DC voltage line circuit breaker

#The present invention relates to a DC voltage line circuit breaker, a method for operating a DC voltage line circuit breaker, and a DC line system.

#Electrical energy is generally generated in power stations as three-phase alternating current. For transmission, this energy is transformed by power transformers to very high electrical AC voltages and transmitted over overhead lines. In the case of very long overhead lines, however transmission of energy with direct current is associated with lower losses and is therefore more favorable.

#In the case of DC transmission, however, there are difficulties in the prior art in controlling power flows in meshed line systems. Therefore, for DC transmission, almost exclusively point-to-point connections without any branches or meshes have been used until now. However, for the future, construction and expansion of DC line systems is planned. For this, DC voltage line circuit breakers are needed in order to increase the availability of the planned DC line systems. DC voltage line circuit breakers are used for selectively disconnecting parts of a line system in the event of a fault and thus preventing failure of the entire line system.

#The above-described properties, features and advantages of this invention and the way in which these are achieved will be made clearer and more easily understandable in connection with the following description of the exemplary embodiments, which will be explained in more detail in connection with the drawings, in which:

#FIG. 1 shows a circuit arrangement of a DC voltage line circuit breaker;

#FIG. 2 shows a graph illustrating the source current profile of the circuit arrangement in comparison with a known circuit arrangement;

#FIG. 1 shows a circuit arrangement of a DC voltage line circuit breaker 100. The DC voltage line circuit breaker can be integrated in a DC line system in order to disconnect selectively part of the DC line system in the event of a short circuit. The DC voltage line circuit breaker 100 can be intended, for example, for use in a high-voltage DC line system. The DC voltage line circuit breaker 100 in a DC line system enables protection of the positive phase with respect to the ground potential, the negative phase with respect to the ground potential, and the positive phase with respect to the negative phase.

#The DC voltage line circuit breaker 100 has a first to a seventh node 101 . . . 107. The nodes 101 . . . 107 are circuit nodes of the DC voltage line circuit breaker 100 which are each at an electrical potential. The nodes 101 . . . 107 can accordingly each also comprise electrical conductor sections if the electrical resistances of these conductor sections are negligible.

#A DC voltage 200 can be applied between the first node 101 and the second node 102 of the DC voltage line circuit breaker 100. The DC voltage 200 can be a source voltage, which is applied to a DC line system by a high-voltage rectifier. The first node 101 and the second node 102 in this case form an input side of the DC voltage line circuit breaker 100 and of the DC line system connected to the DC voltage line circuit breaker 100. The DC voltage 200 applied between the first node 101 and the second node 102 can be 500 kV, for example. The DC voltage 200 can also assume higher voltage values of more than 1200 kV, however. In the DC line system in which the DC voltage line circuit breaker 100 is used, the DC voltage 200 can excite a direct current of 20 kA or more.