ELECTRONIC SWITCH

Abstract

An electronic switch has a first semiconductor switch arranged between a first source-side terminal and a first consumer-side terminal first, and a switch embodied as a thyristor and arranged between the first consumer-side terminal and a second source-side terminal. The switch is configured to generate a thermal overload from a short-circuit current produced when the switch closes. The thermal overload causes the first semiconductor switch to irreversibly transition into an open state due to a modification inside the first semiconductor switch caused by the thermal overload. This improves the switching behavior of the electronic switch in the event of a fault. Furthermore, an electrical network with at least one electronic switch connected to an energy source and a method for operating such an electronic switch or such an electrical network is also described.

Claims

1.-11. (canceled)

12. An electronic switch, comprising a first consumer-side terminal, a first source-side terminal and a second source-side terminal, a first semiconductor switch arranged between the first source-side terminal and the first consumer-side terminal, and a switch embodied as a thyristor and arranged between the first consumer-side terminal and the second source-side terminal, with the switch being configured to generate a thermal overload from a short-circuit current produced when the switch closes, wherein the thermal overload causes the first semiconductor switch to irreversibly transition into an open state due to a modification inside the first semiconductor switch caused by the thermal overload.

13. The electronic switch of claim 12, wherein the first semiconductor switch has a modular construction and comprises bonding wires, with the irreversible transition into the open state taking place by melting the bonding wires.

14. The electronic switch of claim 12, further comprising: a second semiconductor switch and a second consumer-side terminal, wherein the second semiconductor switch is arranged between the second source-side terminal and the second consumer-side terminal.

15. The electronic switch of claim 14, wherein the switch is arranged between the first consumer-side terminal and the second consumer-side terminal.

16. The electronic switch of claim 12, wherein the first semiconductor switch comprises bonding wires.

17. The electronic switch of claim 14, wherein the second semiconductor switch comprises bonding wires.

18. An electrical network, comprising: an energy source, and at least one electronic switch having a first source-side terminal and a second source-side terminal connected to the energy source, and a first consumer-side terminal, the at least one semiconductor switch being arranged between the first source-side terminal and the first consumer-side terminal, and a switch embodied as a thyristor and arranged between the first consumer-side terminal and the second source-side terminal, with the switch being configured to generate a thermal overload from a short-circuit current produced when the switch closes, wherein the thermal overload causes the at least one semiconductor switch to irreversibly transition into an open state due a modification inside the at least one semiconductor switch caused by the thermal overload.

19. The electrical network of claim 18, wherein the electrical network is embodied as a DC voltage network or AC voltage network, in particular as a three-phase network.

20. The electrical network of claim 18, comprising at least one electrical consumer.

21. A method for operating at least one electronic switch or an electrical network comprising the at least one electronic switch, the method comprising: connecting the at least one semiconductor switch between a first source-side terminal connected to an energy source and a first consumer-side terminal; connecting a switch embodied as a thyristor between the first consumer-side terminal and a second source-side terminal connected to the energy source; and generating with the switch a thermal overload from a short-circuit current produced when the switch closes, with the thermal overload simultaneously causing the first semiconductor switch to irreversibly transition into an open state due to a modification of the first semiconductor switch.

Description

[0026] The invention is described and explained in more detail below on the basis of the exemplary embodiments shown in the figures. In the drawings:

[0027] FIG. 1 to FIG. 3 show exemplary embodiments of an electronic switch,

[0028] FIG. 4 and FIG. 5 show exemplary embodiments of an electrical network, and

[0029] FIG. 6 shows the temporal course of control signals.

[0030] FIG. 1 shows a first exemplary embodiment of an electronic switch 1. This has a first source-side terminal 31, a second source-side terminal 32 and a first consumer-side terminal 33. A semiconductor switch 3 is arranged between the first source-side terminal 31 and the first consumer-side terminal 33. In this exemplary embodiment, said semiconductor switch comprises two individual semiconductors, which are each able to switch current in one direction, so that the semiconductor switch is able to guide and switch currents in both directions. A control circuit 21 is used to control the two semiconductors. In order to ensure a safe turning off of the electronic switch 1, even in the event of a failure to turn off the semiconductor switch 3, a switch 4 is arranged between the first consumer-side terminal 33 and the second source-side terminal 32. In the event of a failure to turn off the semiconductor switch 3, the switch 4 is closed, Between the first and the second source-side terminal, a short-circuit current driven by an energy source 7 (not shown here) is formed, which overloads the semiconductor switch 3 in such a way that it transitions into the blocking, i.e. non-conducting state. A safe separation between the first source-side terminal 31 and the first consumer-side terminal 33 is established as a result. In other words, the first source-side terminal 31 and the first consumer-side terminal 33 are electrically isolated from one another. This electronic switch 1 involves a single-pole switch.

[0031] FIG. 2 shows an exemplary embodiment of an electronic switch 1 in the form of a two-pole switch, For the avoidance of repetition, reference is made to the description relating to FIG. 1 and the reference characters therein. This electronic switch 1 has a second consumer-side terminal 34 in addition to the previously mentioned terminals. A further semiconductor switch 5 is now arranged between the switch 4 and the second source-side terminal 32. The switch 4 is located between the first consumer-side terminal 33 and the second consumer-side terminal 34, The further semiconductor switch 5 is located between the second source-side terminal 32 and the second consumer-side terminal 34. In this context, the semiconductor switch 3 and the further semiconductor switch 5 are able to use the same control circuit 21 or, as shown in this figure, can be connected to different control circuits 21. In the event of a failure to turn off the semiconductor switch 3 and further semiconductor switch 5, closing the switch 4 brings about a short-circuit current, which is driven by an energy source 7 (not shown here) and transitions at least one of the semiconductor switches 3, 5 or both semiconductor switches 3, 5 into the nonconducting state, thus opening the electronic switch 1.

[0032] The exemplary embodiment of the two-pole electronic switch 1 in accordance with FIG. 2 is especially suitable for use in a DC voltage network, where the energy is transferred by means of two potentials, between which a DC voltage is applied. Likewise, the single-pole electronic switch in accordance with FIG. 1 is especially suitable for use in a DC voltage network when it is sufficient to establish the voltage-free state. This is the case, for example, if the subnetworks interconnected via the electronic switch are grounded.

[0033] FIG. 3 shows an electronic switch for a three-phase network as an example of an AC voltage network. For the avoidance of repetition, reference is made to the description relating to FIGS. 1 and 2 and the reference characters therein. For connecting on the source and consumer side, this electronic switch 1 has a further source-side terminal 36 and a further consumer-side terminal 37. In this context, in this arrangement three switches 4 are present and are arranged between the consumer-side terminals 33, 34, 37. This may take place in a delta connection, for example, as shown. Alternatively, it is also possible to arrange the three switches 4 of a three-phase network in a star connection. As soon as the semiconductor switches 3, 5 open, the switches 4 can be closed. This can take place at the same time, or with a time delay. Provided at least two of the three semiconductor switches 3, 5 open, the energy transfer between the source-side terminals 31, 32, 36 and the consumer-side terminals 33, 34, 37 is interrupted. If there is a failure to turn off in the case of two or even all three semiconductor switches 3, 5, a short-circuit current is generated via at least one of the switches 4, which leads to the remaining semiconductor switches 3, 5 transitioning into the opened state, in the worst case except for one of the semiconductor switches 3, 5. This means that energy transfer is safely interrupted by the electronic switch 1.

[0034] FIG. 4 shows an exemplary embodiment of an electrical network 2. This can involve a DC voltage network or an AC voltage network. The electronic switch 1 is arranged between an energy source 7 and an electrical consumer 6, in order to protect the electrical consumer 6. A single-pole electronic switch 1 is involved in this context. However, a two-pole electronic switch 1 can also be used, as shown in FIG. 2. Likewise, it is also possible for a plurality of electrical consumers 6 or an electrical subnetwork to be arranged at the consumer-side terminals 33, 34 of the electronic switch 1.

[0035] FIG. 5 shows one such exemplary embodiment of an electrical network 2 with a plurality of electronic switches 1. These electronic switches 1 can be designed in a single-pole or two-pole manner in each case. A first electronic switch 1 on the left-hand side of the diagram is used to disconnect the energy source 7 from the electrical subnetwork 21. In turn, a large number of electrical consumers 6 are connected to the electrical subnetwork 21. In this context, each of these electrical consumers 6 can be disconnected from the electrical subnetwork 21 and thus from the energy source 7 via an electronic switch 1. Alternatively, it is also possible to provide an electronic switch 1 as a protective device for a group of electrical consumers 6, i.e. for at least two electrical consumers 6.

[0036] FIG. 6 shows the temporal course of a control signal 61 for the semiconductor switch 3 and a control signal 62 for the switch 4. A time delay t* is introduced after switching off the semiconductor switch 3, after the expiration of which the switch 4 is switched on. During the duration of the time delay t*, for example, it is possible to reliably identify a failure to turn off the semiconductor switch, which makes it necessary to switch on the switch 4. Should the switch 4 be switched on independently of the identification of a failure to turn off, the time delay t* can also be chosen to be zero.

[0037] In summary, the invention relates to an electronic switch, wherein the electronic switch has a semiconductor switch, a first consumer-side terminal, a first source-side terminal and a second source-side terminal, wherein the semiconductor switch is arranged between the first source-side terminal and the first consumer-side terminal. In order to improve the electronic switch with regard to its turn-off behavior in the event of a fault, it is proposed that the semiconductor switch is embodied such that, in the event of an overload due to exceeding a permissible current value, it transitions into the opened state, wherein a switch is arranged between the first consumer-side terminal and the second source-side terminal. In other words, in summary, the invention relates to an electronic switch, wherein the electronic switch has a semiconductor switch, a first consumer-side terminal, a first source-side terminal and a second source-side terminal, wherein the semiconductor switch is arranged between the first source-side terminal and the first consumer-side terminal. In order to improve the electronic switch with regard to its turn-off behavior in the event of a fault, it is proposed that a switch is arranged between the first consumer-side terminal and the second source-side terminal, wherein the semiconductor switch is embodied such that it irreversibly transitions into the opened state due to the effect of a thermal overload inside the semiconductor switch, wherein the switch is configured to generate the thermal overload by way of closing the switch and the short-circuit current that forms as a result. This invention further relates to an electrical network with an energy source and at least one electronic switch of this kind, wherein the first source-side terminal and the second source-side terminal of the electronic switch are connected to the energy source. Furthermore, the invention relates to a method for operating an electronic switch of this kind or an electrical network of this kind, wherein the switch is closed when the semiconductor switch and/or the further semiconductor switch is turned off.