CN107819319B - Device for collecting and breaking fault current - Google Patents

Abstract

The invention relates to a device for collecting and disconnecting fault currents. A first switch contact is arranged in a first wire between a first input terminal on the grid side and a first output terminal on the consumer side, and a first switch contact is arranged in a first wire. In the two conductors, a second switch contact is arranged between the second input terminal on the grid side and the second output terminal on the consumer side, the first and second switch contacts are connected to a magnetic release, the magnetic release has a magnetic yoke, the yoke has first and second legs, the first leg has a first field winding and the second leg has a second field winding, the field windings are coordinated with each other so that the field windings in the yoke in fault-free current operation produce The magnetic fluxes cancel each other out. The legs have sensor windings that can be used to determine the magnetic flux difference, which are connected to a control unit configured to output a trigger current to the sensor winding when the magnetic flux difference exceeds a first threshold value, so that a magnetic flux is generated in the magnetic release , which triggers the magnetic release to open the switch contacts.

Description

Device for collecting and breaking fault current

technical field

The present invention relates to a device configured for capturing and breaking fault currents and to a fault current protection switch having such a device.

Background technique

Conventional fault current circuit breakers, which are designed to detect and disconnect fault currents, use the transformer principle for this purpose, but they cannot be used for direct fault currents. The AC-sensitive fault current circuit breaker has a summing current transformer, via which a first line leading to the consumer and a corresponding second line returning from the consumer. A fault current is referred to in this context if the current flows to ground on the consumer side. This fault current can now be detected by means of a summing current transformer, since the sum of the outgoing and returning currents detected in absolute value in the case of a fault current does not equal zero. The trigger mechanism is actuated by the relay, which interrupts the lead and optionally the return. A fault current protective switch for capturing alternating fault currents is generally known from publication DE 44 32 643 A1.

Patent application DE 10 2010 034 001 A1 discloses a device for capturing and breaking DC fault currents. It has a first switching contact, which is arranged in the transmission line between a first input terminal on the grid side and a first output terminal on the consumer side. Furthermore, the device has a second switching contact which is arranged in the return line between the second input terminal on the grid side and the second output terminal on the consumer side. The first and second switch contacts are here operatively connected to a magnetic release having a yoke with two legs, each of which is associated with an excitation winding that is tuned to each other so that in the absence of During the operation of the fault current, the magnetic fluxes generated by the field windings in the yoke cancel each other out. Furthermore, a first measuring resistor is connected in the transmission line and a second measuring resistor is connected in the return line. The first field winding is connected to the connection of the first measuring resistor and the second field winding is connected to the connection of the second measuring resistor, so that a magnetic flux is induced in the yoke in the event of a DC fault current on the consumer side No longer cancel each other out, thereby opening at least one of the two switch contacts by triggering the magnetic release.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a DC and AC sensitive fault current protection switch, which is characterized by good operation safety.

The above-mentioned technical problem is solved by the device according to the invention for collecting and disconnecting a fault current and by the fault current protection switch according to the invention.

According to the invention, a first switching contact is arranged in the first line between the first input terminal on the grid side and the first output terminal on the consumer side. A second switching contact is arranged in the second line between the second input terminal on the grid side and the second output terminal on the consumer side. The first and second switch contacts are operatively connected to a magnetic release having a magnetic yoke. The yoke can have, for example, a first leg and a second leg. The magnetic yoke has first and second field windings, which are coordinated with each other so that the magnetic fluxes generated by the field windings in the magnetic yoke cancel each other out in fault-free operation. The first field winding conducts at least one sub-current of the first conductor, and the second field winding conducts at least one sub-current of the second conductor. At least one sub-current means a portion of the current that can conduct the wire, as well as all the current in the wire. That is, the entire current of eg a wire conducts through the field winding. Field winding also refers to a winding that has only one or half turns. That is, for example, only one conductor can be guided through the magnetic release or the yoke or the magnetic flux circuit. The yoke has a sensor winding which is connected to the control unit. The control unit is designed to be able to determine the magnetic flux difference. In the event that the magnetic flux difference exceeds the first threshold, a triggering current is output to the sensor winding such that a magnetic flux is generated in the magnetic release which causes the magnetic release to trigger, thereby opening the at least one switch contact.

The device for capturing and disconnecting fault currents constructed in this way has the advantage that it can be used for direct current as well as alternating current. Furthermore, only one magnetic circuit is used for the functions of the holding magnetic circuit and the summing current transformer. Furthermore, this solution is characterized by a high robustness, since the current difference or the magnetic flux difference is not used directly for triggering, ie for interrupting the circuit of the first and second conductors. Instead, the magnetic flux difference is collected electronically, possibly further processed electronically, and compared to a threshold or duration threshold, i.e. the threshold must exist for a certain duration and when it is exceeded or a predefined trigger criterion is met prompt trigger. It is implemented according to the invention so that the magnetic circuit is used for acquisition and also for triggering or disconnecting. This can be achieved by the fact that the sensor winding is also used as a release winding at the same time, wherein a current is applied to the sensor winding, which generates a magnetic flux in the magnetic release, which triggers the magnetic release and opens the at least one switch contact point. As a result, short-term magnetic flux differences do not necessarily lead to triggering, but only after an electronic analysis has been performed and predetermined criteria have been met. As a result, a compact structure and robust functionality can be achieved. Due to this structural design, the simply constructed device is also characterized by high availability, which also contributes to a high operational safety of the device.

In the case of DC applications or full current sensitive applications, care must be taken that the first field winding and the second field winding are connected in the correct polarity.

Preferred implementations are the subject of the present invention.

In a preferred implementation of the invention, the yoke has a release winding. The trigger current is delivered to the release winding, not the sensor winding. In this way, a magnetic flux is generated in the magnetic release, which causes the magnetic release to trigger, thereby opening the at least one switch contact. This has the advantage in particular that even the triggering process can be monitored by the sensor winding. This makes it possible, for example, to check whether the release winding is functioning properly and that sufficient magnetic flux is generated for the magnetic release to open the switching contacts.

In a preferred implementation of the invention, the first measuring resistor is connected in the first line and the second measuring resistor (24) is connected in the second line (20). The first field winding is connected to the junction of the first measurement resistor, and the second field winding is connected to the junction of the second measurement resistor. This has the advantage in particular that it provides a solution for conducting the sub-current via the excitation coil. In this way, a small device for capturing and disconnecting fault currents can also be realized in the event of large currents in the circuit, ie in the first and second lines.

In a preferred implementation of the invention, the first switch contact and/or the second switch contact can be operated by a switch mechanism, and the triggering of the switch mechanism can be initiated by a magnetic release. This has the advantage in particular that, with the device, even smaller magnetic fluxes reliably lead to triggering. Thereby, a magnetic release with relatively small forces can be achieved. By means of the switching mechanism, which is arranged between the magnetic release and the switching contacts and is operatively connected to the magnetic release and the switching contacts, the relatively small forces of the magnetic release are reduced by the energy storage (stored energy) present in the switching mechanism. spring), which can be transmitted in a magnified manner, enabling a fast and reliable triggering of the switch contacts.

In a preferred implementation of the invention, the magnetic flux induced in the yoke can be determined by measuring the magnitude of the resistance and/or can be adjusted by the geometrical design of the excitation coil. This has the advantage in particular that the working capacity of the device can be adjusted by sizing or design. The magnetic fluxes induced in the yoke should cancel each other in the absence of fault currents. This can be achieved in various ways, for example by sizing the measuring resistance accordingly, but also by the geometrical design of the field coil, for example by the number of turns; the polarity can be changed by the winding direction.

In a preferred implementation of the invention, the magnetic release has permanent magnets. This has the advantage in particular that the combination of a magnetic circuit or a magnetic release can be achieved by means of a constant magnetic flux, which is especially advantageous for DC applications. Thus, for example, the armature can be held.

In a preferred implementation of the invention, the magnetic release has an armature through which the magnetic flux of the yoke flows. This has the advantage in particular that the armature can be used as the release element of the magnetic release, for example when, in particular in the case of direct current, the magnetic flux difference is so large that it should directly cause the switching contacts to trigger or open. It may be the release element of a magnetic release when triggered by a trigger current.

In a preferred implementation of the invention, the armature is connected to at least one spring. This has the advantage in particular that it is possible to realize a magnetic release with an armature without permanent magnets, wherein the armature is pressed against the yoke by a spring.

In a preferred implementation of the invention, the yoke has a further field winding for conducting at least the partial currents of the three-phase alternating current circuit, so that the fault current can be detected and disconnected. This has the advantage in particular that the solution according to the invention can also be used in a three-phase alternating current network. In the case of a yoke with several legs, it is also possible to arrange all field windings on one leg. The yoke can also be constructed as a single-leg yoke.

In a preferred implementation of the invention, the control unit is designed with a filter and an analog-to-digital converter, with which the signals of the sensor windings are processed, and a microprocessor with a memory, which checks whether the processed sensor signal exceeds the first a threshold value and, when exceeded, causes current to flow through the sensor winding or release winding. This has the advantage, in particular, that an electronic or digital processing of the sensor signals is possible, whereby, for example, a plurality of evaluations, acquisitions and functions can be carried out with the aid of a microprocessor.

Preferably, the device can be used in a fault current protection switch, with which the aforementioned advantages can be achieved. In particular, a fault current protective switch for direct current and/or alternating current can be realized, whereby all current-sensitive protective elements are provided.

All implementations, in a relevant manner and only in relation to individual features or in combination of features, lead to improved detection and disconnection of fault currents.

Description of drawings

The described characteristics, characteristics and advantages of the invention and the manner of realization thereof will become clearer and easier to understand with the help of the following description of the embodiments explained in detail in conjunction with the accompanying drawings.

In the attached picture:

1A and 1B show schematic diagrams of the measuring principle of the device for collecting and breaking fault current according to the present invention;

Figure 2 shows a schematic diagram of a first device;

Figure 3 shows a schematic diagram of the second device;

Figure 4 shows a schematic diagram of a third device;

Figure 5 shows a schematic diagram of a fourth device;

Figure 6 shows a schematic diagram of a fifth device;

Figure 7 shows a schematic diagram of a sixth device.

Identical parts always have the same reference numerals in the different representations of the drawings. The description applies to all figures of the drawings in which corresponding parts are also seen.

Detailed ways

FIGS. 1A and 1B schematically show the measuring principle of the device according to the invention for collecting and breaking fault currents. FIG. 1A here shows a strongly simplified circuit diagram of the device in trouble-free operation. To determine the fault current, the current or voltage difference principle is used here: the device has a first input terminal 11 and a second input terminal 21 on the input side, which are designed for connecting the device to the power supply network 60 . On the output side, the device has a first output terminal 12 and a second output terminal 22 , which are designed for connecting a consumer 50 . The first measurement resistor 14 is electrically connected between the first input terminal 11 and the first output terminal 12 , and the second measurement resistor 24 is electrically connected between the second input terminal 21 and the second output terminal 22 . In fault-free operation, ie as long as no fault current occurs, a current I flows from the supply network 60 (not shown in FIG. 1 ) via the first input terminal 11 , which can be measured at the first measuring resistor 14 as I ₁ ,, measured as IV at the consumer ₅₀ and as I ₂ at the second measuring resistor. That is, in a trouble-free operating state:

I ₁ =I _V =I ₂

If the first measuring resistor 14 now has an ohmic resistance value R ₁ , which is the same size as the ohmic resistance value R ₂ of the second measuring resistor 24 , the following relationship holds:

R ₁ =R ₂ ,

Then, according to Ohm's law, the voltage U ₁ applied to the first measuring resistor 14 corresponds to the voltage U ₂ applied to the second measuring resistor 24 . This establishes:

This is characteristic of the trouble-free operation of the device. In this state, no fault current _IF flows to ground on the consumer side.

FIG. 1B shows the faulty operating state of the device, in which on the consumer side 50 the fault current _IF flows to ground. Here, the basic structure of the device corresponds to the structure described in FIG. 1A . In contrast to this, the _equation I ₁ =IV =I ₂ that applies to fault-free operation no longer applies in this case. Instead it now holds:

I ₁ =I ₂ + _IF

In this case, the potential of the second input terminal 21 is grounded, for example, on the side of the power supply network.

Since the relationship R ₁ =R ₂ also always holds for the two measuring resistors 14 and 24 , but at the same time I ₁ >I ₂ in the case of a fault current (see above), it follows that the first measuring resistor 14 is applied to the The voltage U ₁ across must be greater than the voltage U ₂ applied to the second measuring resistor 24 . The following relationship is established:

U ₁ >U ₂ or ΔU=U ₁ -U ₂ ,

It is caused by the outgoing fault current _IF . The resulting voltage difference ΔU or current difference between the first measuring resistor 14 and the second measuring resistor 24 can thus be used to trigger the device.

FIG. 2 shows in a schematic diagram the working principle of monitoring and triggering in the device. The input terminals 11 and 21 are in turn provided for connecting the device to the power supply network; the output terminals 12 and 22 are used for connecting electrical consumers. A first measuring resistor 14 and a first switching contact 13 connected in series are arranged in the first line 10 between the first input terminal 11 and the first output terminal 12 ; in the second line 20 between the second input terminal 21 and A second measuring resistor 24 and a second switching contact 23 connected in series are correspondingly arranged between the second output terminals 22 . The first switching contact 13 and the second switching contact 23 are operatively connected to the switching mechanism 3 of the device, which is provided for opening the switching contacts 13 and 23 in the event of a fault current.

For monitoring and triggering, the device has a magnetic release 5 which is mechanically connected to the first switch contact 13 and to the second switch contact 23 via the switch mechanism 3 . The magnetic release 5 is connected to the switching mechanism 3 via an operative connection, eg via a release lever (not shown), and has an armature 2 , a permanent magnet 4 and a yoke with a first leg 6 and a second leg 7 . The yoke is in this case constructed in two parts with separate feet 6 and 7 . However, it can also be implemented in one piece. The yoke can also have only one leg. Any configuration is contemplated here as long as a closed magnetic circuit or flux can be achieved.

In the de-energized state, a magnetic flux Φ occurs in the yoke due to the permanent magnets 4 , which is large enough to keep the armature 2 at the ends of the two legs 6 and 7 against the opposing force of the spring 31 .

In order to detect the voltage difference ΔU or the current difference from which the fault current can be deduced, a first field winding 8 is arranged on the first leg 6 , which is connected to the connection of the first measuring resistor 14 . A second field winding 9 is arranged on the second leg 7 , which is connected to the connection of the second measuring resistor 24 . As a result of the voltage U ₁ applied to the first measuring resistor 14 or by the current flowing through the first field winding 8, a magnetic flux Φ ₁ is generated in the first leg 6 of the yoke; the same applied to the second measuring resistor 24 The voltage U ₂ or the current flowing through the second field winding 9 generates a magnetic flux Φ ₂ in the second leg 7 of the yoke. Here, for the DC case (or for all current-sensitive cases), the field windings 8 and 9 are electrically connected to the corresponding measuring resistors 14 or 24 or polarized so that the two induced fluxes Φ ₁ and Φ ₂ are in the magnetic Roads are oriented opposite to each other. Thus, in fault-free operation, the magnetic fluxes Φ ₁ and Φ ₂ generated in the yoke due to the relationship U ₁ =U ₂ of the voltages U ₁ and U ₂ cancel each other out, so that the armature 2 continues to remain at the two legs 6 and 7 end of .

In the case of a fault current _IF , the current flows to ground on the consumer side, so that the current I ₂ flowing back via the return line 20 is smaller than the current I ₁ conveyed via the transmission line 10 . Established:

I ₁ >I ₂

Since the ohmic resistance values R1 and R2 of the two measuring resistors 14 and 24 are of the same magnitude, it follows that the voltage U ₂ is correspondingly reduced relative to U ₁ in the presence of a fault current _IF . So the following relationship holds:

U ₁ >U ₂

If a lower voltage U ₂ is applied to the second measuring resistor 24 , it follows that a lower magnetic flux Φ ₂ is also induced by the second field winding 9 . So in case of fault current it holds:

Φ ₁ >Φ ₂

If the magnetic flux Φ ₁ generated by the first field winding 8 is greater than the magnetic flux Φ ₂ induced by the second field winding 9 , the magnetic flux Φ is weakened, and the magnetic path of the magnetic release 5 is thus unbalanced.

This change in the magnetic flux or the magnetic flux difference with respect to the magnetic flux of the permanent magnet for the DC case or the magnetic flux difference for the AC case is now detected by the sensor winding 41 . The sensor winding 41 is connected to a control unit 61 not shown in FIG. 2 . The control unit compares the determined magnetic flux difference with a first threshold value and, when exceeded, outputs a trigger current to the sensor winding 41, resulting in a large third magnetic flux or reduction in the magnetic flux Φ, which is sufficiently large , so that the magnetic release is triggered, thereby opening at least one switch contact. For example, a third magnetic flux is generated or the magnetic flux Φ is weakened, so that the magnetic holding force is no longer sufficient to hold the armature 2 against the force of the spring 31 . The deflection of the armature 2 causes the switching mechanism 3 to thus be triggered, thereby opening the switching contacts 13 and 23 .

In the case of alternating currents, the magnetic flux difference can be determined directly from the current induced in the sensor winding 41 , for example. In the case of a direct current, the change in the magnetic flux or the difference in magnetic flux can be determined by an alternating current flowing in the sensor winding or sensor coil 41 and applied by the control unit 61 , eg by an oscillator. By means of the filter in the control unit 61, the magnetic flux difference can be determined for the DC case as well as for the AC case, so that a device suitable for all currents can be realized.

FIG. 3 shows the device according to FIG. 2 with the difference that the first and second measuring resistors 14 , 24 are not provided, but instead the first and second conductors 10 , 20 are guided through the magnetic release 5 , more precisely by means of a yoke having two legs 6 , 7 , for example, the field winding is formed directly. The two conductors thus directly form the field windings 8 , 9 . In the case according to FIG. 3 , the field windings each have a half-turn electrically.

Furthermore, the magnetic release 5 has a release winding 42 . The release winding is arranged on the yoke, for example on the first leg 6 . It is likewise connected to a control unit 61 not shown in FIG. 3 . In this example, the trigger current of the control unit 61 is not transmitted to the sensor winding 41 but to the release winding 42 . The resulting reduction of the magnetic flux or flux Φ, for example, by raising the armature 2 , ie by breaking the magnetic circuit of the magnetic release 5 , causes the magnetic release to be triggered. The contacts 13 , 23 can be opened by the switching mechanism 3 .

FIG. 4 shows the device according to FIG. 2 with the difference that the magnetic release 5 here also has a release winding 42 . In this example on the yoke, in particular on the first leg 6 .

The field winding, sensor winding and possibly release winding can be located anywhere in the magnetic release. The illustration with the first and second legs has been chosen only by way of example. Furthermore, in the case of a DC voltage, only the direction of the winding or the magnetic flux is critical, which can be predetermined by the polarity of the DC voltage or, if necessary, changed or adjusted on the winding by changing the polarity of the connections.

FIG. 5 shows the device according to FIG. 2 with the difference that the magnetic release 5 has a one-piece magnetic yoke. In addition, the permanent magnet 4 is not provided. Instead of the permanent magnet 4 attracting the armature 2 by its magnetic flux Φ, a second or second and third springs 32, 33 are provided. These springs press the armature 2 against the yoke of the magnetic release 5 .

If a trigger current is output to the sensor winding 41 , the armature 2 is pushed open by the magnetic flux, thereby triggering the magnetic release, whereby the switching contacts 13 , 23 are opened, for example by the switching mechanism 3 .

Furthermore, in FIG. 5, a release coil 42 may also be arranged on the yoke. The field coils 8 , 9 can be arranged on any section of the yoke, as already explained.

FIG. 6 shows a schematic arrangement with a supply network 60 and a consumer 50 between which the arrangement according to the invention is arranged. The magnetic release 5 with the lines 10 , 20 is here incorporated into the summing current unit 63 . It is operatively connected to the contacts 13 , 23 . According to the invention, the summing current unit 63 has a sensor winding 41 and a release winding 42 . The sensor winding 41 is connected to the control unit 61 . The release winding 42 is likewise connected to the control unit 61 . A further exemplary connection of the release winding 42 to the resistor R, the thyristor and the capacitor is shown in FIG. 6 . The gate connections of the thyristors are here connected to the control unit 61 .

The control unit 61 is in turn connected to a power supply 62 for power supply, which in turn is connected to the first and second lines 10 , 20 on the supply grid side 60 .

FIG. 7 shows the arrangement according to FIG. 6, with the difference that the release winding 42 is connected to the power supply 62, for example by means of transistors, thyristors, triacs or other switching elements, the control connections of which are again Connected to the control unit 61 . This makes it possible to transmit the trigger current to the release winding 42 in the event of a fault.

The control unit 61 has further components such as an amplifier 71, a filter 72 (eg a low-pass filter, a high-pass filter, a band-pass filter or a band-stop filter), an analog-to-digital converter 73, a microprocessor 74 and/or memory 75.

The magnetic release 5, in particular the yoke, preferably consists of a ferromagnetic material.

The invention is explained again in another language below.

According to the invention, it is provided that the holding magnet or the magnetic release also acts as a summing current transformer. Especially for fault current protection switches in low voltage grids. Here, a common magnetic circuit with a ferromagnetic core is used for the functional part of the holding magnet and the summation current sensor. The present invention can be used for AC voltage as well as DC voltage applications, as in such low voltage grids.

FIG. 3 shows a two-pole arrangement with functional component (primary) conductors, switch contacts/contact systems, switch locks, holding magnets and summing current transformers, as in a fault current protective switch. Characterized by the realization of the magnetic circuit. In this magnetic circuit the (primary) wire is guided directly through the magnetic circuit. At least one sensor winding is provided. As an alternative to this, a release winding is provided.

The sensor winding is used to acquire the summed current (sinusoidal alternating current, pulsed current and/or smooth direct current) by means of an electrical trigger circuit/control unit.

The release winding provides two functions in this example: a) internal test function = "test" and b) trigger function = "trip".

The function of the release winding can also be implemented together in one winding, for example the sensor winding, that is to say integrated into one winding, for example the sensor winding.

A particular advantage of the present invention is that only one common magnetic circuit is used for at least two functions, namely the trigger/hold magnetic circuit and the summing current transformer. This saves space and costs. An additional advantage is the increased reliability of the device, since fewer components, including connecting wires, must be used. Furthermore, there is the possibility that the triggering process is monitored live by the sensor winding when the release winding is activated, thereby introducing an additional degree of safety. In this case, the sensor winding records the triggering process from the actuation until the interruption of the magnetic circuit, thereby interrupting the induction on the sensor winding to hold the magnetic circuit/lifting of the armature of the magnetic release.

The strength of the residual holding force on the armature on the holding magnet/magnetic release is designed such that overcoming (as a trigger) only occurs by activating the release winding or the energy input on the sensor winding. Triggers due to flux generation/induction purely due to the primary windings of the (primary) conductors 10, 20 are excluded.

Figure 4 shows an alternative structure. In the course of additional space savings, the primary winding can be realized by means of resistance taps. This implementation enables an extremely compact structure, but for this a significantly higher sensitivity/measurement accuracy of the sensor is required in terms of the magnetic flux or flux difference of the control unit 61 .

FIG. 5 shows a preferred embodiment with only one sensor winding or secondary winding and without permanent magnets for achieving a residual holding force on the armature. The remaining holding force is alternatively achieved by one or two springs 32 , 33 .

The solution according to the invention explained can be used as a fault current protection switch, for example as a 1+N, three-phase, 3+N and pure DC voltage/DC type.

Figure 6 shows a diagram of the electrical principle or implementation. A control unit 61 is shown, which is powered by a power supply 62 . The microprocessor 74 in the control unit 61 reads in the sum and difference current through the sensor windings and analyzes the type and magnitude of the sum (fault) current. The summing current sensor is arranged in the magnetic system holding the magnet/magnetic release. When a definable triggering threshold value is exceeded, an electronic triggering is carried out by the microprocessor 74 , eg by means of a thyristor, and the release winding 42 is energized or controlled. Subsequently, the contacts separating the consumer or load 50 from the power supply or supply source 60 are opened by controlling the release winding.

Figure 7 shows an alternate diagram of the electrical principle or implementation. The functional components of the control unit 61 can be seen therein. The trigger function is here alternatively implemented by a bipolar transistor powered by the mains.

The present invention combines the magnetic release circuit with the summing current transformer function by using a common magnetic system.

All in all, a cost-effective construction, a higher reliability with an extended service life, a saving in the number of required components and parts, a saving of space in the plant and an increase in the safety of the triggering process by monitoring are obtained.

Although the present invention is illustrated and described in detail by way of examples, the present invention is not limited to the disclosed examples, and other modifications can be derived therefrom by those skilled in the art without departing from the scope of the present invention.

List of reference signs

2 armatures

3 Switch mechanism

4 permanent magnets

5 Magnetic release with yoke

6 first leg

7 Second leg

8 The first field winding

9 Second field winding

10 First wire

11 The first input terminal

12 The first output terminal

13 First switch contact

14 First measurement resistance

20 Second wire

21 Second input terminal

22 Second output terminal

23 Second switch contact

24 Second measurement resistance

31 First spring

32 Second spring

33 Third spring

41 Sensor winding

42 Release winding

50 Consumers

60 Power grid

61 Control unit

62 Power

63 Summing current unit

71 Amplifier

72 Filters

73 Analog to Digital Converter

74 Microprocessors

75 memory

Claims (15)

1. A device for collecting and disconnecting fault current, - wherein the first line (10) is routed between the first input terminal (11) on the grid side and the first output terminal (12) on the consumer side There is a first switch contact (13), - wherein a second switch contact ( 23 ) is arranged in the second line ( 20 ) between the second input terminal ( 21 ) on the grid side and the second output terminal ( 22 ) on the consumer side, - wherein the first and second switch contacts (13, 23) are operatively connected with a magnetic release (5) having a magnetic yoke, - wherein the magnetic yoke has a first field winding (8) and a second field winding (9), which field windings are coordinated with each other such that, in fault-current operation, the first field winding (8) and the second field winding in the magnetic yoke are The magnetic fluxes (Φ1, Φ2) generated by the excitation winding (9) cancel each other out, - the first field winding (8) conducts at least one sub-current of the first conductor (10) and the second field winding (9) conducts at least one sub-current of the second conductor (20), It is characterized in that, The yoke has a sensor winding ( 41 ), which is connected to a control unit ( 61 ), which is designed to be able to determine a magnetic flux difference by means of the sensor winding ( 41 ), if the magnetic flux difference exceeds a first threshold value, A triggering current is output to the sensor winding so that a magnetic flux is generated in the magnetic release, which causes the magnetic release (5) to trigger, thereby opening the at least one switch contact (13, 23). 2. Device according to claim 1, characterised in that the yoke has a release winding (42) and a trigger current is transmitted to the release winding such that a magnetic flux is generated in the magnetic release which causes the magnetic release (5) Triggering, thereby opening at least one switch contact (13, 23). 3. The device according to claim 1, characterized in that it is constructed such that the magnetic flux difference cannot cause the magnetic release (5) to trigger. 4. The device of claim 1, wherein A first measuring resistor (14) is connected in the first wire (10), A second measuring resistor (24) is connected in the second wire (20), the first field winding (8) is connected to the junction of the first measuring resistor (14), The second field winding (9) is connected to the junction of the second measuring resistor (24). 5. Device according to claim 1, characterized in that the first switch contact (13) and/or the second switch contact (23) are operable by means of a switch mechanism (3), and the switch mechanism ( The triggering of 3) can be initiated by the magnetic release (5). 6. The device of claim 4, wherein A first measuring resistor (14) is electrically connected between the first input terminal (11) and the first switch contact (13), A second measuring resistor (24) is electrically connected between the second input terminal (21) and the second switch contact (23). 7. The device according to claim 4, characterized in that the magnetic flux (Φ1, Φ2) induced in the yoke can be determined and /or by the geometrical design of the first field winding (8) and the second field winding (9). 8. Device according to claim 1, characterized in that the magnetic release (5) has a permanent magnet (4). 9. Device according to claim 1, characterized in that the magnetic release (5) has an armature (2) through which the magnetic flux of the yoke flows. 10. Device according to claim 9, characterized in that the armature (2) is connected to at least one spring (32, 33). 11. Device according to any one of claims 1 to 10, characterized in that the yoke has a further field winding for conducting at least the partial currents of the three-phase alternating current circuit, so that the fault current can be detected and disconnected. 12. Device according to any one of claims 1 to 10, characterized in that a power supply (62) is provided, which is connected to the first line (10) and the second line (20) on the one hand and to the second line (20) on the other hand The control unit (61) is connected. 13 . The device according to claim 2 , wherein the control unit ( 61 ) is designed to have a filter ( 72 ) and an analog-to-digital converter ( 73 ), wherein the use of all the filter (72) and the analog-to-digital converter (73) process the signals of the sensor windings; and a microprocessor (74) with a memory (75) which checks the processed sensor signals Whether the first threshold is exceeded, and if so, cause current to flow through the sensor winding (41) or the release winding (42). 14. Device according to any one of claims 1 to 10, characterized in that the yoke has a first leg (6) and a second leg (7), The first leg ( 6 ) has a first field winding ( 8 ) and the second leg ( 7 ) has a second field winding ( 9 ), which are adapted to each other such that, in fault-free operation, the second field winding in the yoke is driven by the second field winding ( 9 ). The magnetic fluxes (Φ ₁ , Φ ₂ ) generated by an excitation winding (8) and a second excitation winding (9) cancel each other out. 15. A fault current protection switch having a device for collecting and breaking a fault current according to any of the preceding claims 1 to 14.

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