DE102022111392A1 - Hybrid circuit breaker device, hybrid contactor and method - Google Patents

Abstract

The invention is based on a hybrid circuit breaker device (30), in particular a DC hybrid circuit breaker device, with at least one mechanical interruption switch (10) and with at least one semiconductor circuit breaker (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 a trigger element (14), in particular a magnetic field-sensitive one, which is at least partially formed from a magnetic shape memory alloy (16).

Description

State of the art

The invention relates to a hybrid circuit breaker device according to the preamble of claim 1, a hybrid contactor according to claim 15 and a method according to claim 16.

In particular, from a contribution to the 30th International Conference on Electrical Contacts by the author Wolfgang Hauer with the title “New Switching Technology for DC Grids” there is already a hybrid circuit breaker device with at least one mechanical interruption switch and with at least one semiconductor circuit breaker connected electrically in parallel to the mechanical interruption switch known.

The object of the invention is, in particular, to provide a generic device with advantageous properties with regard to protection against overcurrent. The object is achieved according to the invention by the features of patent claims 1, 15 and 16, while advantageous refinements and developments of the invention can be found in the subclaims.

Advantages of the invention

The invention is based on a hybrid circuit breaker device, in particular a DC hybrid circuit breaker device, with at least one mechanical interruption switch and with at least one semiconductor circuit breaker, in particular a semiconductor relay, which is electrically connected in parallel to the mechanical interruption switch.

It is proposed that the mechanical interruption switch has a trigger element, in particular a magnetic field-sensitive one, which is at least partially formed from a magnetic shape memory alloy (also known as MSM material = Magnetic Shape Memory). This can advantageously improve protection against overcurrent, in particular by allowing a particularly high response speed/triggering speed of the mechanical interruption switch to be achieved. A fast-reacting and therefore safe and also cost-effective overcurrent protection can advantageously be achieved, which is particularly suitable for direct current networks, in which, in the event of a fault, especially in comparison to alternating current networks, very high current rise rates (in ranges of up to 100 A / ps) with very high currents (in ranges of up to 10 kA) can occur. The high speed can advantageously be achieved with low electrical losses in nominal operation, as can occur, for example, with a contactor based purely on solid-state relays.

A “hybrid circuit breaker device” is to be understood as meaning, in particular, a component, in particular a functional component, in particular a construction and/or functional component, of a hybrid contactor. A “hybrid contactor” is to be understood in particular as a hybrid circuit breaker, which is intended to bring about an emergency shutdown of a current flow within a circuit via the interaction of mechanical and semiconductor-based switching components. In particular, the hybrid circuit breaker device is intended for use in and/or for installation in a hybrid contactor. The hybrid contactor is advantageously intended to protect the circuit, equipment connected to it and/or its lines from an overload and/or an overcurrent and/or a short-circuit current. “Provided” is intended to mean, in particular, specifically programmed, designed and/or equipped. The fact that an object is intended for a specific function should be understood in particular to mean that the object fulfills and/or executes this specific function in at least one application and/or operating state. A DC hybrid circuit breaker device is intended to interrupt a direct current circuit. In particular, the mechanical interruption switch is intended to generate an interruption of the circuit at least through a mechanical movement of a component, preferably through a mechanical opening of an electrical contact of the circuit. In particular, the semiconductor protective switch is intended to generate an interruption of the circuit at least by electrically activating a semiconductor component. For example, the semiconductor protective switch can be designed as an insulated gate electrode (Insulated-Gate Bipolar Transistor, IGBT for short) or as a metal-oxide-semiconductor field-effect transistor (MOSFET for short). be. In particular, the semiconductor circuit breaker forms a semiconductor interruption switch and vice versa.

In particular, a tripping event in which the circuit is opened by the hybrid circuit breaker device includes an overcurrent event, in particular a short circuit event and/or overload event. In particular, the tripping event, particularly in the event of a short circuit, can include a magnetic tripping event. In addition, the triggering event, especially in an over load case, include a thermal trip case. In this case, a triggering element is provided both for the thermally induced deformation, in particular in an overload case, and for the magnetically induced deformation, in particular in a short circuit case. Particularly preferably, the deformation includes at least a change in length of the triggering element, in particular along its longitudinal axis. The trigger element is advantageously intended to generate a movement and/or a force to open the circuit, in particular directly, due to the deformation. The movement to open the circuit is advantageously a stroke and/or a change in the longitudinal extent of the triggering element. It is also conceivable that the triggering element is intended to generate the movement and/or the force for opening the circuit due to a deformation in a direction angular and/or perpendicular to the longitudinal axis of the triggering element. The longitudinal direction runs in particular at least essentially parallel to a main extension direction of the triggering element, whereby a “main extension direction” of an object is to be understood in particular as a direction which runs parallel to a longest edge of a smallest geometric cuboid, which just completely encloses the object. In particular, the trigger element is intended to actuate a switch, for example a toggle switch, which opens electrical contacts of the circuit in the open state. In particular, the current in the tripping event is greater than a rated current, in particular a standard household or industrial (DC) rated current. The trip unit can be designed for any rated current, for example for (DC) rated currents of 63 A, 100 A, 200 A, etc., but also for significantly larger or significantly smaller rated currents. In particular, the current in the overload case is greater than the nominal current, preferably over at least a period of time in the range of seconds or minutes. For example, in alternating current circuits, the overload case occurs at currents that are at least in a range above 1.15 times, preferably 1.45 times the rated current. It is assumed that similar limit values apply to DC circuits as to AC circuits. Furthermore, the current in the event of a short circuit is in particular greater than the current in the event of an overload. In particular, in alternating current circuits, the short circuit occurs at currents that are at least in a range above 5 times, preferably 10 times, the nominal current. Even in the event of a short circuit, it is assumed that similar limit values apply to DC circuits as to AC circuits.

In particular, the triggering element is designed separately from conductor tracks of the circuit to be monitored. Preferably, the triggering element is at least partially, preferably completely, arranged in a close area of a current-carrying conductor section of the circuit to be monitored. In this context, a “close range” is to be understood in particular as an area which is formed from points which are at most ten times, preferably at most seven times, preferably at most five times and particularly preferably at most three times a line diameter of the current-carrying conductor section are arranged away from the current-carrying conductor section. In particular, the points forming the close range each have a distance of at most 10 mm, preferably at most 5 mm and particularly preferably at most 3 mm from the conductor section. In particular, the triggering element is arranged relative to the current-carrying conductor section of the circuit to be monitored in such a way that a magnetic field generated at least temporarily by a strong increase in current runs/is guided through the triggering element. Preferably, the triggering element and the current-carrying conductor section of the circuit to be monitored extend at least essentially parallel to one another, at least in the close range. “Substantially parallel” is to be understood here in particular as an alignment of a direction relative to a reference direction, in particular in a plane, with the direction having a deviation from the reference direction, in particular less than 8°, advantageously less than 5° and particularly advantageously less than 2°. Preferably, the current-carrying conductor section of the circuit to be monitored is different from a part of an electrical coil, in particular straight or curved, preferably not wound and not multi-threaded.

In particular, the current-carrying conductor section of the circuit to be monitored is designed as a single conductor. In particular, the triggering element is intended to react to (strong) magnetic field changes that are generated by the current-carrying conductor section of the circuit to be monitored, in particular by a change in length. It is also conceivable that the conductor section heats up in the tripping event, in particular due to a current in the circuit to be monitored that exceeds the rated current, with the resulting thermal radiation being able to be absorbed by the tripping element and thereby causing the optional further thermal tripping event. Particularly preferably, in the circuit to be monitored, in the event of a trip, particularly in the event of a short circuit, current flowing in the conductor section creates a triggering magnetic field for the triggering element. In particular, the triggering element can be influenced and/or deformed by means of the conductor section and/or by means of a magnetic field generated by means of the conductor section, in particular in the event of triggering. The trigger element can be plunger-shaped, elongated, rod-shaped, pin-shaped and / or cylindrical. In particular, a main deformation axis is the axis of greatest deformation of the triggering element. Preferably, the main deformation direction is arranged at least substantially parallel to the longitudinal axis of the trigger element. The trigger element preferably has an at least substantially constant cross section. The trigger element is preferably designed in one piece.

The trigger element is advantageously designed as a solid body. However, it is also conceivable that the triggering element, in particular at least in sections, is designed as a hollow body, for example as a hollow cylinder, and/or as a solid body with recesses and/or cavities or the like. The triggering element is preferably formed to at least a large extent, in particular completely, from the magnetic shape memory alloy. The hybrid switch device particularly preferably has a single trigger element. However, it is also conceivable that the hybrid switch device has a plurality of trigger elements, in particular identical or differently designed trigger elements. The fact that an object has an “at least essentially constant cross-section” should be understood in particular to mean 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, a minimum area of a difference area, which is formed when the cross sections are placed one on top of the other, a maximum of 20%, advantageously a maximum of 10% and particularly advantageously a maximum of 5% of the surface area of the larger of the two cross sections. The expression “to at least a large part” should be understood to mean in particular 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 also completely.

The magnetic shape memory alloy preferably contains nickel, manganese and gallium. The magnetic shape memory alloy is particularly preferably a nickel-manganese-gallium alloy. Alternatively, the magnetic shape memory alloy could also be an iron-palladium alloy and/or an iron-palladium-containing alloy. In addition, the magnetic shape memory alloy could also be designed as a foam and / or as a composite structure and / or as granules and / or as a porous material, it being conceivable, in particular in the case of a composite material, that nickel, manganese and / or gallium components in one Matrix can be embedded. In addition, the magnetic shape memory alloy could be monocrystalline. The trigger element is preferably designed as a single crystal made of the magnetic shape memory alloy. It is also conceivable that the trigger element is composed of several, in particular several, for example two or three or four or five individual single crystals. However, it is also conceivable that the magnetic shape memory alloy is polycrystalline.

In particular, the mechanical interruption switch is intended to commutate the current to the semiconductor circuit breaker at the start of an opening process of the mechanical interruption switch in the event of an overcurrent. In particular, a voltage of an arc that ignites when the mechanical interruption switch is opened can optionally be used for commutation. The arc is then extinguished in particular by commutation of the current.

Preferably, the triggering event is non-destructive and repeatable after all components of the hybrid circuit breaker device have been reset. Contact erosion can advantageously be avoided.

It is also proposed that the mechanical interruption switch has an opening time of less than 400 µs, preferably less than 200 µs, when triggered. This can advantageously enable a particularly quick reaction. Suitability for DC networks can be advantageously achieved. A particularly high level of security can advantageously be achieved. By accelerating the mechanical opening of the hybrid contactor, the use of smaller semiconductor circuit breakers and/or varistors in the other branches of the hybrid contactor can advantageously be made possible, in particular since a comparatively smaller overall current has to be extinguished by the hybrid contactor. In this case, the “opening time” of the mechanical interruption switch is intended to mean in particular a time that elapses between the occurrence of a fault current, e.g. a short circuit, until a partial opening of the mechanical interruption switch, at which there is enough voltage due to the arc created during the opening the electronics of the semiconductor interrupter switch, in particular for commutation of the current to the branch of the hybrid circuit breaker device the semiconductor circuit breaker. In particular, the opening time can also include the time from the occurrence of the fault current (beginning of the opening movement of the triggering element) until a maximum current value is reached in the branch of the hybrid circuit breaker device with the mechanical circuit breaker (partial opening, in which the resulting arc voltage corresponds to an activation voltage of the semiconductor circuit breaker ) can be understood. In particular, the opening time can also be understood as the time from the occurrence of the fault current until a current flow begins through the branch of the hybrid circuit breaker device with the semiconductor circuit breaker. In particular, at least essentially the same voltage is applied to components of a circuit that are electrically connected in parallel. So if the voltage in the branch of the hybrid circuit breaker device with the mechanical circuit breaker increases, the voltage at the semiconductor circuit breaker also increases at the same time, so that above a certain voltage the semiconductor circuit breaker is “unlocked”.

In addition, it is proposed that the triggering element, in particular produced by a (mechanical) surface treatment of the magnetic shape memory alloy, comprises a plurality of coherently movable twin boundaries. As a result, a high contraction or expansion speed of the trigger element can advantageously be achieved. A particularly high level of security can advantageously be achieved. In particular, each twin boundary of a magnetic shape memory alloy has a maximum movement speed, which depends, among other things, on a specific microstructure of the material and/or a configuration of the twin boundaries. By having a plurality of twin limits, the achievable maximum movement speed can be advantageously increased, possibly even to such an extent that the limitation of the movement speed is dominated by an unavoidable mass inertia of the volume of the triggering element to be moved. In particular, additional twin boundaries can be created by suitable surface treatment of the magnetic shape memory alloy, such as roughening a surface of the magnetic shape memory alloy, shot peening the surface of the magnetic shape memory alloy, or the like.

If the distances between adjacent twin boundaries of the triggering element are smaller than 300 µm, preferably smaller than 150 µm and preferably smaller than 100 µm, a particularly high/optimal movement speed for the deformation of the triggering element can advantageously be achieved. In particular, the distance between the adjacent twin boundaries is measured in the longitudinal direction of the trigger element.

Furthermore, it is proposed that the mechanical interruption switch is designed to be coil-free. This can advantageously reduce the complexity of the hybrid circuit breaker device, in particular of the hybrid contactor, preferably of the mechanical interruption switch. A simple and/or cost-effective construction can advantageously be achieved. A particularly small design of the hybrid circuit breaker device, in particular of the hybrid contactor, can advantageously be achieved.

If, in addition, the hybrid circuit breaker device has a choke coil, in particular completely, which is free from a choke coil connected upstream of the mechanical interrupter switch, for example, complexity can advantageously be further reduced, whereby costs can be particularly advantageously reduced. The entire hybrid contactor is preferably free of any inductors/coils. Advantageously, due to the high speed of the mechanical interruption switch, a choke coil for additionally delaying a current increase in the event of a fault is unnecessary. A particularly small design of the hybrid circuit breaker device, in particular of the hybrid contactor, can advantageously be achieved. A further advantage of the coil-free design, in particular the elimination of the choke coil, is, in addition to the reduced costs and the reduced installation space, also a reduction in power loss in nominal operation (also in direct current circuits).

Furthermore, it is proposed that the mechanical interruption switch, apart from the magnetic shape memory alloy of the triggering element, is designed to be at least essentially free of magnetic flux-conducting components. As a result, an inductive resistance can advantageously be minimized, particularly in the event of a short circuit, whereby a time constant and/or thermal losses can be advantageously reduced, so that a particularly high reaction speed can be achieved. In particular, the magnetic fields generated by the overcurrent in the event of a fault are already high enough, especially in the case of direct current, to reliably switch the tripping element. In particular, apart from the magnetic shape memory alloy, the triggering element is designed to be free of further magnetic flux-conducting components.

In addition, it is proposed that the hybrid circuit breaker device has at least one further mechanical interrupter arranged in series at least with the semiconductor circuit breaker has a curing switch, which is intended to be triggered with a time delay and/or slower than the mechanical interruption switch. As a result, a particularly high level of security can advantageously be achieved. In particular, the further mechanical interruption switch is intended to produce a galvanic isolation of the circuit (which cannot be achieved by the semiconductor circuit breaker and/or the varistor alone). In particular, the requirements for the dynamics of the further mechanical interruption switch are significantly lower compared to the mechanical interruption switch. In particular, the further mechanical interruption switch is also arranged in series with the mechanical interruption switch. In particular, the further mechanical interruption switch forms an isolation switch of the hybrid circuit breaker device.

If the further mechanical interruption switch has a trigger element which is at least partially formed from a magnetic shape memory alloy, a particularly advantageous circuit of the further mechanical interruption switch can be achieved. A simple construction can advantageously be achieved.

If the triggering element of the mechanical interruption switch also represents the triggering element of the further mechanical interruption switch, a particularly high level of compactness and/or cost-effectiveness of the hybrid circuit breaker device can advantageously be achieved. In addition, a small construction can advantageously be achieved.

It is also proposed that the hybrid circuit breaker device has a delay unit which is intended to time-delay an effect of the triggering element on the further mechanical interruption switch relative to an effect of the triggering element on the mechanical interruption switch. The delay unit can, for example, be designed as a simple spacing of the further mechanical interruption switch from the triggering element or from a further component of the hybrid circuit breaker device (e.g. the opening conductor section) actuated by the triggering element. In this way, the further mechanical interruption switch is only actuated when the triggering element has already expanded somewhat and/or when the further component of the hybrid circuit breaker device actuated by the triggering element has already moved somewhat.

In addition, it is proposed that the magnetic shape memory alloy is designed as a magnetic high-temperature shape memory alloy. This advantageously enables reliable operation of the hybrid circuit breaker device in a large operating temperature range. A high level of security can advantageously be achieved. The magnetic shape memory alloy preferably has at least one, in particular exactly one, first transformation temperature, in particular from at least one martensitic to at least one austenitic phase. Particularly preferably, the magnetic shape memory alloy has at least one, in particular exactly one, second transformation temperature, in particular from at least one ferromagnetic to at least one paramagnetic phase. The first conversion temperature and the second conversion temperature are advantageously selected such that they are at least higher than temperatures that the triggering element assumes in a normal operating state, in particular when there is no triggering event. 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/ lay. This can advantageously prevent incorrect triggering, for example due to an increased ambient temperature.

It is also proposed that the mechanical interruption switch comprises a thermosensitive triggering element, in particular in addition to the magnetic field-sensitive triggering element. This can advantageously provide additional overload protection. A particularly high level of security can advantageously be achieved. In particular, the thermosensitive triggering element is made of a thermal shape memory alloy, such as Nitinol. It is conceivable that the thermal shape memory alloy and the magnetic shape memory alloy, when connected to one another, form a common triggering element or are designed as two separate triggering elements, for example in the form of two adjacent or interconnected strips. In addition, it is also conceivable that the trigger element is made of a material that has a magnetic shape memory effect, in particular a magnetic high-temperature shape memory effect, and a thermal shape memory effect. The trigger element is preferably designed to be thermally and magnetically variable in shape. A “thermally and/or magnetically shape-changing material” is intended to mean, in particular, a material which is produced by increasing the temperature, in particular by supplying thermal energy Energy, and / or can be influenced by a, in particular external, magnetic field and is advantageously provided in at least one operating state to change at least one material property and / or a shape at least depending on a temperature of the material and / or at least depending on the magnetic field. However, it is also conceivable that the hybrid circuit breaker device is designed without a thermosensitive trigger element.

Furthermore, the hybrid contactor, in particular a DC hybrid contactor, is proposed with the hybrid circuit breaker device and with at least one varistor electrically connected in parallel to the hybrid circuit breaker device. This makes it possible to achieve advantageous properties in terms of speed and/or security. The hybrid contactor is advantageously significantly faster than a mechanical circuit breaker, which, for example, has power interruption times in the millisecond range, and at the same time significantly cheaper to manufacture and/or maintain than pure semiconductor line switches. “DC” is intended to mean in particular direct current. In particular, the varistor is electrically connected in parallel to the mechanical interruption switch. In particular, the varistor is electrically connected in parallel to the semiconductor protective switch. In particular, the varistor is intended to lead the current to zero (“slowly”) after being extinguished by the semiconductor circuit breaker.

In addition, it is proposed that the hybrid contactor has an electromagnet and/or a capacitor that is electrically connected in parallel to the mechanical interrupter switch and can be discharged by means of a switch, each of which is at least intended to allow a controlled opening of the circuit monitored by the hybrid circuit breaker device. This can advantageously achieve a controlled shutdown of the hybrid contactor, especially under load, preferably without contact erosion. In particular, the electromagnet, preferably the magnetic field generated by the electromagnet, is intended to trigger, preferably deform, the triggering element of the mechanical interruption switch in a controlled manner. In particular, the capacitor is intended to generate a high discharge current when the switch is closed, by means of which a short circuit can be simulated, so that the triggering element is triggered and the circuit is opened.

Furthermore, a method for operating the hybrid circuit breaker device, in particular the DC hybrid circuit breaker device, with at least one mechanical interruption switch and with at least one semiconductor circuit breaker, in particular a semiconductor relay, connected electrically in parallel to the mechanical interruption switch, the mechanical interruption switch being activated in the event of an overcurrent by a Shape change of a magnetic shape memory alloy is operated, proposed. This can advantageously improve protection against overcurrent, in particular by allowing a particularly high response speed/triggering speed of the mechanical interruption switch to be achieved. Advantageously, fast-reacting and therefore safe and also cost-effective overcurrent protection can be achieved.

The hybrid circuit breaker 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 application and embodiment described above. In particular, the hybrid circuit breaker device according to the invention, the hybrid contactor according to the invention and the method according to the invention can have a number of individual elements, method steps, components and units that deviate from the number of individual elements, method steps, components and units mentioned herein in order to fulfill a function of operation described herein.

drawings

Further advantages result from the following drawing description. Exemplary embodiments of the invention are shown in the drawings. The drawings, description and claims contain numerous features in combination. The person skilled in the art will also expediently consider the features individually and combine them into further sensible combinations.

• 1 eine schematische Schaltbild-Darstellung eines Hybridschützes mit einer Hybridschutzschaltervorrichtung,
• 2a eine schematische Darstellung eines Teils der Hybridschutzschaltervorrichtung in einem geschlossenen Zustand,
• 2b eine schematische Darstellung eines Teils der Hybridschutzschaltervorrichtung in einem geöffneten Zustand,
• 3a schematisch eine Oberansicht eines mechanischen Unterbrechungsschalters der Hybridschutzschaltervorrichtung,
• 3b schematisch eine Oberansicht eines leicht abgewandelten mechanischen Unterbrechungsschalters der Hybridschutzschaltervorrichtung,
• 4 schematisch ein magnetsensitives Auslöseelement des mechanischen Unterbrechungsschalters mit einer schematischen internen Struktur,
• 5 ein schematisches Ablaufdiagramm eines Verfahrens zu einem Betrieb der Hybridschutzschaltervorrichtung,
• 6 schematisch zeitabhängige Stromverläufe durch Komponenten des Hybridschützes,
• 7 eine schematische Schaltbild-Darstellung des Hybridschützes mit der Hybridschutzschaltervorrichtung und mit einem zusätzlichen Elektromagnet und
• 8 eine schematische Schaltbild-Darstellung des Hybridschützes mit der Hybridschutzschaltervorrichtung und mit einem zusätzlichen Kondensator.

Show it:

• 1 a schematic circuit diagram representation of a hybrid contactor with a hybrid circuit breaker device,
• 2a a schematic representation of a part of the hybrid circuit breaker device in a closed state,
• 2 B a schematic representation of a part of the hybrid circuit breaker device in an open state,
• 3a schematically a top view of a mechanical interrupter switch of the hybrid circuit breaker device,
• 3b schematically a top view of a slightly modified mechanical interrupter switch of the hybrid circuit breaker device,
• 4 schematically a magnet-sensitive trigger element of the mechanical interrupter switch with a schematic internal structure,
• 5 a schematic flowchart of a method for operating the hybrid circuit breaker device,
• 6 schematic time-dependent current curves through components of the hybrid contactor,
• 7 a schematic circuit diagram representation of the hybrid contactor with the hybrid circuit breaker device and with an additional electromagnet and
• 8th a schematic circuit diagram representation of the hybrid contactor with the hybrid circuit breaker device and with an additional capacitor.

Description of the exemplary embodiments

The 1 shows a schematic circuit diagram representation of a hybrid contactor 28. The hybrid contactor 28 is designed as a DC hybrid contactor. The hybrid contactor 28 is intended for a quick-response, automatic interruption of a circuit/current flow in the event of a fault. The hybrid contactor 28 includes a hybrid circuit breaker device 30. The hybrid circuit breaker device 30 is designed as a DC hybrid circuit breaker device. The hybrid circuit breaker device 30 comprises a mechanical interruption switch 10. The mechanical interruption switch 10 has an opening time 36 in the event of a trip (cf. 4 ) of less than 400 µs, preferably even less than 200 µs. The mechanical interruption switch 10 is intended to open the electrical contact particularly quickly and/or automatically in the event of a fault. When the mechanical interruption switch 10 is opened, a short arc is created. When the mechanical interruption switch 10 is opened, the electrical voltage dropped across the mechanical interruption switch 10 increases. The hybrid circuit breaker device 30 includes a semiconductor circuit breaker 12. The semiconductor circuit breaker 12 is designed as a semiconductor relay (eg MOSFET or IGBT). The semiconductor circuit breaker 12 is electrically connected in parallel to the mechanical interruption switch 10. Due to the electrical parallel connection of the semiconductor circuit breaker 12 to the mechanical circuit breaker 10, the electrical voltage dropped across the semiconductor circuit breaker 12 always corresponds to the electrical voltage dropped across the mechanical circuit breaker 10. The semiconductor circuit breaker 12 is intended to take over the current from the opening mechanical interruption switch 10 above a certain minimum arc voltage.

The hybrid contactor 28 includes a varistor 32. The varistor 32 is electrically connected in parallel to the hybrid circuit breaker device 30. The varistor 32 is electrically connected in parallel to the mechanical interrupter switch 10. The varistor 32 is electrically connected in parallel to the semiconductor circuit breaker 12. Due to the electrical parallel connection of the semiconductor circuit breaker 12 to the mechanical interruption switch 10, the electrical voltage dropped across the varistor 32 always corresponds to the electrical voltage dropped across the mechanical interruption switch 10. The varistor 32 is intended to reduce the current taken over by the semiconductor circuit breaker 12 to zero. The hybrid circuit breaker device 30 has a further mechanical interruption switch 22. The further mechanical interruption switch 22 is arranged in series with the semiconductor circuit breaker 12. The further mechanical interruption switch 22 is arranged in series with the mechanical interruption switch 10. The further mechanical interruption switch 22 is arranged in series with the varistor 32. The further mechanical interruption switch 22 is intended to be triggered at a time offset from the mechanical interruption switch 10. The further mechanical interruption switch 22 is intended to trigger more slowly than the mechanical interruption switch 10. The further mechanical interruption switch 22 is intended to create and maintain galvanic isolation of the circuit.

The hybrid contactor 28 has a maintenance switch 38. The maintenance switch 38 is intended to allow an opening of a circuit monitored by the hybrid circuit breaker device 30. The maintenance switch 38 is intended to open the circuit without load. The maintenance switch 38 can be opened, for example, to enable maintenance of the circuit. The maintenance switch 38 can be operated manually or automatically. The maintenance switch 38 is formed separately from the hybrid circuit breaker device 30. The mechanical interruption switch 10 is designed to be completely coil-free. The hybrid circuit breaker device 30 is designed to be free of choke coils. The hybrid contactor 28 is designed to be free of choke coils.

The 2a and 2 B show a schematic representation of a part of the hybrid circuit breaker device 30, which includes the mechanical interruption switch 10 and the further mechanical interruption switch 22. The mechanical interruption switch 10 has a trigger element 14. The trigger element 14 is sensitive to magnetic fields. The trigger element 14 is arranged in a close area of a current-carrying conductor piece 40 of the circuit. The trigger element 14 is arranged parallel to the current-carrying conductor piece 40. The trigger element 14 is arranged such that the longitudinal directions of the trigger element 14 and conductor piece 40 run at least substantially parallel to one another. The trigger element 14 is intended to create an interruption in the circuit by changing its shape. The trigger element 14 is intended to create an interruption in the circuit by changing its length. The trigger element 14 is intended to actuate a switch that physically separates the circuit by changing the length and/or the shape. In the 2a and 2 B The switch is shown as an example as a toggle switch. The trigger element 14 is partially made of a magnetic shape memory alloy 16. Alternatively, the trigger element 14 can also be formed completely or almost completely from a magnetic shape memory alloy 16. The triggering element 14 is aligned and/or arranged in such a way that a magnetic field caused by a change in current flow in the conductor piece 40 is guided through the triggering element 14 in such a way that a change in shape of the magnetic shape memory alloy 16 is brought about. The magnetic shape memory alloy 16 is formed as a high-temperature magnetic shape memory alloy. In the 2a the trigger element 14 is in an undeformed state. In the 2 B the trigger element 14 is in a deformed state. In the 2 B the trigger element 14 has an elongated shape compared to the undeformed state. The 2a shows the state of the mechanical circuit breaker 10 in normal operation. The 2 B shows the state of the mechanical interruption switch 10 in the event of a fault.

The 2a shows the state of the further mechanical interruption switch 22 in normal operation. The further mechanical interruption switch 22 is closed. The 2 B shows the state of the further mechanical interruption switch 22 in the event of a fault. The further mechanical interruption switch 22 is open. The further mechanical interruption switch 22 has a trigger element 26, which is at least partially formed from a magnetic shape memory alloy 16. The triggering element 14 of the mechanical interruption switch 10 also represents the triggering element 26 of the further mechanical interruption switch 22. The change in length of the triggering element 14 also triggers the opening of the further mechanical interruption switch 22. Alternatively, the further mechanical interruption switch 22 could also be opened by a further trigger element that is separate from the trigger element 14, in particular in a way that is comparable to the trigger element 14.

The hybrid circuit breaker device 30 has a delay unit 24. The delay unit 24 is intended to time-delay an effect of the triggering element 14, 26 on the further mechanical interruption switch 22 relative to an effect of the triggering element 14, 26 on the mechanical interruption switch 10. The delay unit 24 is formed, for example, by a toggle switch spaced apart from the further mechanical interruption switch 22. Alternative configurations for delay units 24 that fulfill the same task according to the invention are conceivable and can be derived by the person skilled in the art from their specialist knowledge.

The 3a and 3b show schematically a top view of the mechanical interruption switch 10. A course of the magnetic field generated by the conductor piece 40 is indicated by magnetic field lines 42. The magnetic field lines 42 pass through the trigger element 14 perpendicular to its longitudinal extent. The Indian 3a Mechanical interruption switch 10 shown is, apart from the magnetic shape memory alloy 16 of the triggering element 14, designed to be free of magnetic flux-conducting components. Alternatively, the conductor piece 40 can, however, as in the 3b shown, can also be surrounded by a magnetic flux-conducting sleeve 44, into which the trigger element 14 is inserted.

Like in the 3a and 3b shown as an example, the mechanical interruption switch 10 can comprise a thermosensitive trigger element 26 in addition to the magnetic field-sensitive trigger element 14. The thermosensitive trigger element 26 is intended to interrupt the circuit in the event of an overload. The thermosensitive triggering element 26 is intended to experience a change in length when a limit temperature is exceeded and thereby open the mechanical interruption switch 10, in particular analogous to the function of the magnet-sensitive triggering element 14. The thermosensitive triggering element 26 consists at least to a large extent, preferably completely or almost made entirely of a thermal shape memory alloy 52.

The 4 shows the magnet-sensitive trigger element 14 with a schematic internal structure. The trigger element 14 comprises a plurality of twin boundaries 18, 20. The twin boundaries 18, 20 can be activated by a (mechanical) upper surface treatment of the magnetic shape memory alloy 16 can be generated. The twin boundaries 18, 20 can be moved coherently. Distances 46 between adjacent twin boundaries 18, 20 of the trigger element 14 are smaller than 300 μm, preferably smaller than 150 μm.

The 5 shows a schematic flow diagram of a method for operating the hybrid circuit breaker device 30. In at least one method step 48, the mechanical interruption switch 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 interruption switch 10 is actuated in the event of an overload by a change in shape of the thermal shape memory alloy 52.

The 6 shows schematically time-dependent current curves 58 through components of the hybrid contactor 28. Based on 6 The basic functionality of the hybrid contactor 28 will be briefly explained below. On an abscissa 54 is in the 6 applied for a time. The times t ₁ to t ₅ are specifically marked on the abscissa 54. On an ordinate 56 are in the 6 Current intensities are plotted as they can occur on the components of the hybrid contactor 28 in the event of a fault. From top to bottom are in the 6 the following current curves 58 are shown: a) total current through the hybrid contactor 28; b) current through the mechanical circuit breaker 10; c) current through the semiconductor circuit breaker 12 and d) current through the varistor 32. At the beginning up to time t ₁ , the current intensity corresponds to a nominal value of normal operation and flows completely via the path of the mechanical interruption switch 10, which is closed in normal operation. The error occurs at time t ₁ . The fault event results in a rapid increase in the current flowing through the mechanical interrupter switch 10. The resulting magnetic field leads to a deformation of the magnetic shape memory alloy 16 of the trigger element 14 and thus to an opening of the mechanical interruption switch 10. Opening the mechanical interruption switch 10 creates an arc and an associated arc voltage. The arc voltage also occurs at the semiconductor circuit breaker 12. Once a minimum voltage at the semiconductor circuit breaker 12 is exceeded at time t ₂ , the semiconductor circuit breaker 12 allows current to flow. The period between times t ₁ and t ₂ is called opening time 36. Up to time t ₃ , the current flow commutates completely from the mechanical interruption switch 10 to the semiconductor circuit breaker 12. After the current has completely commutated to the semiconductor circuit breaker 12, the mechanical circuit breaker 10 opens completely. At a time t ₄ the semiconductor circuit breaker 12 is closed/switched off. This happens as soon as the mechanical interrupter switch 10 is safely opened far enough. As a result, the current in the path of the semiconductor circuit breaker 12 drops almost suddenly to zero. The current commutates completely to the varistor 32. The varistor 32 leads the current to zero until time ts. After time t _5, the further mechanical interruption switch 22 opens with a time delay.

The 7 and 8th each show schematic circuit diagram representations of hybrid contactors 28 ', 28'' with additional elements for a controlled opening of the circuit under load. In the 7 an embodiment of the hybrid contactor 28' is shown, which includes an electromagnet 34. The electromagnet 34 is designed and/or arranged in such a way that a magnetic field that can be generated by the electromagnet 34 can cause an actuation of the trigger element 14 of the mechanical interruption switch 10. If the mechanical interruption switch 10 is to be opened in a controlled manner, the electromagnet 34 is activated and generates a magnetic field which produces a change in shape of the triggering element 14 comparable to the case of a short circuit. In the 8th an embodiment of the hybrid contactor 28" is shown, which comprises a capacitor 60, which is electrically connected in parallel with the mechanical interruption switch 10 and which can be discharged by means of a switch 62 of the hybrid circuit breaker device 30. The capacitor 60 is charged in normal operation. When the switch 62 is closed is, the capacitor 60 discharges suddenly and generates a high current flow, at least for a short time. The high current gradient when the capacitor 60 is discharged creates a magnetic field which is large enough to actuate the triggering element 14 of the mechanical interruption switch 10. If the mechanical If the interruption switch 10 is to be opened in a controlled manner, the switch 62 is closed and a magnetic field is generated by the discharge of the capacitor 60, which produces a change in shape of the triggering element 14 comparable to the real case of a short circuit. The electromagnet 34 of the embodiment from the 7 and the capacitor 60 of the embodiment from the 8th are each intended to allow a controlled opening of the circuit monitored by the hybrid circuit breaker device 30.

Reference symbols

10

Mechanical circuit breaker

12

Semiconductor circuit breaker

14

Trigger element

16

magnetic shape memory alloy

18

Twin border

20

Twin border

22

Another mechanical circuit breaker

24

Delay unit

26

Trigger element

28

Hybrid contactor

30

Hybrid circuit breaker device

32

Varistor

34

Electromagnet

36

Opening time

38

Maintenance switch

40

Ladder piece

42

Magnetic field line

44

cuff

46

Distance

48

Procedural step

50

Procedural step

52

Thermal shape memory alloy

54

abscissa

56

ordinate

58

Current flow

60

capacitor

62

Switch

Claims (16)

Hybrid circuit breaker device (30), in particular DC hybrid circuit breaker device, with at least one mechanical interruption switch (10) and with at least one semiconductor circuit breaker (12), in particular a semiconductor relay, connected electrically in parallel to the mechanical interruption switch (10), characterized in that the mechanical interruption switch (10) has a, in particular magnetic field-sensitive, trigger element (14), which is at least partially formed from a magnetic shape memory alloy (16). Hybrid circuit breaker device (30). Claim 1 , characterized in that the mechanical interruption switch (10) has an opening time (36) of less than 400 µs, preferably less than 200 µs, in the event of a trip. Hybrid circuit breaker device (30). Claim 1 or 2 , characterized in that the trigger element (14), in particular produced by a (mechanical) surface treatment of the magnetic shape memory alloy (16), comprises a plurality of coherently movable twin boundaries (18, 20). Hybrid circuit breaker device (30). Claim 3 , characterized in that distances (46) between adjacent twin boundaries (18, 20) of the trigger element (14) are smaller than 300 µm, preferably smaller than 150 µm. Hybrid circuit breaker device (30) according to one of the preceding claims, characterized in that the mechanical interruption switch (10) is designed to be coil-free. Hybrid circuit breaker device (30) according to one of the preceding claims, characterized by a design free of a choke coil. Hybrid circuit breaker device (30) according to one of the preceding claims, characterized in that the mechanical interruption switch (10), apart from the magnetic shape memory alloy (16) of the triggering element (14), is at least substantially free of magnetic flux-conducting components. Hybrid circuit breaker device (30) according to one of the preceding claims, characterized by at least one further mechanical interruption switch (22) arranged in series at least with the semiconductor circuit breaker (12), which is intended to trigger with a time delay and/or slower to the mechanical interruption switch (10). . Hybrid circuit breaker device (30). Claim 8 , characterized in that the further mechanical interruption switch (22) has a trigger element (26), which is at least partially formed from a magnetic shape memory alloy (16). Hybrid circuit breaker device (30). Claim 9 , characterized in that the triggering element (14) of the mechanical interruption switch (10) also represents the triggering element (26) of the further mechanical interruption switch (22). Hybrid circuit breaker device (30). Claim 10 , characterized by a delay unit (24), which is intended to have an effect of the trigger element (14, 26) on the white to delay the lower mechanical interruption switch (22) relative to an effect of the trigger element (14, 26) on the mechanical interruption switch (10). Hybrid circuit breaker device (30) according to one of the preceding claims, characterized in that the magnetic shape memory alloy (16) is designed as a magnetic high-temperature shape memory alloy. Hybrid circuit breaker device (30) according to one of the preceding claims, characterized in that the mechanical interruption switch (10), in particular in addition to the magnetic field-sensitive triggering element (14), comprises a thermosensitive triggering element (26). Hybrid contactor (28), in particular DC hybrid contactor, with the hybrid circuit breaker device (30) according to one of the preceding claims, and with at least one varistor (32) electrically connected in parallel to the hybrid circuit breaker device (30). Hybrid contactor (28). Claim 14 , characterized by an electromagnet (34) and / or by a capacitor (60) electrically connected in parallel to the mechanical interruption switch (10) and dischargeable by means of a switch (62), each of which is at least intended to ensure a controlled opening of the hybrid circuit breaker device (30) monitored circuit. Method for operating a hybrid circuit breaker device (30), in particular a DC hybrid circuit breaker device, preferably according to one of Claims 1 until 13 , with at least one mechanical interruption switch (10) and with at least one semiconductor protective switch (12) connected electrically in parallel to the mechanical interruption switch (10), in particular a semiconductor relay, characterized in that the mechanical interruption switch (10) in the event of an overcurrent by a Change in shape of a magnetic shape memory alloy (16) is actuated.

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