DE102021213119A1 - Control device for a magnetic track brake - Google Patents

Abstract

The invention relates, among other things, to a control device (34) for monitoring the function of a magnetic rail brake (10), which comprises at least one magnetic field generating device (12) for generating a magnetic field and is designed in such a way that it is activated during active braking operation on a trackside rail (20 ) rests and is raised in the inactive state and separated from the rail (20). According to the invention, the control device (34) comprises: an alternating source (341) for generating an alternating current (Iw) by the magnetic field generating device (12) or at least one AC component in a current flowing through the magnetic field generating device (12) and for generating an alternating magnetic field and an evaluation device (342) which is designed to, on the basis of measurement results which describe the AC behavior of the magnetic field generating device (12), at least one of the magnetic track brake ( 10) to form the relevant measurement information (MA).

Description

The invention relates to a control device and a method for monitoring the function of a magnetic track brake.

Magnetic rail brakes are well known in the field of railway technology. A magnetic rail brake has at least one magnetic field generating device for generating a magnetic field. In active braking mode, the magnetic rail brake rests on a trackside rail and generates a braking effect through friction; By feeding in a current through the magnetic field generating device, a magnetic attraction force can be produced between the magnetic rail brake and the rail, which increases the friction and thus the braking force. When inactive, the magnetic track brake is raised and disconnected from the track.

The invention is based on the object of specifying a control device for a magnetic rail brake, with which at least one measurement data relating to the magnetic rail brake can be formed.

According to the invention, this object is achieved by a control device having the features according to patent claim 1 . Advantageous configurations of the control device according to the invention are specified in the dependent claims.

According to the invention, it is provided that the control device comprises: an alternating source for generating an alternating current through the magnetic field generating device or at least an alternating current component in a current flowing through the magnetic field generating device and for generating an alternating magnetic field and an evaluation device which is designed for this purpose on the basis of measurement results , which describe the AC behavior of the magnetic field generating device, to form at least one measurement data relating to the magnetic track brake.

An essential advantage of the control device according to the invention can be seen in the fact that it works on the basis of measurement results that describe the AC behavior of the magnetic field generating device. The idea according to the invention is that the essential function of the magnetic track brake is based on the magnetic flux that is generated by the magnetic field generating device when current is flowing through it. The magnetic flux is in turn influenced by several factors, for example the distance between the magnetic rail brake and the rail. If the magnetic rail brake is on the rail, the magnetic flux is at its maximum due to the magnetic influence of the iron of the rail, whereas the magnetic flux is comparatively small when the magnetic rail brake is raised. Due to the change in the magnetic flux, the influence of the distance has an effect on the electrical properties, for example the inductance, of the magnetic track brake or its magnetic field generating device, which makes it possible, for example, to evaluate the AC behavior of the magnetic field generating device on the position of the magnetic track brake relative to the rail close. However, other effects can also be identified by evaluating the AC behavior of the magnetic field generating device, as will be explained in detail further below, for example wear or soiling of the magnetic track brake.

The magnetic field generating device of the magnetic track brake preferably comprises one or more coils or is formed by one or more coils.

The control device preferably comprises a voltage measuring device for measuring a voltage present at the magnetic rail brake, the magnetic field generating device or the alternating source, and a current measuring device for measuring the current flowing through the magnetic field generating device.

The evaluation device is preferably designed to form the at least one measurement information relating to the magnetic rail brake on the basis of measurement results that are supplied by the voltage measurement device and the current measurement device.

In a particularly preferred embodiment of the control device, it is provided that the evaluation device is designed such that it generates a contact signal indicating that the magnetic rail brake is in contact with the rail, depending on whether the at least one measurement data satisfies a contact condition.

The at least one measurement item or one of the measurement items in the case of two or more measurement items is preferably a phase shift-related measurement item and the seating condition is preferably a phase shift-related seating condition. In the latter case, the evaluation device is preferably designed in such a way that it calculates the phase shift between a current measured by the current measuring device and a span measured by the voltage measuring device Determines the phase measurement value indicative of voltage, the phase measurement value forming the phase shift-related measurement specification, and considers the phase shift-related seating condition to be met if the phase measurement value reaches or exceeds a predetermined phase position threshold value.

It can also advantageously be provided that the at least one measurement data or one of the measurement data in the case of two or more measurement data is a measurement data related to the absolute value of the impedance and the seating condition is a seating condition related to the absolute value of the impedance. In the latter case, the evaluation device is preferably designed in such a way that it forms an impedance vector indicating an impedance of the magnetic field generating device, with the amount of the impedance vector forming the impedance-related measurement information, and considering the impedance-related seated condition to be met if the amount of the impedance vector reaches or exceeds a predetermined impedance limit threshold value .

Provision can also advantageously be made for the at least one measurement item or one of the measurement items in the case of two or more measurement items to be a pointer angle-related measurement item and for the seated condition to be a pointer angle-related seated condition. In the latter case, the evaluation device is preferably designed in such a way that it forms an impedance vector describing an impedance of the magnetic field generating device, with the phase angle of the impedance vector forming the measurement information related to the vector angle, and considering the seated condition related to the vector angle to be fulfilled if the phase angle of the impedance vector reaches or exceeds a predetermined angle threshold value .

It can also advantageously be provided that the at least one measurement or one of the measurements in the case of two or more measurements is a quotient-related measurement and the seating condition is a quotient-related seating condition and the measurement results of the voltage measuring device and the current measuring device are effective or peak values of the current or specify the voltage. In the latter case, the evaluation device is preferably designed in such a way that it forms the quotient between the rms or peak value of the voltage and the rms or peak value of the current as the quotient-related measurement information and considers the quotient-related seating condition to be fulfilled if the last-mentioned quotient has a predetermined resistance threshold value reaches or exceeds, and/or as the quotient-related measurement data forms the quotient between the rms or peak value of the current and the rms or peak value of the voltage and considers the quotient-related seating condition as fulfilled if the latter quotient reaches or falls below a predetermined conductance threshold value.

In a preferred embodiment variant, it is provided that the evaluation device is designed in such a way that, on the basis of measurement results supplied by the voltage measuring device and the current measuring device, it forms a measured phase value indicating the phase shift between current and voltage and generates the pending signal when the measured phase value reaches or exceeds a predetermined phase shift threshold.

Alternatively or additionally, it can be provided that the evaluation device is designed in such a way that, on the basis of measurement results supplied by the voltage measuring device and the current measuring device, it forms an impedance vector describing an impedance of the magnetic field generating device and generates the presence signal when the absolute value of the impedance vector reaches or exceeds a predetermined impedance magnitude threshold value and/or the phase angle of the impedance vector reaches or exceeds a predetermined angle threshold value.

Alternatively or additionally, it can be provided that the measurement results of the voltage measuring device and the current measuring device indicate rms or peak values of the current or voltage and the evaluation device is designed in such a way that it generates the signal when a quotient forming the at least one measurement data is between the rms - or the peak value of the voltage and the rms or peak value of the current reaches or exceeds a predetermined resistance threshold value, and/or a quotient between the rms or peak value of the current and the rms or peak value of the voltage that forms the at least one measured value reaches a predetermined conductance threshold value or falls below.

Alternatively or additionally, it can be provided that the evaluation device comprises a Fourier transformation device and is designed in such a way that it subjects the time profile of current and voltage measured values of the voltage measuring device and the current measuring device to a Fourier transformation with formation of a spectrum and generates the pending signal as a function of the spectrum.

The AC source may be an AC power source or an AC voltage source or on have, which feeds an alternating current into the magnetic field generating device.

Alternatively or additionally, it can be provided that the alternating source is or has a modulation device which modulates the amplitude of the current flowing through the magnetic field generating device over time, forming the alternating current component. In the latter variant, the alternating source can therefore be a passive component that itself does not supply any current or voltage, but only modulates a current or a voltage of another component, such as a direct current source or a direct voltage source, over time in order to create an alternating magnetic flux to evoke.

The alternating current or alternating current component can be purely sinusoidal over time, i.e. only have a single frequency. Alternatively, it can be provided that the alternating current or alternating current component has two or more frequencies in the frequency spectrum.

With a view to simple signal evaluation, it is considered advantageous if the frequency or at least one of the frequencies of the alternating current or the alternating current component is in the frequency range between 10 and 40 Hz.

It is also advantageous if the evaluation device is designed in such a way that it generates a cleavage signal, which indicates that there are deposits on the magnetic rail brake at the interface to the rail, depending on whether the at least one measurement data meets a cleavage condition.

It is also advantageous if the evaluation device is designed in such a way that it generates a wear signal, which indicates the state of wear of pole shoes and end members of the magnetic rail brake, depending on whether the at least one measurement data meets a wear condition.

It is also advantageous if the evaluation device is designed in such a way that it generates a fault warning signal, which indicates that the function of the magnetic rail brake is faulty, if - although a lowering signal is present, according to which the magnetic rail brake should be on the rail - the at least one measurement information indicates the fulfillment of a predetermined fault condition. The interference condition can be regarded as fulfilled, for example, if the magnetic flux of the alternating magnetic field falls below a minimum flux value and/or there is no signal present.

It is also advantageous if the evaluation device is designed in such a way that it generates a high-level signal when the at least one measurement data or one of the measurement data satisfies a high-level condition. For example, it can generate the high-level signal if the measurement information or the measurement information does not allow the generation of the contact signal or the warning signal or the AC behavior of the magnetic field generating device indicates a magnetic flux below a minimum flux threshold and/or an inductance below a minimum inductance.

Alternatively or additionally, the measurement information and signals based thereon can be generated solely on the basis of stored comparison values that have been measured and stored in the initial state after the initial installation of the magnetic track brake or after maintenance. For example, measurement results that describe the AC behavior of the magnetic field generating device (such as the phase measurement value) can be measured and stored for the up position and the rest position (down position). By comparing the stored measurement results with current measurement results, it can be determined, for example, whether the magnetic rail brake is in the up position or the rest position, and a corresponding measurement and a corresponding signal, i.e. a rest signal or a up position signal, can be generated and output.

The other measurement data explained above and the signals described above, such as the warning signal, the cleavage signal, the maintenance signal, the wear signal and the fault warning signal, can also be formed by comparing the stored measurement results with current measurement results; the above statements apply accordingly in this regard.

The invention also relates to a method for monitoring the function of a magnetic rail brake, which comprises at least one magnetic field generating device for generating a magnetic field, the magnetic rail brake being designed in such a way that it is lowered in active, trouble-free braking operation and rests on a trackside rail and in the inactive state raised and separated from the rail.

According to the invention it is provided that a current in the form of an alternating current or at least a current with an alternating current component for generating an alternating magnetic field is fed into the magnetic field generating device and on the Based on measurement results that describe the AC behavior of the magnetic field generating device, at least one measurement data relating to the magnetic track brake is formed.

The method is preferably carried out using the control device described above.

With regard to the advantages and advantageous configurations of the method according to the invention, reference is made to the above statements in connection with the control device according to the invention and its advantageous configurations.

• 1 in einer vereinfachten Darstellung Bestandteile einer Magnetschienenbremse, die auf einer Schiene einer Eisenbahngleisanlage aufgesetzt ist und von einer Steuereinrichtung angesteuert wird, die mit einem Ausführungsbeispiel für eine erfindungsgemäße Kontrolleinrichtung ausgestattet ist,
• 2 die Steuereinrichtung gemäß 1 näher im Detail,
• 3 den zeitlichen Verlauf einer an der Magnetschienenbremse gemäß 1 anliegenden Wechselspannung und eines durch die Magnetschienenbremse gemäß 1 fließenden Wechselstromes bei der in der 1 gezeigten abgesenkten Stellung der Magnetschienenbremse, und
• 4 den zeitlichen Verlauf der Wechselspannung und des Wechselstromes im Falle, dass sich die Magnetschienenbremse in ihrer Hochlagestellung befindet und räumlich von der Schiene getrennt ist.

The invention is described in more detail below using exemplary embodiments, with examples showing:

• 1 in a simplified representation, components of a magnetic track brake that is placed on a rail of a railway track system and is controlled by a control device that is equipped with an exemplary embodiment of a control device according to the invention,
• 2 the controller according to 1 closer in detail,
• 3 according to the time course of an on the magnetic track brake 1 applied AC voltage and one by the magnetic track brake according to 1 flowing alternating current at the in the 1 shown lowered position of the magnetic track brake, and
• 4 the time course of the alternating voltage and the alternating current in the case that the magnetic rail brake is in its upper position and is spatially separated from the rail.

In the figures, the same reference numbers are used for identical components for the sake of clarity.

The 1 shows an embodiment of a magnetic rail brake 10 of a rail vehicle, not shown, which rests on a rail 20 of a trackside railway track system and can generate a braking effect through friction when the rail vehicle is moving. The magnetic rail brake 10 can with one in the 1 lifted for reasons of clarity, not shown lifting device or brought into a high position in which it is spatially separated from the rail 20; it can also be lowered onto the rail 20 with the lifting device or brought into a lower support position, as shown in FIG 1 is shown schematically as an example.

The magnetic rail brake 10 includes, among other things, a magnetic field generating device and a magnetizable core 11, the ends of which can be formed, for example, by two pole shoes 11a and 11b. The magnetic field generating device, which generates a magnetic field during active operation, can have one or more coils or be formed by one or more such coils; in the embodiment according to 1 For reasons of illustration, the magnetic field generating device comprises only a single coil 12. The structural and electrical configuration of the magnetic rail brake 10 is to be understood here only as an example; Magnetic track brakes 10 as such are generally known in railway technology, which is why a detailed description of the structural design of the magnetic track brake 10 is not required to understand the present invention.

In the representation according to 1 is the magnetic rail brake 10 in its active state, in which it rests on the rail 20 and is traversed by a direct current Ig to produce a desired braking effect. The direct current Ig flows through the coil 12, which - excited by the direct current Ig - causes a constant magnetic field and a magnetic flux Bg through the coil 12, the pole shoes 11a and 11b and the external trackside rail 20. The coil 12, the pole shoes 11a and 11b and the trackside rail 20 form the lowered state of the magnetic rail brake 10 according to FIG 1 a closed magnetic circuit.

The magnetic flux Bg in the magnetic circuit leads to a magnetic attraction between the pole shoes 11a and 11b and the trackside rail 20, whereby the magnetic rail brake 10 is pressed onto the rail 20 and the friction-related braking effect of the magnetic rail brake 10 is increased. The direct current Ig through the magnetic track brake 10 can thus also be referred to as the braking current of the magnetic track brake 10 .

In the exemplary embodiment according to FIG 1 a controller 30; an exemplary embodiment of the control device 30 according to FIG 1 is in the 2 shown, to which reference is made below.

The activation and deactivation of the active braking operation of the magnetic track brake 10, ie the switching on and off of the direct current Ig can for example, by a switch 31 and an activation device 32 of a control device 30 that controls the switch 31 . Activation device 32 can be connected to and controlled by a vehicle-side control unit, not shown in the figures, in particular a vehicle-side brake control unit, or can be integrated into such as a component, for example in the form of a software module.

To generate the direct current Ig, a direct current or direct voltage source 33 may be present, which - as in FIG 2 shown by way of example - can form part of the control device 30 . Alternatively, the direct current Ig can be provided by an external direct current network.

The controller 30 according to 1 is additionally equipped with a control device 34, which according to a magnetic alternating flux Bw in the magnetic track brake 10 and thus in the magnetic circuit 1 causes. For this purpose, the control device 34 has an electrical alternating source 341, which is an electrical alternating voltage source 341, as in FIG 2 shown, or an AC electrical source may act. The electrical AC voltage source 341 feeds in the embodiment according to FIG 1 and 2 an alternating current Iw into the coil 12. It is assumed below, for example, that the AC voltage source 341 generates alternating current or AC voltage with a single frequency, which is preferably in the range between 10 and 40 Hz.

The control device 34 also includes an evaluation device 342, the task of which is to generate one or more measurement data MA that directly or indirectly describe the state of the magnetic track brake 10 or its position. The measurement data MA or at least one of them is preferably dependent on the alternating magnetic field that is produced by the alternating voltage source 341 . Evaluation device 342 can be connected to a vehicle-side control unit (not shown in the figures), in particular a vehicle-side brake control unit, or can be integrated into such as a component, for example in the form of a software module.

In the embodiment according to 2 the evaluation device 342 is connected to a voltage measuring device 343, which measures the AC voltage Uw at the AC voltage source 341 while forming measured voltage values Uwm. Alternatively, the voltage measuring device 343 can also be connected in parallel to the coil 12 and measure the coil voltage Us at the coil 12; the alternating component of the coil voltage Us corresponds to the alternating voltage Uw at the alternating voltage source 341.

In the exemplary embodiment according to FIG 2 also in connection with a current measuring device 344, which measures the current Ig+Iw flowing through the magnetic track brake 10 or its coil 12, forming current measured values Im.

$$\left|\text{Z}\right|=\surd \left({\text{R}}^2+{\left(2\mathrm{\pi }\text{f L }\right)}^2\right)$$

wobei f die Frequenz der Wechselspannungsquelle 341 und Z die komplexe Impedanz bzw. den komplexen Impedanzzeiger der Magnetschienenbremse 10 bzw. deren Spule 12 (bezogen auf die Frequenz der Wechselspannungsquelle 341) bezeichnet.It is assumed below, for example, that the magnetic rail brake 10 according to FIG 1 between their electrical connections A1 and A2 can be described electrically at least approximately by a series connection of an ohmic resistor R and an inductance L, with the inductance L depending on the distance between the magnetic rail brake 10 and the rail 20 . With this assumption, the following applies approximately: $$\text{Z}=\text{R}+\text{j 2}\mathrm{\pi }\text{f L}$$

$$\left|\text{Z}\right|=\surd \left({\text{R}}^2+{\left(2\mathrm{\pi }\text{f L}\right)}^2\right)$$

where f denotes the frequency of the AC voltage source 341 and Z denotes the complex impedance or the complex impedance indicator of the magnetic track brake 10 or its coil 12 (relative to the frequency of the AC voltage source 341).

In the case of a large distance between the magnetic rail brake 10 and the rail 20, i.e. when the magnetic rail brake 10 is in the upper position, the inductance L is minimal due to the missing or only very small influence of the iron of the rail 20, so that the amount IZI of the impedance and the phase shift between the alternating current Iw and the alternating voltage Uw becomes minimal.

However, if the magnetic rail brake 10 is lowered onto the rail 20, as in FIG 1 shown, the inductance L becomes maximum due to the direct influence of the iron of the rail 20, so that the amount |Z| of the impedance and the phase shift between the alternating current Iw and the alternating voltage Uw become maximum.

The 3 shows in a simplified schematic representation the time profile of the AC voltage Uw and the time profile of the alternating current Iw over time t in the case that the magnetic track brake is seated directly on the rail 20, as in FIG 1 is shown, and the rail 20 with the magnetic rail brake a closed magnetic circuit forms. It can be seen that the alternating current Iw and the alternating voltage Uw are clearly phase-shifted; a phase measurement value describing the phase position or the phase shift is identified by the reference symbol V.

The 4 For comparison, FIG. 1 shows, by way of example, the time profile of the AC voltage Uw and the time profile of the alternating current Iw over time t in the case where the magnetic rail brake is separated from the rail 20. For this reason, the alternating current Iw and the alternating voltage Uw are less than in 3 out of phase; the measured phase value V is therefore smaller than in FIG 3 . In addition, the effective value Ieff of the alternating current Iw or its peak value Imax is greater than when the magnetic track brake 10 is fitted or greater than in FIG 3 , since the absolute value of the impedance IZI is also smaller because of the smaller inductance L; it is therefore valid: $$\begin{array}{l}\text{Ieff}\left(\text{elevated position}\right)>\text{Ieff}\left(\text{support position}\right)\\ \text{Imax}\left(\text{elevated position}\right)>\text{Imax}\left(\text{support position}\right)\end{array}$$

The direction of the changes is to be understood as an example. Due to different resonance and measurement frequencies or in the case of more complex electrical conditions, it can happen that the changes between active and inactive operation of the magnetic rail brake or changes in the position of the magnetic rail brake lead to an opposite direction of change.

On the basis of the time profile of the AC voltage Uw and the time profile of the alternating current Iw, the evaluation device 342 can generate one or more measurement data MA relating to the magnetic track brake. On this basis, it can also generate various signals, for example a contact signal Sa, which indicates that the magnetic track brake 10 is contacting the rail 20 in the contact position, an interference signal Sst, which indicates a fault, a skewing signal, which indicates a skewing on the magnetic track brake 10 , and/or a wear signal indicative of the wear condition of the pole pieces 11a and 11b; this is explained below using examples:

The measured phase value V as such can form one of the measurement data MA, for example, and the evaluation device 342 can generate a contact signal Sa, for example, which indicates the contact position of the magnetic rail brake 10 or its contact with the rail 20 when the measured phase value V reaches or exceeds a predetermined phase shift threshold value Vsoll , so the following applies: $$\text{V}\ge \text{vs}$$

The phase shift threshold Vsoll is preferably of the order of 5° and can be 5°, for example.

Also, the phase shift threshold value can be determined depending on a high position reference phase value Vref, which has been measured and stored in the high position of the magnetic rail brake 10; For example, the evaluation device 342 can always select the phase shift threshold value Vsoll by a predetermined differential phase value Vdiff of, for example, 3° greater than the high-level reference phase value Vref, for example according to: $$\text{vs}=\text{Vref}+\text{vdiff}$$

wobei K einen Toleranzwert zwischen 0 und 1 bezeichnet, der beispielsweise zwischen 0,1 und 0,3 liegt, so erzeugt die Auswerteinrichtung 342 vorzugsweise ein Warnsignal W, das anzeigt, dass die Magnetschienenbremse 10 auf der Schiene 20 aufliegt oder aufzuliegen scheint, der magnetische Fluss jedoch nicht ausreichend groß ist. Dieser Fall kann beispielsweise auftreten, wenn die Magnetschienenbremse stark verschmutzt oder beschädigt ist.If the measured phase value V does not reach the specified phase shift threshold value Vsoll, but just barely, if, for example, the following applies: $$\text{vs}\ge \text{V}\ge \left(1-\text{K}\right)*\text{vs}\text{,}$$

where K designates a tolerance value between 0 and 1, which is between 0.1 and 0.3, for example, evaluation device 342 preferably generates a warning signal W, which indicates that magnetic rail brake 10 is resting or appears to be resting on rail 20, the magnetic flow is not large enough. This can occur, for example, if the magnetic track brake is heavily soiled or damaged.

Instead of the current measured phase value V, the phase difference dV between the current measured phase value V and the high reference phase value Vref, which was measured and stored in the high position of the magnetic track brake 10, can be used to form the contact signal Sa; For example, the evaluation device 342 can generate the signal Sa when the phase change dV reaches or exceeds a predefined change threshold value dVsoll, i.e. the following applies: $$\text{dV}=\text{V}-\text{Vref}\ge \text{dVset}$$

The change threshold value dVsoll is preferably 3° or more.

so wird beispielsweise das Warnsignal W erzeugt.If the phase change dV does not reach the specified change threshold value, but only just not, e.g. if the following applies: $$\text{dVset}\ge \text{dV}\ge \left(1-\text{K}\right)*\text{dVset}\text{,}$$

for example, the warning signal W is generated.

Alternatively or additionally, the impedance Z can form one of the measurement data MA and the evaluation device 342 can generate the signal Sa when the absolute value |Z| of the impedance Z reaches or exceeds a predetermined impedance absolute value threshold value SW1, i.e. the following applies: $$\left|\text{Z}\right|\ge \text{SW1}$$

wird vorzugsweise das Warnsignal W erzeugt.If the amount reaches |Z| of the impedance Z does not, but only just not, the specified impedance absolute threshold value SW1 if, for example, the following applies: $$\text{SW1}\ge \left|\text{Z}\right|\ge \text{SW1*}\left(1-\text{K}\right),$$

the warning signal W is preferably generated.

Alternatively or additionally, the evaluation device 342 can generate the signal Sa when the phase angle arg(Z) of the impedance Z reaches or exceeds a predetermined angle threshold value, i.e. the following applies: $$\text{bad}\left(\text{Z}\right)\ge \text{SW}2$$

The phase angle arg(Z) of the impedance Z corresponds—apart from any conversion or detection deviations—to the phase measurement value V above, so that the angle threshold value can correspond to the phase shift threshold value Vsoll.

If the phase angle arg(Z) does not reach the angle threshold value SW2, but just barely, the warning signal W is preferably generated if, for example, the following applies: $$\text{SW}2\ge \text{bad}\left(\text{Z}\right)\ge \text{SW}2\ast \left(1-\text{K}\right).$$

Alternatively or additionally, the peak values Umax and Imax or quotients formed from them can form measurement data MA and the evaluation device 342 can generate the presence signal Sa, for example, if the quotient between the peak value Umax of the AC voltage and the peak value Imax of the current reaches or exceeds a predetermined resistance threshold value SW3. if for example: $$\text{max}/\text{Imax}\ge \text{SW}3$$

If the quotient does not reach the resistance threshold value SW3, but just barely, the warning signal W is preferably generated if, for example, the following applies: $$\text{SW}3\ge \text{max}/\text{Imax}\ge \text{SW}3\ast \left(1-\text{K}\right).$$

Alternatively, the quotient between the peak value Imax of the alternating current and the peak value Umax of the voltage can be formed and compared with a predetermined conductance threshold value in order to generate the presence signal Sa or the warning signal W.

Alternatively or additionally, the rms values or quotients formed from them can form measurement data MA and the evaluation device 342 can generate the signal Sa when the quotient between the rms value Ueff of the voltage and the rms value of the current reaches or exceeds the specified resistance threshold value SW3, i.e. when the following applies, for example: $$\text{Ueff}/\text{Ieff}\ge \text{SW}3$$

If the quotient does not reach the resistance threshold value SW3, but just barely, the warning signal W is preferably generated if, for example, the following applies: $$\text{SW}3\ge \text{Ueff}/\text{Ieff}\ge \text{SW}3\ast \left(1-\text{K}\right).$$

Alternatively or additionally, the quotient between the rms value Ieff of the alternating current and the rms value Ueff of the voltage can be formed and compared with the predetermined conductance threshold value in order to generate the presence signal Sa or the warning signal W.

It is also advantageous if the evaluation device 342 is connected to a position sensor which can detect the high position of the magnetic track brake 10 and generate a high position signal HLS which indicates the high position.

If such a high position signal HLS is present, evaluation device 342 can check whether the measurement data MA, for example the above-mentioned measured phase value V, deviates from a high position setpoint value stored for the high position beyond a predetermined high position tolerance measure or not. If the tolerance band defined by the high position tolerance measure is not left, the evaluation device 342 can output a signal which indicates that the magnetic track brake 10 is operating within the normal range; if the tolerance band is left, a maintenance signal Sw is preferably output, which indicates that the magnetic track brake 10 is to be serviced. The high position setpoint is defined, for example, by recording the measurement data MA after the initial installation and/or after each maintenance has been carried out, for example the measured phase value V is measured, and the measurement data MA, i.e. for example the measured phase value, is stored as the high position setpoint.

Advantageously, it can also be provided that the evaluation device 342 generates a cleavage signal Si when the measured phase value V falls below the high position setpoint minus the high position tolerance measure, and/or generates a wear signal Sv if the phase measured value V exceeds the high position setpoint plus the high position tolerance measure.

In addition, evaluation device 342 can generate a fault warning signal Sst if - for example from the position sensor already mentioned - there is a lowering signal ABS, according to which magnetic track brake 10 should be in the lowered state, i.e. on rail 20, but neither the contact signal Sa nor that Warning signal W is present. Such a fault warning signal Sst can indicate that, despite the presence of the lowering signal ABS, the magnetic rail brake 10 is either not seated on the rail 20 or the control device 34 is faulty.

In addition, the evaluation device 342 can generate its own high-level signal SH, for example if the measurement information MA explained above does not enable the generation of the contact signal Sa or the warning signal W, or if the AC behavior of the magnetic field generating device indicates a magnetic flux below a minimum flux threshold.

In the explanations above, it was assumed, for example, that the alternating source (here the alternating voltage source 341) generates a single alternating frequency; alternatively, the alternating source can also generate more than one frequency, for example a frequency spectrum in which at least one of the frequencies is preferably in the range between 10 and 40 Hz. The above steps for generating the measurement data MA and the signals such as the pad signal Sa, the warning signal W, the foliation signal Si, the maintenance signal Sw, the wear signal Sv and the fault warning signal Sst are preferably carried out for at least one of the Frequencies, particularly preferably for each of the frequencies performed.

In the case of two or more alternating frequencies, an analysis of the measurement signals can include a Fourier transformation, for example, in order to enable frequency-specific signal evaluation in a simple and rapid manner.

nur erläuternd beispielhaft zu verstehen. Im Falle, dass dieses physikalische Modell in der Praxis für bestimmte Bremskonfigurationen unzureichend ist und keine ausreichend genauen Ergebnisse liefert, wären geeignete Anpassungen und Ergänzungen des physikalischen Modells vorzunehmen, indem beispielsweise Modellparameter ergänzt und die Parameterwerte im Rahmen von Fit- oder Approximationsverfahren geschätzt werden, beispielsweise durch Vergleich tatsächlicher Messergebnisse mit modellbezogenen Simulationsergebnissen.The above explanations in connection with the 1 until 4 are only to be understood as examples; they are primarily intended for general understanding. In concrete terms, it should only be explained by way of example how measurement data MA relating to magnetic rail brake 10 can be formed on the basis of measurement results which describe the AC behavior of the magnetic field generating device. In this sense, the physical model used above, according to which the magnetic track brake 10 according to 1 can be described at least approximately by a series connection of an ohmic resistor R and an inductance L according to $$\text{Z}=\text{R}+\text{j}2\mathrm{\pi }\text{f L},$$

only to be understood as an example. In the event that this physical model is insufficient in practice for certain brake configurations and does not provide sufficiently accurate results, suitable adjustments and additions to the physical model would have to be made, for example by adding model parameters and estimating the parameter values in the context of fitting or approximation methods, for example by comparing actual measurement results with model-related simulation results.

Alternatively or additionally, the measurement information MA and signals based thereon can be generated solely on the basis of stored comparison values that have been measured and stored in the initial state after the initial installation of the magnetic track brake 10 or after maintenance. For example, measurement results that describe the AC behavior of the magnetic field generating device (such as the measured phase value V) can be measured and stored for the up position and the rest position (down position). By comparing the stored measurement results with current measurement results, it can be determined, for example, whether the magnetic track brake 10 is in the up position or the rest position, and a corresponding measurement data MA and a corresponding contact signal Sa or up position signal SH can be generated.

The other measurement data MA explained above and the other signals described above, such as the warning signal W, the foliation signal Si, the maintenance signal Sw, the wear signal Sv and the fault warning signal Sst, can also be formed by comparing the stored measurement results with current measurement results; the above statements apply accordingly in this regard.

The AC behavior of the magnetic field generating device can be detected during normal operation of the magnetic rail brake, for example when the direct current is switched on, or in the switched-off state, for example when the direct current is switched off, to generate the measurements and signals described above.

• - Die Magnetspule(n) können mit einer Messspannung beaufschlagt werden und es kann eine Messung von Wechselstromgrößen erfolgen. Die Messung der Wechselstromeigenschaften kann Informationen zur Position und zum Zustand der Magnetschienenbremse liefern.
• - Die Magnetschienenbremse kann zwei Bremsmagnete aufweisen oder aus solchen bestehen. Jeder Bremsmagnet kann als Induktivität mit Eisenkern und Spalt betrachtet werden. Daher kann der Zustand des Magneten mit Mitteln der klassischen Wechselstrommesstechnik beurteilt werden. Jede Änderung am Zustand des Eisenkerns führt zu Änderungen im Ansprechverhalten auf eine Wechselstrombeaufschlagung und kann damit sehr genau erfasst werden. Der Zustand eines neuwertigen Bremsmagneten in der Hochlage kann dabei als Referenzpunkt betrachtet werden. Wenn die Bremse nun aufsetzt, wird der Luftspalt geschlossen und das Wechselstromverhalten der Bremse erheblich geändert. Eine Messung der Wechselstromeigenschaften kann optimalerweise vor Fahrtantritt bei stehendem Fahrzeug durchgeführt werden. Dabei sind, da Vibrationen und sonstige Störeinflüsse minimal sind, die besten Ergebnisse zu erwarten.
• - Aufschieferungen schließen ebenfalls den Luftspalt, aber langsam und nicht vollständig. Sie können damit über einen Langzeitvergleich erkannt werden.
• - Durch Verschleiß wird Material abgetragen, was ebenfalls zu einer Änderung des Eisenkerns und damit des Wechselstromverhaltens führt. Auch hier kann eine Langzeitüberwachung durchgeführt werden.
• - Als Erweiterung ist es denkbar, auch während des Absenkvorgangs zu messen und dabei das Aufsetzen auf die Schiene zu erkennen. Dieses bietet eine hohe Sicherheit, da zwischen Annäherung an die Schiene und dem Aufsetzten auf dieselbe besser unterschieden werden kann.
• - Als Erweiterung ist eine Messung des Wechselstromverhaltens bei eingeschalteter Bremse denkbar. Dazu kann die herkömmliche Schalttechnik durch eine quasianaloge Endstufe ersetzt werden, welche den Messstrom aufmoduliert.
• - Eine technische Verbesserung kann darin liegen, die Wechselstrommessungen per Fouriertransformation in den Frequenzbereich zu übertragen. Dadurch wird die Messung von einigen Wechselstromeigenschaften vereinfacht.
• - Das beschriebene Verfahren kann die Diagnose zur Hochlagenerkennung um die Information ergänzen, ob die Magnetschienenbremse auch bis zur Schienenoberkante abgesenkt worden ist. Das Verfahren kann die Möglichkeit der Erkennung von Aufschieferungen bieten und somit eine Aussage zur Bremskraft der Magnetschienenbremse liefern.
• - Das Verfahren kann eine Erkennung des Verschleißzustandes der Polschuhe und Endglieder bieten, zumindest die Zustände Neu und Verschlissen.
• - Neben der Diagnose im Rahmen der Bremsprobe kann das Verfahren die Möglichkeit bieten, die Diagnose dynamisch, also auch während der Fahrt bzw. während der Bremsung durchzuführen. Die Diagnose zur Aufsetzerkennung sowie zur Aufschieferungs- und Verschleißerkennung kann ohne zusätzliche Sensorik erfolgen.
• - Die typischerweise zu verwendende Messtechnik kann ohne weiteren Aufwand die Messung des Innenwiderstandes der Bremse ermöglichen und kann damit zur Aufdeckung von Fehlern auf elektrischer Seite herangezogen werden.
• - Wenn eine Messtechnik verwendet wird, die auch im eingeschalteten Zustand messen kann, können weitere Schalt- und Löschglieder für die Magnetschienenbremsen entfallen.

The above exemplary embodiments can have one, several or all of the features and advantages listed below:

• - The magnetic coil(s) can be subjected to a measuring voltage and AC variables can be measured. Measuring the AC characteristics can provide information on the position and condition of the magnetic track brake.
• - The magnetic rail brake can have two brake magnets or consist of such. Each brake magnet can be considered as an inductor with an iron core and a gap. The condition of the magnet can therefore be assessed using classic AC measurement technology. Any change in the state of the iron core results in changes in the response to an AC load and can therefore be detected very accurately. The state of a new brake magnet in the up position can be used as a reference point. When the brake now touches down, the air gap is closed and the AC behavior of the brake changes significantly. A measurement of the AC properties can be carried out ideally before starting the journey with the vehicle stationary. The best results can be expected since vibrations and other disturbing influences are minimal.
• - Flaking also closes the air gap, but slowly and not completely. They can thus be identified via a long-term comparison.
• - Material is removed due to wear, which also leads to a change in the iron core and thus in the AC behavior. Long-term monitoring can also be carried out here.
• - As an extension, it is conceivable to also measure during the lowering process and thereby detect the touchdown on the rail. This offers a high level of security, since a better distinction can be made between approaching the rail and touching down on it.
• - As an extension, a measurement of the AC behavior when the brake is switched on is conceivable. For this purpose, the conventional switching technology can be replaced by a quasi-analog output stage, which modulates the measuring current.
• - A technical improvement can lie in transferring the AC measurements to the frequency domain using Fourier transformation. This simplifies the measurement of some AC characteristics.
• - The procedure described can supplement the diagnosis for high-level detection with the information as to whether the magnetic rail brake has also been lowered to the top edge of the rail. The method can offer the possibility of detecting sloughing and thus provide information on the braking force of the magnetic track brake.
• - The method can provide a detection of the state of wear of the pole pieces and end members, at least the New and Worn states.
• - In addition to the diagnosis as part of the brake test, the method can offer the possibility of carrying out the diagnosis dynamically, ie also while driving or braking. The diagnosis for detection of bottoming as well as for detection of splintering and wear can be carried out without additional sensors.
• - The measurement technology typically used can enable the internal resistance of the brake to be measured without any further effort and can therefore be used to detect faults on the electrical side.
• - If measuring technology is used that can also measure when switched on, further switching and suppression elements for the magnetic rail brakes can be omitted.

Finally, it should be mentioned that the features of all the exemplary embodiments described above can be combined with one another in any desired manner in order to form further other exemplary embodiments of the invention. All features of subclaims can also be combined with each of the independent claims, either individually or in any combination with one or other subclaims, in order to obtain further other exemplary embodiments.

Reference List

10

Magnetic track brake

11

magnetizable core

11a

pole shoe

11b

pole shoe

12

Magnetic field generating device (coil)

20

rail

30

control device

31

Switch

32

activation device

33

Direct current or DC voltage source

34

control device

341

alternate source

342

evaluation device

343

voltage measuring device

344

current measuring device

A1

electrical connection

A2

electrical connection

SECTION

lowering signal

e.g

magnetic river

bw

alternating flow

HLS

high position signal

i

direct current

In the

current reading

Iw

alternating current

MA

measurement

sat

signal

SH

elevation signal

si

foliation signal

Sst

malfunction warning signal

Sv

wear signal

sw

maintenance signal

t

Time

us

coil voltage

Uw

AC voltage

etc

voltage reading

V

phase reading

W

warning signal

Claims (15)

Monitoring device (34) for monitoring the function of a magnetic track brake (10), which comprises at least one magnetic field generating device (12) for generating a magnetic field and is designed in such a way that it rests on a trackside rail (20) in active braking mode and is raised and raised in the inactive state is separated from the rail (20), characterized in that the control device (34) comprises: - an alternating source (341) for generating an alternating current (Iw) through the magnetic field generating device (12) or at least an alternating current component in a through the magnetic field generating device (12 ) flowing current and for generating an alternating magnetic field and - an evaluation device (342) which is designed to, on the basis of measurement results which describe the AC behavior of the magnetic field generating device (12), at least one measurement information (MA) relating to the magnetic track brake (10) to build. Control device (34) after claim 1 , characterized in that - the control device (34) has a voltage measuring device (343) for measuring a voltage present at the magnetic rail brake (10), the magnetic field generating device (12) or the alternating source (341) and a current measuring device (344) for measuring the magnetic field generating device (12) and - the evaluation device (342) is designed to form the at least one measurement indication (MA) on the basis of measurement results that are supplied by the voltage measurement device (343) and the current measurement device (344). Control device (34) according to one of the preceding claims, characterized in that the evaluation device (342) is designed in such a way that it generates a contact signal (Sa) indicating contact of the magnetic rail brake (10) on the rail (20) depending on whether the at least one measurement (MA) satisfies a seating condition. Control device (34) according to one of the preceding claims 2 until 3 , characterized in that the evaluation device (342) is designed in such a way that, on the basis of measurement results supplied by the voltage measuring device (343) and the current measuring device (344), a measured phase value (V) indicating the phase shift between current and voltage forms, the measured phase value (V) forming the at least one measurement indication (MA) or one of the measurement indications (MA), and generating the pending signal (Sa) if the phase measurement value (V) reaches or exceeds a predetermined phase shift threshold value. Control device (34) according to one of the preceding claims 2 until 4 , characterized in that the evaluation device (342) is designed such that on the basis of measurement results from the voltage measuring device (343) and the current measuring device (344) are supplied, forms an impedance vector describing an impedance of the magnetic field generating device (12), the absolute value of the impedance vector forming the at least one measurement data (MA) or one of the measurement data (MA), and generates the signal (Sa) when the amount of the impedance pointer reaches or exceeds a predetermined impedance magnitude threshold value. Control device (34) according to one of the preceding claims 2 until 5 , characterized in that the evaluation device (342) is designed in such a way that it forms an impedance vector describing an impedance of the magnetic field generating device (12) on the basis of the measurement results supplied by the voltage measuring device (343) and the current measuring device (344), the phase angle of the Impedance pointer which forms at least one measurement (MA) or one of the measurements (MA), and generates the signal (Sa) when the phase angle of the impedance pointer reaches or exceeds a predetermined angle threshold. Control device (34) according to one of the preceding claims 2 until 6 , characterized in that the measurement results of the voltage measuring device (343) and the current measuring device (344) indicate effective or peak values of the current or the voltage and the evaluation device (342) is designed in such a way that it generates the signal (Sa) when - a quotient forming the at least one measurement (MA) between the rms or peak value of the voltage and the rms or peak value of the current reaches or exceeds a predetermined resistance threshold value, and/or - a quotient forming the at least one measurement (MA) between the rms - or peak value of the current and the rms or peak value of the voltage reaches or falls below a specified conductance threshold value. Control device (34) according to one of the preceding claims 2 until 7 , characterized in that the evaluation device (342) comprises a Fourier transformation device and is designed in such a way that it subjects the time profile of current and voltage measured values of the voltage measuring device (343) and the current measuring device (344) to a Fourier transformation with formation of a spectrum and the pending signal ( Sa) generated as a function of the spectrum. Control device (34) according to one of the preceding claims, characterized in that - the alternating source (341) is or has an alternating current source or alternating voltage source which feeds an alternating current (Iw) into the magnetic field generating device (12), and/or - the alternating source (341 ) is or has a modulation device which modulates the amplitude of the current flowing through the magnetic field generating device (12) over time to form the alternating current or alternating current component. Monitoring device (34) according to one of the preceding claims, characterized in that - the alternating current (Iw) or alternating current component is sinusoidal over time or - the alternating current (Iw) or alternating current component has two or more frequencies in the frequency spectrum. Control device (34) according to one of the preceding claims, characterized in that the frequency or at least one of the frequencies of the alternating current (Iw) or the alternating current component lies in the frequency range between 10 and 40 Hz. Control device (34) according to one of the preceding claims, characterized in that the evaluation device (342) is designed in such a way that it generates a cleavage signal (Si) which indicates that at the interface to the rail (20) on the magnetic rail brake (10) Deposits are generated depending on whether the at least one measurement (MA) meets a foliation condition. Control device (34) according to one of the preceding claims, characterized in that - the evaluation device (342) is designed in such a way that it sends a wear signal (Sv) which indicates the state of wear of pole shoes (11a, 11b) and end members of the magnetic track brake (10). , generated depending on whether the at least one measurement (MA) meets a wear condition, and / or - the evaluation device is designed such that it generates a high signal when the at least one measurement meets a high condition. Control device (34) according to one of the preceding claims, characterized in that the evaluation device (342) is designed in such a way that it generates a fault warning signal (Sst), which indicates that the function of the magnetic track brake (10) is faulty, if - although a lowering signal (ABS) is present, after which the magnetic rail brake (10) should rest on the rail (20) - the at least one Messan output (MA) indicates the fulfillment of a predetermined fault condition. Method for monitoring the function of a magnetic rail brake (10), which comprises at least one magnetic field generating device (12) for generating a magnetic field, wherein the magnetic rail brake (10) is designed in such a way that it rests on a track-side rail (20) during active, fault-free braking operation and raised in the inactive state and separated from the rail (20), characterized in that - a current in the form of an alternating current (Iw) or at least a current with an alternating current component is fed into the magnetic field generating device (12) to generate an alternating magnetic field and - on at least one measurement information (MA) relating to the magnetic rail brake (10) is formed on the basis of measurement results which describe the AC behavior of the magnetic field generating device (12).

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