Hybrid protection switching device, hybrid contactor and method

Abstract

The invention relates to a hybrid protection switching device (30), in particular a DC hybrid protection switching device, comprising at least one mechanical interruption switch (10) and at least one semiconductor protection switch (12), in particular a semiconductor relay, which is electrically connected in parallel to the mechanical interruption switch (10). It is proposed that the mechanical interruption switch (10) has, in particular, a magneto-sensitive tripping element (14), which is at least partially composed of a magnetic shape memory alloy (16).

Description

Technical Field

[0001] The invention relates to a hybrid protective switch device according to the preamble of claim 1 , a hybrid contactor according to claim 15 and a method according to claim 16 . Background Art

[0002] In particular, from the article “New Switching Technology for DC Grids” by the author Wolfgang Hauer at the 30th International Conference on Electrical Contacts, a hybrid protection switch device is known, which has at least one mechanical disconnector and at least one switching semiconductor circuit breaker electrically connected in parallel with the mechanical disconnector. Summary of the invention

[0003] In particular, the object of the invention is to provide a universal device with advantageous properties in terms of overcurrent protection. This object is achieved according to the invention by the features of the invention, while advantageous embodiments and improvements of the invention can be found in the dependent claims.

[0004] The invention relates to a hybrid protection switch device, in particular a DC hybrid protection switch device, which comprises at least one mechanical interrupter switch and at least one semiconductor protection switch, in particular a semiconductor relay, which is electrically connected in parallel with the mechanical interrupter switch.

[0005] It is proposed that the mechanical interrupter has, in particular, a magnetically sensitive tripping element which at least partially consists of a magnetic shape memory alloy (also referred to as MSM material = Magnetic Shape Memory). As a result, the overcurrent protection can be advantageously increased, in particular by making it possible to achieve a particularly high response speed / tripping speed of the mechanical interrupter. Advantageously, a fast-reacting and therefore safe and cost-effective overcurrent protection can be achieved, which is particularly suitable for DC networks in which, in the event of a fault, in particular compared to AC networks, very high rates of current increase (in the range of up to 100 A / μs) and very high currents (in the range of up to 10 kA) can occur. Advantageously, high speeds can be achieved in rated operation with low electrical losses, as can occur, for example, in contactors based purely on semiconductor relays.

[0006] "Hybrid protection switch device" should be understood in particular as a component, especially a design and / or functional component, of a hybrid contactor that is especially reliable in function. "Hybrid contactor" should be understood in particular as a hybrid power switch that is configured to achieve an emergency disconnection of the current in the circuit by the interaction of mechanical and semiconductor-based switch components. In particular, the hybrid protection switch device is configured to be used in a hybrid contactor and / or to be installed in a hybrid contactor. Advantageously, the hybrid contactor is configured to protect the circuit, the equipment connected thereto and / or its lines from overload and / or overcurrent and / or short-circuit current. "Setting" should be understood in particular as special programming, design and / or equipment. An object is configured for a specific function and should be understood in particular as the object performing and / or executing the specific function in at least one application and / or operating state. Here, the DC hybrid protection switch device is configured to interrupt the DC circuit. In particular, the mechanical interrupter is configured to generate the interruption of the circuit at least by the mechanical movement of the component, preferably by the mechanical disconnection of the electrical contacts of the circuit. In particular, the semiconductor protection switch is configured to generate the interruption of the circuit at least by electrically controlling the semiconductor component. For example, the semiconductor protection switch can be configured as an insulated gate electrode (English: Insulated-Gate Bipolar Transistor (IGBT)) or as a metal oxide semiconductor field effect transistor (English: Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET). In particular, the semiconductor protection switch constitutes a semiconductor interrupter switch, and vice versa.

[0007] In particular, the tripping conditions for circuit disconnection by the hybrid protective switch device include overcurrent conditions, in particular short circuit conditions and / or overload conditions. In particular, the tripping conditions, in particular in short circuit conditions, may include magnetic tripping conditions. In addition, the tripping conditions, in particular in overload conditions, may include thermal tripping conditions. In this case, the tripping element is not only provided for thermally induced deformation, in particular in overload conditions, but also for magnetically induced deformation, in particular in short circuit conditions. Particularly preferably, the deformation at least includes a change in the length of the tripping element, in particular a change in the length along the longitudinal axis of the tripping element. Advantageously, the tripping element is provided to generate a movement and / or force for disconnecting the circuit, in particular a movement and / or force for disconnecting the circuit directly due to the deformation. Advantageously, the movement for disconnecting the circuit is a change in the stroke and / or longitudinal extension of the tripping element. It is also conceivable that the tripping element is provided to generate a movement and / or force for disconnecting the circuit due to a deformation in a direction that is angled and / or perpendicular to the longitudinal axis of the tripping element. The longitudinal direction is particularly at least substantially parallel to the main extension direction of the trip element, wherein, here, the "main extension direction" of the object should be particularly understood as such a direction, which extends parallel to the longest side of the smallest geometric cuboid that just completely surrounds the object. In particular, the trip element is arranged as an actuating switch, such as a toggle switch, which disconnects the electrical contacts of the circuit in the off state. In particular, the current in the case of tripping is greater than the rated current, in particular the (direct current) rated current for household or industrial use. Here, the trip unit can be designed for any rated current, for example for (direct current) rated currents of 63A, 100A, 200A, etc., but can also be used for rated currents that are particularly significantly larger or significantly smaller. In particular, the current in the case of overload is greater than the rated current, preferably for at least a period of time in the range of seconds or minutes. For example, in the case of an AC circuit, an overload situation occurs at a current in the range of at least 1.15 times, preferably 1.45 times, higher than the rated current. It is assumed that similar limit values ​​in DC circuits are also applicable as in AC circuits. Furthermore, the current in the case of a short circuit is in particular greater than the current in the case of an overload. In particular, in an AC circuit, a short circuit occurs at a current in the range of at least 5 times, preferably 10 times, the rated current. In the case of a short circuit, similar limit values ​​are assumed to apply in a DC circuit as in an AC circuit.

[0008] In particular, the tripping element is configured to be separated from the printed conductor of the circuit to be monitored. Preferably, the tripping element is at least partially, preferably completely arranged in the near region of the current-guided conductor section of the circuit to be monitored. In this context, "near region" should be understood in particular as such a region, which is formed by points, which are arranged away from the current-guided conductor section at most ten times, preferably at most seven times, preferably at most five times and particularly preferably at most three times the wire diameter of the current-guided conductor section. In particular, the points forming the near region each have a distance of at most 10mm, preferably at most 5mm and particularly preferably at most 3mm from the conductor section. In particular, the tripping element is arranged relative to the current-guided conductor section of the circuit to be monitored so that the magnetic field generated at least temporarily by the strong current increase is extended / guided by the tripping element. Preferably, the tripping element and the current-guided conductor section of the circuit to be monitored extend at least substantially parallel to each other at least in the near region. “Substantially parallel” is to be understood here in particular as an orientation of a direction relative to a reference direction, in particular in a plane, wherein the direction has a deviation relative to the reference direction of in particular less than 8°, advantageously less than 5° and particularly advantageously less than 2°. Preferably, the current-conducting conductor section of the circuit to be monitored is designed as a part other than an electrical coil, in particular runs straight or curved, preferably is not wound and is not wound multiple times.

[0009] In particular, the current-conducting conductor section of the circuit to be monitored is configured as a single conductor. In particular, the tripping element is configured to react to a (strong) magnetic field change generated by the current-conducting conductor section of the circuit to be monitored, in particular by a length change. It is also conceivable that the conductor section generates heat in the circuit to be monitored in the case of a trip, in particular due to a current exceeding the rated current, wherein the thermal radiation generated thereby can be absorbed by the tripping element and thereby can cause another optional thermal tripping situation. Particularly preferably, the current flowing in the conductor section in the circuit to be monitored in the case of a trip, in particular in the case of a short circuit, generates a tripping magnetic field for the tripping element. In particular, the tripping element is influenceable and / or deformable by means of the conductor section and / or by means of a magnetic field generated by the conductor section, in particular in the case of a trip. The tripping element can be configured as a plunger, an elongated shape, a rod shape, a pin shape and / or a cylindrical shape. In particular, the main deformation axis is the axis of maximum deformation of the tripping element. Preferably, the main deformation direction is arranged at least substantially parallel to the longitudinal axis of the tripping element. Preferably, the tripping element has an at least substantially constant cross section. Preferably, the tripping element is designed in one piece.

[0010] Advantageously, the tripping element is formed as a solid body. However, it is also conceivable that the tripping element is formed, in particular at least in sections, as a hollow body, such as a hollow cylinder, and / or a solid body with grooves and / or cavities, etc. Preferably, the tripping element is at least mostly, especially completely, formed of a magnetic shape memory alloy. Particularly preferably, the hybrid switching device has a single tripping element. However, it is also conceivable that the hybrid switching device has a plurality of tripping elements that are in particular identical or different in structure to each other. In this way, an object having an "at least substantially constant cross-section" should be understood in particular that for any first cross-section of the object along at least one direction and any second cross-section of the object along the direction, the minimum area of ​​the difference surface formed when the cross-section is superimposed is a maximum of 20%, advantageously a maximum of 10% and particularly advantageously a maximum of 5% of the area of ​​the larger cross-section of the two cross-sections. Here, the expression "at least mostly" should be understood in particular as at least 55%, advantageously at least 65%, preferably at least 75%, particularly preferably at least 85% and particularly advantageously at least 95%, but in particular completely.

[0011] Preferably, the magnetic shape memory alloy contains nickel, manganese and gallium. Particularly preferably, the magnetic shape memory alloy is a nickel-manganese-gallium alloy. Alternatively, the magnetic shape memory alloy may also be an iron-palladium alloy and / or an iron-palladium alloy. In addition, the magnetic shape memory alloy may also be configured as a foam and / or a composite structure and / or a particle and / or a porous material, wherein, in particular in the case of a composite material, it is conceivable that the nickel, manganese and / or gallium components may be embedded in the matrix. In addition, the magnetic shape memory alloy may be configured as a single crystal. Preferably, the trip element is configured as a single crystal composed of a magnetic shape memory alloy. It is also conceivable that the trip element consists of a plurality of, in particular a few, for example two or three or four or five individual single crystals. However, it is also conceivable that the magnetic shape memory alloy is configured as a polycrystalline.

[0012] In particular, the mechanical interrupter is configured to commutate the current already at the beginning of the disconnection process of the mechanical interrupter to the semiconductor protection switch in the event of an overcurrent. In particular, here, the voltage of the arc ignited when the mechanical interrupter is opened can optionally be used for commutation. By commutating the current, the arc is then extinguished in particular. Preferably, the tripping condition is non-destructive and reproducible after resetting all components of the hybrid protection switch device. Advantageously, contact burnout can be avoided.

[0013] In addition, it is proposed that the mechanical interrupter has a disconnection time of less than 400 μs, preferably less than 200 μs in the case of tripping. As a result, a particularly fast reaction can be achieved. Advantageously, applicability to a DC grid can be achieved. Advantageously, a particularly high safety can be achieved. Advantageously, by accelerating the mechanical disconnection of the hybrid contactor, the use of smaller semiconductor protection switches and / or varistors in other branches of the hybrid contactor can be achieved, especially because a relatively small current through the hybrid contactor must be extinguished overall. In this case, the "disconnection time" of the mechanical interrupter should be understood in particular as the time elapsed between the occurrence of a fault current, such as a short-circuit fault current, and the partial disconnection of the mechanical interrupter, wherein the arc generated during the disconnection provides sufficient voltage for the electronic components of the semiconductor interrupter, especially for commutating the current to the branch of the hybrid protection switch device with the semiconductor interrupter. In particular, the disconnection time can be understood as the time from the occurrence of the fault current (start of the disconnection movement of the trip element) to the time when the maximum current value is reached in the branch of the hybrid protection switch device with the mechanical protection switch (partial disconnection, wherein the arc voltage generated corresponds to the activation voltage of the semiconductor protection switch). In particular, the disconnection time can also be understood as the time from the occurrence of a fault current to the start of the current flow through the branch of the hybrid protective switch device with the semiconductor protective switch. In particular, at least substantially the same voltage is applied to the components of the circuit that are electrically connected in parallel. Therefore, when the voltage in the branch of the hybrid protective switch device with the mechanical protective switch increases, the voltage at the semiconductor protective switch also increases at the same time, so that "free switching" of the semiconductor protective switch occurs starting from a certain voltage.

[0014] In addition, it is proposed that the trip element, in particular the trip element produced by the (mechanical) surface treatment of the magnetic shape memory alloy, comprises a plurality of twin boundaries that can be coherently moved. Therefore, a high contraction or expansion speed of the trip element can be advantageously achieved. Advantageously, a particularly high safety can be achieved. In particular, each twin boundary of the magnetic shape memory alloy has a maximum movement speed, which is additionally dependent on the specific microstructure of the material and / or the configuration of the twin boundary. Through a plurality of twin boundaries, the maximum achievable movement speed can therefore be advantageously increased, and if necessary, even to the extent that the limitation of the movement speed is dominated by the inevitable mass inertia of the volume to be moved of the trip element. In particular, additional twin boundaries can be produced by performing appropriate surface treatment on the magnetic shape memory alloy, for example, roughening the surface of the magnetic shape memory alloy, shot peening the surface of the magnetic shape memory alloy, etc.

[0015] Here, a particularly high / optimal movement speed for deformation of the trip element can advantageously be achieved when the distance between adjacent twin boundaries of the trip element is less than 300 μm, preferably less than 150 μm and preferably less than 100 μm. In particular, here, the distance between adjacent twin boundaries is measured in the longitudinal direction of the trip element.

[0016] Furthermore, it is proposed that the mechanical interrupter is designed without a coil. This advantageously reduces the complexity of the hybrid protective switch device, in particular the hybrid contactor, preferably the mechanical interrupter. Advantageously, a simple and / or cost-effective design can be achieved. Advantageously, a particularly compact design of the hybrid protective switch device, in particular the hybrid contactor, can be achieved.

[0017] Furthermore, the complexity can be further reduced, and thus the costs can be particularly advantageously reduced, if the hybrid protective switch has a design without, in particular completely without, for example, a choke connected upstream of a mechanical interrupter. Preferably, the entire hybrid contactor is free of any inductors / coils. Advantageously, due to the high speed of the mechanical interrupter, a choke for additionally delaying the current increase in the event of a fault is superfluous. Advantageously, a particularly compact design of the hybrid protective switch, in particular of the hybrid contactor, can be achieved. Another advantage of the design without a coil, in particular also without a choke, is that, in addition to reducing costs and reducing the installation space, the power loss in rated operation is also reduced (also in the DC circuit).

[0018] Furthermore, it is proposed that the mechanical interrupter switch is designed to have at least substantially no magnetic flux conducting components other than the magnetic shape memory alloy of the tripping element. As a result, the inductive resistance can be advantageously minimized, especially in the case of a short circuit, so that time constants and / or heat losses can be advantageously reduced, so that a particularly high reaction speed can be achieved. In particular, the magnetic field generated by the overcurrent in the event of a fault, especially in the case of direct current, is already high enough to reliably switch the tripping element. In particular, the tripping element is designed to have no further magnetic flux conducting components other than the magnetic shape memory alloy.

[0019] Furthermore, it is proposed that the hybrid protective switch device has at least one further mechanical interrupter switch which is arranged in series with the semiconductor protective switch and which is arranged to trip in a time-shifted and / or slower manner relative to the mechanical interrupter switch. This advantageously enables a particularly high level of safety. In particular, the further mechanical interrupter switch is arranged to provide galvanic isolation of the circuit (which cannot be achieved only by semiconductor protective switches and / or varistors). In particular, the dynamic requirements on the further mechanical interrupter switch are much lower than on the mechanical interrupter switch. In particular, the further mechanical interrupter switch is also arranged in series with the mechanical interrupter switch. In particular, the further mechanical interrupter switch forms the isolating switch of the hybrid protective switch device.

[0020] Particularly advantageous switching of the further mechanical interrupter switch can be achieved if the further mechanical interrupter switch has a tripping element which is at least partially composed of a magnetic shape memory alloy. Advantageously, a simple design can be achieved.

[0021] Furthermore, a particularly high compactness and / or cost-effectiveness of the hybrid protection switchgear can advantageously be achieved when the tripping element of a mechanical interrupter switch also simultaneously represents the tripping element of another mechanical interrupter switch. Furthermore, a compact design can advantageously be achieved.

[0022] Furthermore, it is proposed that the hybrid protective switch device has a delay unit, which is arranged to delay the action of the tripping element on the other mechanical interrupter in time relative to the action of the tripping element on the mechanical interrupter. The delay unit can be designed, for example, as a simple spacing between the other mechanical interrupter and the tripping element or with another component of the hybrid protective switch device that is actuated by the tripping element (e.g. a disconnected conductor segment). In this way, the actuation of the other mechanical interrupter only occurs when the tripping element has expanded slightly and / or when the other component of the hybrid protective switch device that is actuated by the tripping element has moved slightly.

[0023] In addition, it is proposed that the magnetic shape memory alloy is configured as a magnetic high-temperature shape memory alloy. As a result, reliable operation of the hybrid protection switch device in a large operating temperature range can be advantageously achieved. Advantageously, high safety can be achieved. Preferably, the magnetic shape memory alloy has at least one, in particular exactly one, first transformation temperature, in particular a first transformation temperature from at least one martensite phase to at least one austenite phase. Particularly preferably, the magnetic shape memory alloy has at least one, in particular exactly one, second transformation temperature, in particular a second transformation temperature from at least one ferromagnetic phase to at least one paramagnetic phase. Advantageously, the first transformation temperature and the second transformation temperature are selected so that they are at least higher than the temperature of the trip element in a normal operating state, in particular when there is no tripping. Preferably, the magnetic high-temperature shape memory alloy is characterized in that the first transformation temperature and / or the second transformation temperature is at least 60°C, advantageously at least 70°C, particularly advantageously at least 80°C and preferably at least 100°C. As a result, false tripping, for example due to an increase in ambient temperature, can be advantageously prevented.

[0024] In addition, it is proposed that the mechanical interrupter switch includes a thermal-sensitive tripping element in addition to the magnetic-sensitive tripping element. Thus, additional overload protection can be advantageously achieved. Advantageously, particularly high safety can be achieved. In particular, the thermal-sensitive tripping element is composed of a thermal shape memory alloy, such as Nitinol. It is conceivable that the thermal shape memory alloy and the magnetic shape memory alloy connected to each other constitute a common tripping element or are constituted as two separate tripping elements, for example in the form of two adjacent or interconnected strips. In addition, it is also conceivable that the tripping element is composed of a material having a magnetic shape memory effect, in particular a magnetic high-temperature shape memory effect and a thermal shape memory effect. Preferably, the tripping element is constituted as a thermal and magnetic shape variable. "Thermal and / or magnetic shape variable material" should be understood in particular as such a material, which is affected by means of temperature increase, in particular heat energy supply and / or by means of a magnetic field, in particular an external magnetic field, and is advantageously arranged in at least one operating state to at least depend on the temperature of the material and / or at least depend on the magnetic field to change at least one material property and / or shape. However, it is also conceivable that the hybrid circuit breaker device is designed without a thermal tripping element.

[0025] In addition, a hybrid contactor, in particular a DC hybrid contactor, is proposed, which has a hybrid protection switch device and at least one varistor electrically connected in parallel with the hybrid protection switch device. As a result, advantageous characteristics in terms of speed and / or safety can be achieved. Advantageously, the hybrid contactor is much faster than a mechanical power switch with a current interruption time in the millisecond range, for example, and is much more advantageous in terms of manufacturing and / or maintenance than a pure semiconductor power switch. "Direct current" should be understood in particular as direct current. In particular, the varistor is electrically connected in parallel with the mechanical interrupter. In particular, the varistor is electrically connected in parallel with the semiconductor protection switch. In particular, the varistor is arranged to guide the current to zero through the semiconductor protection switch ("slow") after extinguishing.

[0026] Furthermore, it is proposed that the hybrid contactor has an electromagnet and / or a capacitor which is electrically connected in parallel with the mechanical interrupter switch and can be discharged by means of the switch, the electromagnet and the capacitor each being at least configured to allow a controlled disconnection of the circuit monitored by the hybrid protective switch device. As a result, a controlled disconnection of the hybrid contactor can advantageously be achieved, in particular under load, preferably without contact burnout. In particular, the electromagnet, preferably the magnetic field generated by the electromagnet, is configured to trigger a tripping element of the mechanical interrupter switch in a controlled manner, preferably to deform the tripping element. In particular, the capacitor is configured to generate a high discharge current when the switch is closed, by means of which a short-circuit situation can be simulated, so that the tripping element is triggered and the circuit is disconnected.

[0027] Furthermore, a method for operating a hybrid protective switch device, in particular a DC hybrid protective switch device, is proposed, which has at least one mechanical interrupter and at least one semiconductor protective switch, in particular a semiconductor relay, which is electrically connected in parallel with the mechanical interrupter, wherein the mechanical interrupter is actuated by a shape change of a magnetic shape memory alloy in the event of an overcurrent. As a result, the protection against overcurrents can be advantageously increased, in particular by achieving a particularly high response speed and tripping speed of the mechanical interrupter. Advantageously, a more responsive and therefore safer and more cost-effective overcurrent protection can be achieved.

[0028] In this context, the hybrid protection switch device according to the invention, the hybrid contactor according to the invention and the method according to the invention should not be limited to the applications and embodiments described above. In particular, the hybrid protection switch device according to the invention, the hybrid contactor according to the invention and the method according to the invention can have a number different from the number of individual elements, method steps, components and units mentioned herein to perform the functional mode described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Further advantages result from the following description of the drawings. Three embodiments of the invention are shown in the drawings. The drawings, the description and the claims contain many combined features. It is also appropriate for a person skilled in the art to consider these features individually and to combine them into meaningful further combinations. In the drawings:

[0030] Figure 1 A schematic circuit diagram of a hybrid contactor with a hybrid protective switch device is shown;

[0031] Figure 2a A schematic diagram showing a portion of a hybrid protective switchgear in a closed state;

[0032] Figure 2b A schematic diagram showing a portion of a hybrid protective switchgear in an open state;

[0033] Figure 3a Schematically showing a top view of a mechanical disconnector of a hybrid protective switch device,

[0034] Figure 3b Schematically showing a top view of a slightly modified mechanical disconnector switch of a hybrid protective switchgear;

[0035] Figure 4 A magnetically sensitive tripping element of a mechanical interrupter switch having a schematic internal structure is schematically shown;

[0036] Figure 5 A schematic flow chart of a method for operating a hybrid protective switchgear is shown;

[0037] Figure 6 Schematically showing the time-dependent current curves through the components of the hybrid contactor;

[0038] Figure 7 A schematic circuit diagram of a hybrid contactor with a hybrid protective switchgear and an additional electromagnet is shown; and

[0039] Figure 8 A schematic circuit diagram of a hybrid contactor with a hybrid protective switching device and an additional capacitor is shown. DETAILED DESCRIPTION

[0040] Figure 1A schematic circuit diagram of a hybrid contactor 28 is shown. The hybrid contactor 28 is designed as a DC hybrid contactor. The hybrid contactor 28 is provided for automatically interrupting the circuit and the current in the event of a fault with a fast response. The hybrid contactor 28 comprises a hybrid protective switch device 30. The hybrid protective switch device 30 is designed as a DC hybrid protective switch device. The hybrid protective switch device 30 comprises a mechanical disconnector 10. The mechanical disconnector 10 has a disconnection time 36 of less than 400 μs, preferably even less than 200 μs, in the event of a trip (see Figure 4 ). The mechanical interrupter switch 10 is arranged to disconnect the electrical contacts particularly quickly and / or automatically in the event of a fault. When the mechanical interrupter switch 10 is disconnected, a short arc is generated. When the mechanical interrupter switch 10 is disconnected, the voltage dropped at the mechanical interrupter switch 10 increases. The hybrid protective switch device 30 comprises a semiconductor protective switch 12. The semiconductor protective switch 12 is designed as a semiconductor relay (for example a MOSFET or an IGBT). The semiconductor protective switch 12 is electrically connected in parallel with the mechanical interrupter switch 10. Since the semiconductor protective switch 12 is electrically connected in parallel with the mechanical interrupter switch 10, the voltage dropped at the semiconductor protective switch 12 always corresponds to the voltage dropped at the mechanical interrupter switch 10. The semiconductor protective switch 12 is arranged to take over the current from the disconnected mechanical interrupter switch 10 from a determined minimum arc voltage.

[0041] The hybrid contactor 28 includes a varistor 32. The varistor 32 is electrically connected in parallel with the hybrid protection switch device 30. The varistor 32 is electrically connected in parallel with the mechanical interrupter 10. The varistor 32 is electrically connected in parallel with the semiconductor protection switch 12. Since the semiconductor protection switch 12 is electrically connected in parallel with the mechanical interrupter 10, the voltage dropped at the varistor 32 always corresponds to the voltage dropped at the mechanical interrupter 10. The varistor 32 is configured to guide the current taken over from the semiconductor protection switch 12 to zero. The hybrid protection switch device 30 has another mechanical interrupter 22. Another mechanical interrupter 22 is arranged in series with the semiconductor protection switch 12. Another mechanical interrupter 22 is arranged in series with the mechanical interrupter 10. Another mechanical interrupter 22 is arranged in series with the varistor 32. Another mechanical interrupter 22 is configured to trip with a time offset relative to the mechanical interrupter 10. Another mechanical interrupter 22 is configured to trip slower than the mechanical interrupter 10. Another mechanical interrupter switch 22 is provided to create and maintain galvanic isolation of the circuit.

[0042] The hybrid contactor 28 has a maintenance switch 38. The maintenance switch 38 is arranged to allow disconnection of the circuit monitored by the hybrid protection switch device 30. The maintenance switch 38 is arranged to disconnect the circuit without load. The maintenance switch 38 can be disconnected, for example, to achieve maintenance of the circuit. The maintenance switch 38 can be operated manually or automatically. The maintenance switch 38 is configured to be separate from the hybrid protection switch device 30. The mechanical interrupter 10 is configured to have no coil at all. The hybrid protection switch device 30 is configured to have no choke. The hybrid contactor 28 is configured to have no choke.

[0043] Figure 2a and Figure 2b A schematic diagram of a part of a hybrid protection switch device 30 is shown, which includes a mechanical interrupter switch 10 and a further mechanical interrupter switch 22. The mechanical interrupter switch 10 has a tripping element 14. The tripping element 14 is of a magnetically sensitive type. The tripping element 14 is arranged in the vicinity of a current-conducting conductor part 40 of the circuit. The tripping element 14 is arranged in parallel with the current-conducting conductor part 40. The tripping element 14 is arranged in such a way that the longitudinal extension directions of the tripping element 14 and the conductor part 40 extend at least substantially parallel to each other. The tripping element 14 is configured to produce an interruption of the circuit by a change in shape. The tripping element 14 is configured to produce an interruption of the circuit by a change in length. The tripping element 14 is configured to cause a switch that physically separates the circuit by a change in length and / or a change in shape. In Figure 2a and Figure 2b , a switch is shown as an example of a toggle switch. The trip element 14 is partially composed of a magnetic shape memory alloy 16. The trip element 14 can alternatively be composed entirely or almost entirely of a magnetic shape memory alloy 16. The trip element 14 is oriented and / or arranged in such a way that the magnetic field caused by the change of the current in the conductor 40 is guided by the trip element 14 in such a way that a change in the shape of the magnetic shape memory alloy 16 is caused. The magnetic shape memory alloy 16 is configured as a magnetic high-temperature shape memory alloy. Figure 2a In the embodiment, the trip element 14 is in an undeformed state. Figure 2b In the embodiment, the trip element 14 is in a deformed state. Figure 2b In the embodiment shown in FIG. 1 , the trip element 14 has an elongated shape compared to the undeformed state. Figure 2a The mechanical interrupter switch 10 is shown in normal operation. Figure 2b The state of the mechanical interrupter switch 10 in the event of a fault is shown.

[0044] Figure 2a The state of the other mechanical interrupter switch 22 in normal operation is shown. The other mechanical interrupter switch 22 is closed. Figure 2bThe state of another mechanical interrupter switch 22 in a fault situation is shown. Another mechanical interrupter switch 22 is disconnected. Another mechanical interrupter switch 22 has a tripping element 26, which is at least partially composed of a magnetic shape memory alloy 16. The tripping element 14 of the mechanical interrupter switch 10 also represents the tripping element 26 of the other mechanical interrupter switch 22. Due to the change in the length of the tripping element 14, the disconnection of the other mechanical interrupter switch 22 is also triggered. Alternatively, the other mechanical interrupter switch 22 can also be disconnected by another tripping element separate from the tripping element 14, in particular in a functional manner comparable to the tripping element 4.

[0045] The hybrid protection switch device 30 has a delay unit 24. The delay unit 24 is configured to delay the action of the tripping elements 14, 26 on the other mechanical interrupter 22 in time relative to the action of the tripping elements 14, 26 on the mechanical interrupter 10. The delay unit 24 is exemplarily formed by a toggle switch spaced apart from the other mechanical interrupter 22. Alternative designs of the delay unit 24 that perform the same task according to the invention are conceivable and can be derived from the professional knowledge of a person skilled in the art.

[0046] Figure 3a and Figure 3b Schematically shown is a top view of the mechanical interrupter switch 10. The curve of the magnetic field generated by the conductor 40 is indicated by magnetic field lines 42. The magnetic field lines 42 cross the trip element 14 perpendicularly to its longitudinal extension. Figure 3a The mechanical interrupter switch 10 shown is constructed without magnetic flux conducting components other than the magnetic shape memory alloy 16 of the trip element 14. However, alternatively, as Figure 3b As shown, the conductor 40 may also be surrounded by a flux-conducting collar 44 into which the trip element 14 is inserted.

[0047] like Figure 3a and Figure 3b As shown in the example, the mechanical interrupter switch 10 can also include a thermal-sensitive trip element 26 in addition to the magnetic-sensitive trip element 14. The thermal-sensitive trip element 26 is configured to interrupt the circuit when overloaded. The thermal-sensitive trip element 26 is configured to undergo a length change when a limit temperature is exceeded and to disconnect the mechanical interrupter switch 10 in this case, in particular similar to the function of the magnetic-sensitive trip element 14. The thermal-sensitive trip element 26 is at least mostly, preferably completely or almost completely, composed of a thermal shape memory alloy 52.

[0048] Figure 4A magnetically sensitive trip element 14 having a schematic internal structure is shown. The trip element 14 includes a plurality of twin boundaries 18, 20. The twin boundaries 18, 20 can be produced by (mechanical) surface treatment of the magnetic shape memory alloy 16. The twin boundaries 18, 20 are coherently movable. Here, the distance 46 between adjacent twin boundaries 18, 20 of the trip element 14 is less than 300 μm, preferably less than 150 μm.

[0049] Figure 5 A schematic flow chart of a method for operating a hybrid protective switch device 30 is shown. In at least one method step 48, the mechanical interrupter 10 is actuated in the event of an overcurrent by a change in shape of the magnetic shape memory alloy 16. In at least one further method step 50, the mechanical interrupter 10 is actuated in the event of an overload by a change in shape of the thermal shape memory alloy 52.

[0050] Figure 6 A time-dependent current curve 58 through the various components of the hybrid contactor 28 is schematically shown. Figure 6 The basic functioning mode of the hybrid contactor 28 is briefly described. Figure 6 The time is plotted on the abscissa 54 in FIG. The times t1 to t5 are particularly marked on the abscissa 54. Figure 6 In FIG. 5 , the current is plotted on the ordinate 56 , since the current would occur at the components of the hybrid contactor 28 in the event of a fault. Figure 63 shows the following current curves 58 from top to bottom: (a) the total current through the hybrid contactor 28; b) the current through the mechanical interrupter 10; c) the current through the semiconductor protection switch 12 and d) the current through the varistor 32. From the beginning to the time point t1, the current corresponds to the nominal value of normal operation and flows completely through the path of the mechanical interrupter 10 that is closed in normal operation. At the time point t1, a fault condition occurs. The fault condition causes a rapid increase in the current flowing through the mechanical interrupter 10. The magnetic field generated in this case causes the deformation of the magnetic shape memory alloy 16 of the trip element 14 and thus causes the disconnection of the mechanical interrupter 10. An arc and an arc voltage associated therewith are generated by opening the mechanical interrupter 10. The arc voltage also appears at the semiconductor protection switch 12 at the same time. From the time point t2 when the minimum voltage at the semiconductor protection switch 12 is exceeded, the semiconductor protection switch 12 allows the current to flow. The time period between the time points t1 and t2 is called the disconnection time 36. At the time point t3, the current is completely commutated from the mechanical interrupter 10 to the semiconductor protection switch 12. After the current to the semiconductor protection switch 12 is completely commutated, the mechanical interrupter switch 10 is completely opened. At the time point t4, the semiconductor protection switch 12 is closed / opened. This occurs as soon as the mechanical interrupter switch 10 is safely opened to a sufficient width. The current in the path of the semiconductor protection switch 12 thus drops almost suddenly to zero. The current is completely commutated to the varistor 32. By the time point t5, the varistor 32 conducts the current to zero. After the time point t5, the other mechanical interrupter switch 22 is opened with a time delay.

[0051] Figure 7 and Figure 8 Each shows a schematic circuit diagram of a hybrid contactor 28 ′, 28 ″ having additional elements for opening the circuit in a controlled manner under load. Figure 7 1 shows a design of a hybrid contactor 28' comprising an electromagnet 34'. The electromagnet 34 is designed and / or arranged so that the magnetic field generated by the electromagnet 34 can cause the actuation of the trip element 14 of the mechanical interrupter switch 10. When the mechanical interrupter switch 10 is to be opened in a controlled manner, the electromagnet 34 is controlled and generates a magnetic field, which produces a change in the shape of the trip element 14 corresponding to a short circuit situation. Figure 81 shows a design of a hybrid contactor 28 ', which includes a capacitor 60, which is electrically connected in parallel with the mechanical interrupter switch 10 and can be discharged by means of a switch 62 of the hybrid protective switch device 30. The capacitor 60 is charged in normal operation. When the switch 62 is closed, the capacitor 60 is suddenly discharged and generates a high current at least for a short time. Due to the high current gradient when the capacitor 60 is discharged, a magnetic field is generated that is large enough to actuate the trip element 14 of the mechanical interrupter switch 10. When the mechanical interrupter switch 10 is to be opened in a controlled manner, the switch 62 is closed and generates a magnetic field by discharging the capacitor 60, which produces a change in the shape of the trip element 14 that is equivalent to an actual short-circuit situation. Figure 7 The electromagnet 34 and Figure 8 The capacitors 60 of the design of the embodiment are arranged to allow the circuit monitored by the hybrid protective switch device 30 to be disconnected in a controlled manner.

[0052] Description of reference numerals:

[0053] 10 Mechanical interrupter switch

[0054] 12Semiconductor protection switch

[0055] 14 Tripping element

[0056] 16 Magnetic shape memory alloy

[0057] 18 Twin Boundary

[0058] 20Twin Boundary

[0059] 22 Another mechanical interrupter switch

[0060] 24 delay units

[0061] 26 Tripping element

[0062] 28 Hybrid contactor

[0063] 30 Hybrid protection switchgear

[0064] 32 Rheostat

[0065] 34 Electromagnet

[0066] 36 Disconnection time

[0067] 38 Maintenance switch

[0068] 40 conductor parts

[0069] 42 Magnetic Field Lines

[0070] 44 shaft collar

[0071] 46Distance

[0072] 48 Methods and Steps

[0073] 50 Methods and Steps

[0074] 52 Thermal shape memory alloy

[0075] 54 horizontal axis

[0076] 56 vertical coordinate

[0077] 58 Current Curve

[0078] 60 Capacitors

[0079] 62 switches

Claims

1. A hybrid protection switch device (30), in particular a DC hybrid protection switch device, comprising at least one mechanical interrupter switch (10) and at least one semiconductor protection switch (12), in particular a semiconductor relay, electrically connected in parallel with the mechanical interrupter switch (10), characterized in that: The mechanical interrupter switch (10) has, in particular, a magnetically sensitive tripping element (14) which is at least partially composed of a magnetic shape memory alloy (16).

2. The hybrid protection switch device (30) according to claim 1, characterized in that: The mechanical interrupter switch (10) has a disconnection time (36) of less than 400 μs, preferably less than 200 μs, in the event of a trip.

3. The hybrid protection switch device (30) according to claim 1 or 2, characterized in that: The trip element (14), in particular a trip element (14) produced by (mechanical) surface treatment of the magnetic shape memory alloy (16), comprises a plurality of coherently movable twin boundaries (18, 20).

4. The hybrid protection switch device (30) according to claim 3, characterized in that: The distance (46) between adjacent twin boundaries (18, 20) of the trip element (14) is less than 300 μm, preferably less than 150 μm.

5. The hybrid protection switch device (30) according to any one of the preceding claims, characterized in that The mechanical interrupter switch (10) is designed without a coil.

6. A hybrid protection switch device (30) according to any one of the preceding claims, characterized in that No choke structure.

7. A hybrid protection switch device (30) according to any one of the preceding claims, characterized in that The mechanical interrupter switch (10) is constructed at least substantially free of magnetic flux conducting components other than the magnetic shape memory alloy (16) of the trip element (14).

8. A hybrid protection switch device (30) according to any one of the preceding claims, characterized in that At least one further mechanical interrupter switch (22) is arranged in series with at least the semiconductor protection switch (12), the further mechanical interrupter switch (22) being configured to trip in a time-shifted and / or slower manner relative to the mechanical interrupter switch (10).

9. The hybrid protection switch device (30) according to claim 8, characterized in that: The further mechanical interrupter switch (22) has a tripping element (26) which is at least partially composed of a magnetic shape memory alloy (16).

10. The hybrid protection switch device (30) according to claim 9, characterized in that: The trip element (14) of the mechanical interrupter switch (10) also represents the trip element (26) of the other mechanical interrupter switch (22).

11. The hybrid protection switch device (30) according to claim 10, characterized in that A delay unit (24) is arranged to delay the action of the trip element (14, 26) on the other mechanical interrupter (22) in time relative to the action of the trip element (14, 26) on the mechanical interrupter (10).

12. The hybrid protection switch device (30) according to any one of the preceding claims, characterized in that The magnetic shape memory alloy (16) is configured as a magnetic high temperature shape memory alloy.

13. The hybrid protection switch device (30) according to any one of the preceding claims, characterized in that The mechanical interrupter switch (10) in particular comprises a thermally sensitive tripping element (26) in addition to the magnetically sensitive tripping element (14).

14. A hybrid contactor (28), in particular a DC hybrid contactor, comprising a hybrid protection switch device (30) according to any one of the preceding claims and at least one varistor (32) electrically connected in parallel with the hybrid protection switch device (30).

15. The hybrid contactor (28) according to claim 14, characterized in that An electromagnet (34) and / or a capacitor (60) electrically connected in parallel with the mechanical interrupter switch (10) and dischargeable by means of a switch (62), the electromagnet (34) and the capacitor (60) each being at least configured to allow a circuit monitored by the hybrid protective switchgear (30) to be disconnected in a controlled manner.

16. A method for operating a hybrid protection switch device (30), preferably according to any one of claims 1 to 13, in particular a DC hybrid protection switch device, the hybrid protection switch device (30) having at least one mechanical interrupter switch (10) and at least one semiconductor protection switch (12), in particular a semiconductor relay, electrically connected in parallel to the mechanical interrupter switch (10), characterized in that: The mechanical interrupter switch (10) is actuated by a change in shape of a magnetic shape memory alloy (16) in the event of an overcurrent.

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