmission module comprises a first housing part, in which a section of the busbar is routed, wherein the first housing parts of adjoining electrical energy transmission modules are mutually connected. In other words, the busbar is routed in the mutually connected first housing parts of the electrical energy transmission modules. As a result, in particular, a gas-tight encapsulation of the busbar can be achieved.

In a further configuration of the invention, each electrical energy transmission module comprises a cable terminal box which is arranged below the first housing part thereof, in which the cable termination of the electrical energy transmission module is arranged. As a result, a space-saving arrangement of cable terminal boxes below the first housing parts is achieved. This is advantageous, as the tower of a wind turbine system assumes a relatively small diameter of only a few meters, and only a limited floor area is available for the arrangement of the three electrical energy transmission modules.

In a further configuration of the invention, in the cable terminal box of that electrical energy transmission module, the cable termination of which is connected to the generator, a current transformer unit is arranged, which is designed to capture a current strength of an electric current flowing in the current path of the electrical energy transmission module and to activate the power circuit-breaker of the electrical energy transmission module for the interruption of the current path, in the event that the current strength exceeds a predefinable threshold value. The current transformer unit permits a monitoring of the current path which is connected to the generator and, if necessary, initiates an interruption of this current path by means of the power circuit-breaker.

In a further configuration of the invention, each electrical energy transmission module comprises a second housing part, which is arranged with an offset in relation to the first housing part and in relation to the cable terminal box, and in which the current path of the electrical energy transmission module is routed between the first housing part and the cable terminal box. This configuration of the invention is also intended to achieve a space-saving design of the electrical energy transmission system.

In a further configuration of the invention, the first housing part and the second housing part of each electrical energy transmission module are configured with a gas-tight design. This advantageously permits a gas-insulated design of the electrical energy transmission system.

In a further configuration of the invention, the power circuit-breaker of each electrical energy transmission module which comprises a power circuit-breaker is arranged in the second housing part of the electrical energy transmission module. In particular, this permits a gas-insulated design of power circuit-breakers.

In a further configuration of the invention, each electrical energy transmission module which comprises a power circuit-breaker comprises a combined disconnector and grounding switch, which is arranged in the first housing part thereof, by means of which the current path of the electrical energy transmission module is interruptible, and a section of the current path which is connected to the power circuit-breaker can be grounded. In particular, this permits a terminal of the respective power circuit-breaker to be grounded, prior to the reclosing of the power circuit-breaker further to the opening thereof.

In a further configuration of the invention, each electrical energy transmission module comprising a power circuit-breaker comprises a power circuit-breaker drive for the power circuit-breaker, which is arranged above the first housing part of the electrical energy transmission module. This configuration of the invention is also intended to achieve a space-saving design of the electrical energy transmission system.

In a further configuration of the invention, one of the electrical energy transmission modules comprises no power circuit-breaker. The electrical energy transmission module which comprises no power circuit-breaker can also comprise a combined disconnector and grounding switch, which is arranged in the first housing part thereof, by means of which the current path of the electrical energy transmission module is interruptible and a section of the current path can be grounded. The design of the electrical energy transmission system with one electrical energy transmission module which comprises no power circuit-breaker is more cost-effective than a design having three electrical energy transmission modules, each of which comprises a power circuit-breaker. Consequently, this design is preferred, if a third power circuit-breaker is not necessary. Otherwise, each electrical energy transmission module comprises a power circuit-breaker, by means of which the current path of the electrical energy transmission module is interruptible.

In a further configuration of the invention, the wind turbine system comprises a switch cabinet, which is arranged adjacently to the first housing part of an electrical energy transmission module. This configuration of the invention is also intended to achieve a space-saving design of the electrical energy transmission system.

In a further configuration of the invention, all control elements and display elements of the electrical energy transmission system are arranged on the same side of the electrical energy transmission system. This permits a simple operation and control of the electrical energy transmission system.

In an interconnection, according to the invention, of a plurality of wind turbine systems according to the invention, cable terminations of the electrical energy transmission modules of the wind turbine systems are connected by means of electrical connections, wherein:in each case, at least one cable termination of two mutually connected cable terminations is the cable termination of an electrical energy17transmission module which comprises a power circuit-breaker;each wind turbine system is interconnected with exactly one further wind turbine system or with exactly two further wind turbine systems;at least one wind turbine system is interconnected with exactly one further wind turbine system;at least one wind turbine system is interconnected with exactly two further wind turbine systems; andeach cable termination of an electrical energy transmission module of each wind turbine system which is interconnected with two further wind turbine systems is connected, either to the generator of the wind turbine system or to a cable termination of an electrical energy transmission module of one of the two further wind turbine systems.

An interconnection of wind turbine systems according to the invention of this type permits an interruption of the connection of two wind turbine systems by means of the power circuit-breaker of one of these two wind turbine systems, for example in the event of a defect which necessitates such an interruption. At the same time, however, it is possible to maintain the connection and operation of further wind turbine systems which, for example, are electrically arranged between the two mutually isolated wind turbine systems and an energy collector substation, to which the wind turbine systems are connected (in this regard, seeFIG.4below).

In the figures, mutually corresponding parts are identified by the same reference numbers.

FIG.1(FIG.1) shows a wind turbine system1. The wind turbine system1comprises a tower2, a nacelle3, a rotor hub4and rotor blades5. The nacelle3is arranged on the tower2. The rotor hub4is rotatably mounted on the nacelle3. The rotor blades5are arranged on the rotor hub4.

A generator6of the wind turbine system1is arranged in the nacelle3. An electrical energy transmission system7is arranged in the tower2.

The wind turbine system1, for example, is a system in an offshore wind farm.

FIG.2(FIG.2) andFIG.3(FIG.3) show an electrical energy transmission system7of a wind turbine system1according to one exemplary embodiment of the invention.FIG.2shows a perspective representation of the electrical energy transmission system7, andFIG.3shows a block diagram of the electrical energy transmission system7, incorporating a circuit diagram of the electrical energy transmission system7. In the interests of simplification, the circuit diagram is represented as a single-line diagram, in which the three-phase current path is represented by a single line.

The electrical energy transmission system7comprises a busbar8and three mutually adjacent electrical energy transmission modules9,10,11. Each electrical energy transmission module9,10,11comprises a first housing part12, a second housing part13and a cable terminal box14.

The first housing parts12of the adjacent electrical energy transmission modules9,10,11are mutually connected. In each first housing part12, a section of the busbar8is routed, i.e. the busbar8is routed in the mutually connected first housing parts12.

In the cable terminal box14of each electrical energy transmission module9,10,11, a cable termination15of the respective electrical energy transmission module9,10,11is arranged. By means of the cable termination15thereof, an electrical energy transmission module9,10,11can be electrically contact-connected, or is electrically connectable to other devices. The cable terminal box14of an electrical energy transmission module9,10,11is arranged below the first housing part12of the electrical energy transmission module9,10,11.

The second housing part13of an electrical energy transmission module9,10,11is configured with an essentially circular cylindrical design, and is arranged with an offset in relation to the first housing part12and in relation to the cable terminal box14of the electrical energy transmission module9,10,11.

The first housing parts12and the second housing parts13are configured, for example, with a gas-tight design, in order to permit the embodiment of a gas-insulated electrical energy transmission system7.

Each electrical energy transmission module9,10,11comprises a current path which connects the busbar8to the cable termination15of the electrical energy transmission module9,10,11. The current path22is routed from the busbar8in the first housing part12of the electrical energy transmission module9,10,11to the second housing part13of the electrical energy transmission module9,10,11, and via the second housing part13to the cable terminal box of the electrical energy transmission module9,10,11. The current path22to the cable termination15of the electrical energy transmission module9,10,11is routed in the cable terminal box14. The current path22of each electrical energy transmission module9,10,11thus assumes a C-shaped profile (corresponding to a capital C).

The cable termination15of a first electrical energy transmission module9is connected to the generator6. In other words, for each phase of the generator6, a power conductor is routed from the cable termination15of the first electrical energy transmission module9through the tower2to the generator6.

The cable termination15of a second electrical energy transmission module10and of the third electrical energy transmission module11are respectively connectable or connected to a power grid in which the wind turbine system1is situated. For example, the power grid is the power grid of a wind farm in which a plurality of wind turbine systems1are mutually electrically interconnected—in this regard, for example, seeFIG.4.

Each electrical energy transmission module9,10,11comprises a combined disconnector and grounding switch16which is arranged in the first housing part12thereof, by means of which the current path22of the electrical energy transmission module9,10,11is interruptible.

The first electrical energy transmission module9and the second electrical energy transmission module10respectively comprise a power circuit-breaker17which is arranged in the second housing part13of the respective electrical energy transmission module9,10. By means of the power circuit-breaker17, the current path22of the respective electrical energy transmission module9,10is interruptible.

Each of the first electrical energy transmission module9and the second electrical energy transmission module10further comprises a power circuit-breaker drive18for the power circuit-breaker17of the respective electrical energy transmission module9,10,11. The power circuit-breaker drive18is arranged in a drive housing19above the first housing part12and the second housing part13of the respective electrical energy transmission module9,10,11.

A current transformer unit20is arranged in the cable terminal box14of the first electrical energy transmission module9. The current transformer unit20is designed to capture a current strength of an electric current flowing in the current path22of the first electrical energy transmission module9and to activate the power circuit-breaker9of the first electrical energy transmission module9for the interruption of the current path22, in the event that the current strength exceeds a predefinable threshold value.

The electrical energy transmission system7further comprises a switch cabinet21, which is arranged adjacently to the first housing part12of the first electrical energy transmission module9,10,11.

All control elements and display elements of the electrical energy transmission system7are arranged on the same side of the electrical energy transmission system7.FIG.2shows exemplary contact position indicators23for the respective indication of a contact position of a power circuit-breaker17, manually operable emergency trip switches24for the respective emergency tripping of a power circuit-breaker17, contact position indicators25for the respective indication of a contact position of a disconnector and grounding switch16, gas-tightness indicators26for the respective indication of gas-tightness in the housing parts12,13of an electrical energy transmission module9,10,11, voltage indicators27for the respective indication of a voltage which is present in a current path22, and respective manually operable drives28for a disconnector and grounding switch16.

In the exemplary embodiment represented inFIGS.2and3, the third electrical energy transmission module11comprises no power circuit-breaker17, but is employed for current conduction only. According to further exemplary embodiments, however, it can be provided that the third electrical energy transmission module11also comprises a power circuit-breaker17, and is configured in the manner of the second electrical energy transmission module10.

FIG.4(FIG.4) shows an interconnection of a plurality of wind turbine systems1by means of electrical connections29of the cable terminations15of the electrical energy transmission modules9,10,11of the wind turbine systems1. An exemplary interconnection of four wind turbine systems1is represented. The wind turbine systems1are respectively represented, in an abstract manner, by a circuit diagram. Each wind turbine system1comprises a first electrical energy transmission module9, which comprises a power circuit-breaker17and the cable termination15of which is connected to the generator6of the wind turbine system1, a second electrical energy transmission module10, which also comprises a power circuit-breaker17, and a third electrical energy transmission module11, which comprises no power circuit-breaker17.

The cable termination15of the third electrical energy transmission module11of a first wind turbine system1, which is represented on the left-hand side ofFIG.4, is connected to an energy collector substation30. The cable termination15of the second electrical energy transmission module10of the first wind turbine system1is connected to the cable termination15of the third electrical energy transmission module11of a second wind turbine system1, which is represented on the right-hand side ofFIG.4, adjacently to the first wind turbine system1.

The cable termination15of the second electrical energy transmission module10of the second wind turbine system1is connected to the cable termination15of the third electrical energy transmission module11of a third wind turbine system1, which is represented on the right-hand side ofFIG.4, adjacently to the second wind turbine system1.

The cable termination15of the second electrical energy transmission module10of the third wind turbine system1is connected to the cable termination15of the third electrical energy transmission module11of a fourth wind turbine system1, which is represented on the right-hand side ofFIG.4.

An exemplary situation is further represented in which, in response to a defect, the power circuit-breaker17and the disconnector and grounding switch16of the second electrical energy transmission module10of the third wind turbine system1are tripped. As a result, the interconnection of the third wind turbine system1with the fourth wind turbine system1is interrupted. The first wind turbine system1and the second wind turbine system1can nevertheless be maintained in service. This illustrates the utility of the embodiment of wind turbine systems1having (at least) two respective power circuit-breakers17for the interconnection of a plurality of wind turbine systems1.

Although the invention has been illustrated and described in greater detail with reference to preferred exemplary embodiments, the invention is not limited by the examples disclosed, and further variations can be inferred herefrom by a person skilled in the art, without departing from the protective scope of the invention.