Rotation angle detection system for a rotation angle detection system of a rotary brake drive for a rail vehicle

Description

[0001] The present invention relates to a rotation angle detection system for a rotation angle detection system of a rotary brake drive for a rail vehicle, as well as a brake system for a rail vehicle and a rail vehicle with such a rotation angle detection system.

[0002] In rail vehicles, for example, electromechanical brake actuators, such as brake cylinders, are designed so that electrical energy is converted into mechanical energy using an electric motor. When the brake actuator or brake cylinder is activated, the rotor in the electric motor rotates. This rotational movement is then transferred to a spindle nut fixed inside a hollow shaft. Because the rotating spindle nut is fixed axially, this results in a feed motion of the spindle. In a further step, an eccentric shaft lever rotates an eccentric shaft and actuates the clamping levers. The clamping levers then press the brake pads, which are mounted in holders, against a rotating brake disc to generate braking force. To release the brake, the electric motor rotates in the opposite direction, thus reversing the threaded drive.

[0003] A rotary encoder is used to control the electric motor, for example, a permanent magnet synchronous machine (PMSM), to detect the rotor position. In addition to the rotary encoder, the brake actuator housing can also contain other sensors as well as electrical and mechatronic components, such as limit switches, load rings, or motor braking devices. Due to the possibility of installation in a bogie, there are increased requirements for high-voltage and insulation resistance, also known as HV / ISO resistance. This particularly affects the increased system voltage of 110 V instead of 48 V that can be used for a brake actuator. For example, during a type test, an HV / ISO resistance of 500 VAC at 50 Hz or 750 VDC at 48 V must be achieved for a duration of 60 seconds, whereas at 110 V, this must be 1000 VAC at 50 Hz or 1500 VDC.Furthermore, in this example, a 10-second high-voltage / isolation (HV / ISO) resistance of 500 VAC at 50 Hz or 750 VDC at 48 V, and 1000 VAC at 50 Hz or 1500 VDC at 110 V, may be required. These requirements are applicable here as examples to configurations where no prior galvanic isolation is performed and, for example, 110 V is transmitted directly from the railway vehicle lines. Corresponding tests are carried out between the housing of the respective components and the electronics or the current-carrying components, such as windings, cable outlets, and the like.

[0004] In principle, higher voltage / insulation resistance can be achieved by increasing the insulation to electrically conductive components and contact surfaces. This can be accomplished either by increasing the internal insulation distance between live and corresponding housing parts of the sensors, or by using more non-conductive materials, such as plastic, in greater quantities. For example, the insulation of electrical cables can be reinforced, or the insulation distances on electronic circuit boards can be increased, and more suitable components for higher voltage classes, such as ESD capacitors rated for 1 kV and above, can be selected.

[0005] Specifically, many standard sensors and components currently available on the market do not possess the required high HV / ISO resistance, particularly considering the increased demands of a 110 V system voltage. To meet these higher requirements, manufacturers must implement customer-specific modifications, such as better insulated winding wires, housings with plastic sheathing, and / or the replacement of electronic components. Such modifications typically involve greater effort, increased development costs, higher unit prices, and reduced availability.

[0006] Ultimately, the measures listed above for increasing HV-ISO strength necessitate modifications to the sensor that deviate from the standard product. While this fulfills the increased HV-ISO strength requirements, it also introduces the aforementioned and other disadvantages. From a technical perspective, such modifications can result in shorter lifespans, for example, in plastic housings, and require more installation space, for instance, due to thicker wire diameters. Furthermore, such modifications can restrict the application range, as limitations may arise due to potential vibrations or shock loads, temperature profile restrictions, environmental stresses, and / or limited installation options.

[0007] In this context, US 2017 / 182984 A1 concerns an electric braking system in which, among other things, a motor angle is estimated via an angle sensor as a rotation angle estimation device.

[0008] EP 3 078 876 A1 relates to an electric braking device for a vehicle, in which a rotor position of an electric motor is detected via a rotary angle sensor.

[0009] EP 0 984 190 A2 also relates to an electric braking device. A rotary angle sensor is used here to detect the angle of rotation of a rotating shaft.

[0010] EP 3 858 688 A1 relates to an electric brake with a rotary angle sensor for detecting the rotational position of an electric motor.

[0011] EP 0 982 210 A2 relates to an electric braking device, wherein a rotary angle sensor detects a rotary angle of a rotating shaft of a brake motor.

[0012] In view of the foregoing, the object of the present invention is therefore to provide an improved rotary angle detection system compared to the prior art, in particular with regard to increased voltage / insulation resistance with the simplest and therefore most cost-effective configuration possible.

[0013] This task is solved by the subject matter of the independent claims. Advantageous further developments are the subject matter of the dependent claims.

[0014] According to the invention, a rotation angle detection system for a rotation angle detection of a rotary brake drive for a rail vehicle comprises at least one sensor unit for detecting a rotation angle, which can be operationally connected to the rotary brake drive, and at least one main electronic path for transmitting control signals and / or sensor signals, wherein the at least one main electronic path can be operationally connected to the at least one sensor unit, wherein the at least one main electronic path comprises at least one signal transmitter, which divides the main electronic path into an electronic main path section facing the sensor unit from the signal transmitter and an electronic main path section facing away from the sensor unit from the signal transmitter, and wherein the at least one signal transmitter is configured to galvanically isolate the sensor unit from the electronic main path section facing away from the sensor unit.

[0015] The basic idea of ​​the present invention is to shift the realization of HV / ISO resistance to a different area of ​​the system chain. Accordingly, for example, the sensor unit or a corresponding sensor within the sensor unit does not need to be modified and can therefore continue to be manufactured as a standard product. Instead, the sensor unit or the corresponding sensor is galvanically isolated in a main electronics path as a signal and / or control path for the sensor unit, for example, in the form of electrical leads. A component can be used as the signal transmitter for galvanic isolation that, due to its significantly simpler design, can provide the required HV / ISO resistance more cost-effectively. This allows the remaining electronics in the overall system to be galvanically isolated in a simpler manner to meet the higher requirements.

[0016] The operational connectivity of the main electronic path encompasses both direct and indirect connections between individual signal transmission paths. Furthermore, the operational connection can also refer to the actual activation of the main electronic path or components within it, such as a signal conditioning unit. In other words, at least one main electronic path might be physically connected to the sensor unit at all times, but strictly speaking, an operational connection only occurs when the corresponding signal conditioning unit is activated.

[0017] The operational connection between the sensor unit and the rotary brake drive can be either direct or indirect. This connection can be mechanical and / or signal-based. The sensor unit can thus generate a signal representing a rotation angle, either through direct contact or via optical, acoustic, and / or electrical or electromagnetic signals interacting with the rotary brake drive. This signal can then be transmitted via the main electronics path to a signal processing unit or similar device.

[0018] According to one embodiment, the rotary angle detection system further comprises at least one electronic safety path for transmitting control signals and / or sensor signals, wherein the at least one electronic safety path is operationally connectable to the at least one sensor unit, wherein the at least one electronic safety path comprises at least one signal transmitter which divides the electronic safety path into an electronic safety path section facing the sensor unit from the signal transmitter and an electronic safety path section facing away from the sensor unit from the signal transmitter, and wherein the at least one signal transmitter is configured to galvanically isolate the sensor unit from the electronic safety path section facing away from the sensor unit.

[0019] The main electronics path and the safety electronics path are separate individual paths that are either connected in parallel or run completely independently. The main electronics path can be understood as the path that is operationally connected to the sensor unit during normal operation, enabling the unidirectional or bidirectional transmission of sensor signals or other signals, such as control signals. Conversely, the safety electronics path can only be operationally connected to the sensor unit if a fault prevents or otherwise disrupts transmission via the main electronics path.Alternatively, the main electronics path and the electronics safety path can be operationally connected to the sensor unit simultaneously, at least temporarily. This allows for plausibility checks of the transmitted signals or ensures that signals can be transmitted without delay via the electronics safety path even if the main electronics path fails. The operational connectivity of the electronics safety path, similar to that of the main electronics path, encompasses both direct and indirect connections between the individual paths for signal transmission. Furthermore, the operational connection can also refer to the actual activation of the individual paths or their respective signal processing units.

[0020] The configuration of the rotary angle detection system with one main electronics path and one safety electronics path can refer to a redundant design of the rotary angle detection system. The basic idea is that instead of two or more complete sensor paths, each containing both the sensor unit itself and, for example, a signal conditioning unit such as corresponding signal processing electronics, one sensor unit with two or more signal conditioning units is used to achieve redundancy, with at least one of the signal conditioning units assigned to a main electronics path and at least one of the signal conditioning units assigned to a safety electronics path.

[0021] By designing the rotary angle detection system with a sensor unit featuring redundant individual paths, a reduction in the required installation space can be achieved, particularly by implementing the respective signal processing units using small microelectronic and / or highly integrated components. Even with redundant individual paths, these components require comparatively little space. The redundant design of the individual paths—that is, the electronic safety path in relation to the main electronic path or the respective signal processing units—can refer to identical functionality or to redundancy of predetermined, especially safety-relevant, functions.

[0022] The electronic safety path can also be configured as an independent electronic functional path that performs further functions independently of or in addition to a redundancy function and / or provides for alternative signal transmission. In such a configuration, the electronic safety path is not strictly speaking a standalone safety path, but rather a second electronic functional path.

[0023] The configuration with at least one main electronics path and at least one safety electronics path also represents a configuration principle for a rotary angle detection system that can be used independently of the increase in HC / ISO strength, offering synergies but also allowing independent use.

[0024] Independently considered, the disclosure thus provides a rotation angle detection system for the rotation angle detection of a rotary brake drive for a rail vehicle, comprising at least one sensor unit for detecting a rotation angle which can be operationally connected to the rotary brake drive, and having at least one main electronic path and at least one safety electronic path per sensor unit, wherein the at least one main electronic path and the at least one safety electronic path can each be operationally connected to the at least one sensor unit as a single path, and wherein the at least one main electronic path and the at least one safety electronic path each have at least one signal processing unit.

[0025] According to one embodiment of the disclosure of the redundant rotary angle detection system, the sensor unit is equipped with a higher fault tolerance than the at least one electronics main path and / or the at least one electronics safety path. In particular, the sensor unit exhibits indelible properties with regard to the higher fault tolerance.

[0026] Accordingly, the sensor unit, such as a single sensor element, is designed to be simple, reliable, and fail-safe to achieve the highest possible reliability. This can be achieved, for example, through suitable measures such as a durable mechanical design, reinforced insulation, larger conductor cross-sections, and / or the use of age-resistant materials. In particular, the sensor unit is designed so that its properties remain unchanged over a defined operating period or even its entire lifespan. The term "unfailingly unchanged properties" in this context refers to an unforeseeable failure. Since the signal conditioning units and the associated individual paths are implemented redundantly, at least in predefined functionalities, functionalities with lower reliability can be assigned to these individual paths.Especially with regard to a signal processing unit with corresponding components that are usually comparatively more complex and have a higher probability of failure, the higher probability of failure can be at least partially compensated for by redundancy.

[0027] According to one embodiment of the disclosure of the redundant rotary angle detection system, the signal processing unit of the at least one main electronics path and / or the at least one safety electronics path includes at least one signal converter.

[0028] At least one signal converter can, for example, convert sensor signals transmitted by the sensor unit into signals that can be processed by further signal conditioning components. The signal converter can be, for example, an analog-to-digital converter (ADC) that converts an analog signal from the sensor unit into a digital format.

[0029] According to one embodiment of the disclosure of the redundant rotary angle detection system, the signal processing unit of the at least one main electronics path and / or the at least one safety electronics path includes at least one signal processing unit.

[0030] For example, the signal processing unit further processes the signal from the sensor unit, which may have been previously converted via the signal converter. This further processing can include, among other things, a calculation into a different quantity taking into account additional signal inputs, and / or another form of signal processing to determine a rotation angle of the rotary brake drive based on the signal from the sensor unit.

[0031] According to one embodiment of the disclosure of the redundant rotary angle detection system, the signal processing unit of the at least one main electronic path and / or the at least one safety electronic path has at least one signal output unit.

[0032] The signal output unit outputs the rotation angle of the rotary brake drive, determined based on the signal from the sensor unit. The signal output unit can be a separate unit from the signal processing unit or it can be integrated into the aforementioned signal processing unit. Conversely, the signal output unit can also include signal processing functions.

[0033] According to one embodiment of the disclosure of the redundant rotary angle detection system, the at least one electronics main path and / or the at least one electronics safety path has at least one signal switch via which the at least one signal processing unit can be operationally connected to the at least one sensor unit.

[0034] A signal switch like this allows at least one main electronic path and / or at least one safety electronic path to be selectively connected to and disconnected from the sensor unit. If a fault in at least one main electronic path and / or at least one safety electronic path could be transmitted to the sensor unit or otherwise negatively affect it, this is prevented by disconnecting the faulty individual path. Furthermore, the signal switch can also be used to selectively connect to the sensor unit. For example, initially only one individual path can be connected to the sensor unit, and then, if this individual path fails or for other reasons, the other individual path is activated or switched to via the signal switch.The term "connecting" refers to the linking of both individual paths, while "switching" involves disconnecting the previous individual path.

[0035] According to one embodiment of the disclosure of the redundant rotary angle detection system, the at least one electronics main path and / or the at least one electronics safety path includes at least one power supply unit that can be operationally connected to the at least one sensor unit.

[0036] The sensor unit therefore does not necessarily require its own power supply, but can be powered via at least one main electronics path and / or at least one safety electronics path. If both the main electronics path and / or the safety electronics path have at least one power supply unit or a corresponding connection to a power supply unit, the reliability can be further increased.

[0037] According to one embodiment of the disclosure of the redundant rotary angle detection system, the at least one electronics main path and / or the at least one electronics safety path has or has at least one power supply switch via which the at least one power supply unit can be operationally connected to the at least one sensor unit.

[0038] Similar to a signal switch, a targeted connection and disconnection of the respective power supply unit can also be carried out here.

[0039] The various embodiments of the disclosure of the redundant rotary angle detection system are applicable, either individually or in combination, to the rotary angle detection system of the present invention in relation to a configuration with an electronic safety path.

[0040] According to one embodiment, the at least one sensor unit is arranged in a sensor unit housing, and the at least one signal transmitter of the electronics main path and / or the electronics safety path forms the signal input and / or signal output of the electronics main path and / or the electronics safety path into and / or from the sensor unit housing.

[0041] The at least one signal transmitter thus forms an interface for the sensor unit, so that the signal transmitter can also be easily retrofitted. In particular, the signal transmitter can be arranged as an interface of the sensor unit housing, i.e., in or on the sensor unit housing.

[0042] According to one embodiment, the at least one signal transmitter of the main electronics path and / or the safety electronics path is a signal transformer, a digital isolator or an optocoupler, or comprises at least a signal transformer, a digital isolator and / or an optocoupler.

[0043] Galvanic isolation can be achieved, for example, using relatively small transformers as signal transmitters, which can be placed before the sensor's inputs and outputs and on printed circuit boards. This is a relatively cost-effective technique for the analog interfaces to the sensor unit. However, with this approach, the space required on the circuit board and the overall height must be considered, as the transformer needs to be made correspondingly larger with increasing input voltage. Optocouplers can be used for this purpose, as well as for the subsequent digital signal transmission.

[0044] Alternatively or additionally, galvanic isolation can also be achieved via digital interfaces. Since modern sensors often require further digital signal processing and transmit the necessary measured values ​​to the system via digital interfaces, digital isolators can be used at this system boundary. These digital isolators can be designed as individual electronic components in the form of an integrated circuit and enable the reliable isolation of signal and power supply lines, as well as communication and data interfaces, to meet the higher HV / ISO strength requirements. As mentioned above, an optocoupler can also be used as a digital isolator with appropriate configuration.

[0045] According to one embodiment, at least one sensor unit is a resolver or has at least one resolver.

[0046] A resolver is a rotary angle sensor, similar to an electric motor, and consists of a rotor and a stator. The resolver's rotor can be made of a highly magnetically conductive material and forms the magnetic feedback loop for the magnetic field generated by the stator. Looking at the winding in the resolver's stator, two distinct areas can be identified. The first area corresponds to a rotary transformer, with the winding arranged concentrically around the rotor. In the second area, the winding configuration resembles a two-phase motor winding, but the phases are not connected. The two winding areas are spatially separated and magnetically coupled only by the rotor and the stator feedback loop. For example, the resolver's excitation winding is driven with a sinusoidal or rectangular, high-frequency voltage, typically in the range of 2 kHz to 10 kHz.The alternating magnetic field is transferred by the rotor exclusively to the measuring windings and its amplitude is modulated. The voltages in the measuring windings can be used as evaluation parameters. A sine wave and a cosine wave are then provided as output signals. Since the magnetic excitation of the rotor is achieved with an alternating voltage of constant amplitude, it induces a voltage in the measuring windings whose amplitude is independent of the rotational speed of the brake drive shaft. The amplitudes of the voltages in the measuring windings therefore depend only on the rotor angle.

[0047] Due to the resolver's design, which does not use any mechanical components subject to wear, such as ball bearings, nor any electronic components, such as microprocessors, semiconductors or solid electrolyte capacitors, the resolver itself offers a very high level of reliability.

[0048] In particular, the main electronics path and / or the electronics safety path includes at least one resolver digital converter, which is specifically configured to magnetically excite a rotor of the resolver, preferably with an alternating voltage of constant amplitude, and to receive sine and cosine signals from a stator of the resolver.

[0049] By using at least one resolver-to-digital converter (DDC), the resolver can be easily operated as a sensor unit. The DDC can be used for both controlling and processing the resolver's measurement data. Information about the measured quantities can be transmitted from the resolver-to-digital converter to a higher-level system, such as a microcontroller or an FPGA (Field Programmable Gate Array), via a digital interface, such as an SPI interface.

[0050] In particular, at least one excitation signal switch for is / are arranged between the resolver-digital converter in the main electronics path and / or in the electronics safety path and the resolver for isolating and connecting the resolver-digital converter and the resolver with respect to an excitation signal path in the main electronics path and / or electronics safety path, at least one sine signal switch for isolating and connecting the resolver-digital converter and the resolver with respect to a sine signal path in the main electronics path and / or electronics safety path, and / or at least one cosine signal switch for isolating and connecting the resolver-digital converter and the resolver with respect to a cosine signal path in the main electronics path and / or electronics safety path.

[0051] The transmission of excitation signals, sine signals, and / or cosine signals can thus be switched between the resolver-digital converter in the main electronics path and / or in the safety electronics path and the resolver via the respective excitation signal switch, sine signal switch, or cosine signal switch. The respective disconnection and connection can be triggered by a fault condition that initiates a switch from a main electronics path to a safety electronics path. Alternatively or additionally, disconnection and connection can also be implemented in the event of a detected voltage surge, thus providing overvoltage protection.

[0052] According to a further training, at least one resolver-digital converter and / or a signal processing unit is / are designed to determine a rotational angular position of the resolver from the sine and cosine signals of the stator of the resolver, in particular taking into account a number of pole pairs of the resolver.

[0053] The resolver signals, i.e., the sine and cosine signals, are evaluated, for example, by calculating the arctangent, which allows the electrical rotational position to be output. By including the number of pole pairs of the resolver, output as a mechanical rotational position is also possible. Furthermore, the resolver can be diagnosed using the two output signals and the application of trigonometric calculations.

[0054] According to one embodiment, the at least one resolver digital converter is arranged in the main electronics path and / or in the electronics safety path in the section of the main electronics path or the section of the electronics safety path facing the sensor unit.

[0055] The at least one resolver digital converter in the main electronics path and / or in the electronics safety path can thus be equally protected by the signal transmitter for galvanic isolation or be galvanically isolated from the main electronics path section or electronics safety path section facing away from the sensor unit.

[0056] According to one embodiment, the rotation angle detection system has at least one sensor unit and a safety path sensor unit as a further sensor unit, wherein the at least one electronic safety path can be operationally connected to the safety sensor unit.

[0057] For example, with regard to redundancy or the detection of different sensor signals, not only can the at least one sensor unit be connected to the main electronics path and the electronics safety path as individual paths, but the electronics safety path can also be operationally connected to another sensor unit that is different from the at least one sensor unit.

[0058] In particular, the sensor unit and the safety path sensor unit have different measuring principles or different measuring configurations.

[0059] The different measurement principle or configuration can relate to determining the same measurand, namely the angle of rotation. Alternatively or additionally, it can also be used to determine another measurand that supports the determination of the angle of rotation, further specifies it, or can even operate independently. Regarding different measurement principles for determining a single measurand, in this case the angle of rotation, the sensor unit can be the resolver described above, while the other sensor unit is a Hall sensor. As an example of a different measurement configuration, both the sensor unit and the other sensor unit could be resolvers, but controlled with different excitation signals depending on the operating mode of the rotary brake drive.

[0060] According to one embodiment, the rotation angle detection system has at least one signal processing unit in the main electronics path in the section of the main electronics path facing away from the sensor unit and at least one signal processing unit in the safety electronics path in the section of the safety electronics path facing away from the sensor unit.

[0061] The at least one signal processing unit in the main electronics path and the electronics safety path is thus galvanically isolated from the at least one sensor unit via the signal transmitter. The possibility of corresponding signal processing via the main electronics path and the electronics safety path also allows for the aforementioned redundant signal processing.

[0062] According to one embodiment, the rotary angle detection system has at least one signal processing unit and at least one further signal processing unit in the main electronics path in the section of the main electronics path facing away from the sensor unit, wherein the at least one signal processing unit and the at least one further signal processing unit are connected in parallel.

[0063] Here too, at least one signal processing unit and at least one other signal processing unit are galvanically isolated from at least one sensor unit by the signal transmitter. The same sensor signal can be transmitted to both signal processing units via the main electronics path. The parallel connection allows for redundant signal processing of the sensor signal.

[0064] According to a further aspect, the present invention relates to a braking system for a rail vehicle, comprising at least one brake actuator for applying a braking force, at least one rotary brake drive for actuating the brake actuator, and at least one rotation angle detection system as described above.

[0065] The features described in the preceding and following description of the rotation angle detection system relate equally to advantageous further developments of the braking system according to the invention and vice versa.

[0066] According to a further aspect, the present invention relates to a rail vehicle with at least one rotation angle detection system and / or a braking system as described above, wherein at least the sensor unit is arranged in a bogie of the rail vehicle.

[0067] The features described in the preceding and following description of the rotation angle detection system relate equally to advantageous further developments of the rail vehicle according to the invention and vice versa.

[0068] The embodiments of the invention described above and below are not to be considered as limiting to the subject matter of the invention. Rather, further subject matter according to the invention can be obtained by adding, omitting, or exchanging individual features.

[0069] Preferred embodiments of the invention are described below with reference to the accompanying drawings.

[0070] In detail, they show Fig. 1 a schematic representation of a rotation angle detection system for a rail vehicle according to an exemplary first embodiment; Fig. 2 a schematic representation of a rotation angle detection system for a rail vehicle according to an exemplary second embodiment; Fig. 3 a schematic representation of a rotation angle detection system for a rail vehicle according to an exemplary third embodiment; and Fig. 4 a schematic representation of a rotation angle detection system for a rail vehicle according to an exemplary fourth embodiment.

[0071] Fig. 1 Figure 1 shows a schematic representation of a rotation angle detection system 1 for a rail vehicle according to an exemplary first embodiment. The rotation angle detection system 1 has a resolver 20 as an exemplary sensor unit, which can transmit sensor signals corresponding to a rotation angle of a motor 10, as an exemplary rotary brake drive, to a main electronic path and a safety electronic path, which will be described later. The motor 10 is controlled via a motor drive controller 90, which transmits signals from a power supply 60 to the motor 10, taking into account a signal processing unit 70 related to the main electronic path and a signal processing unit 80 related to the safety electronic path.As shown here, the power supply in a train 100 is arranged as a higher-level system unit of a rail vehicle, while the other components shown are assigned to a brake actuator 200, which in the illustrated embodiment is provided in a bogie. The respective connections between the signal processing unit 70 and the signal processing unit 80 with the motor drive control 90 can be interrupted and re-established via respective signal output switches 71, 81.

[0072] The main electronics path connects the resolver 20 to the signal processing unit 70, which is associated with the main electronics path. To control the resolver 20, the signal processing unit 70 controls a resolver-to-digital converter 30 via the main electronics path. The resolver-to-digital converter, in turn, transmits an excitation signal to the resolver 20 via the main electronics path according to the control signal. The connection between the resolver-to-digital converter 30 and the resolver 20 can be disconnected and reconnected via an excitation signal switch 31 in the main electronics path. In response to the excitation signal, in conjunction with the rotation angle of the motor 10, the resolver 20 transmits sine and cosine signals via separate signal paths in the main electronics path to the resolver-to-digital converter 30, which then transmits corresponding signals to the signal processing unit 70.The respective signal connections between the resolver digital converter 30 and the resolver 20 can be disconnected and reconnected in the same way via a sine signal switch 32 and a cosine signal switch 33 in the main electronics path.

[0073] Analogous to the main electronics path, the electronics safety path is configured, serving here as an example of a redundant electronics safety path. Accordingly, the electronics safety path connects the resolver 20 to the signal processing unit 80, which is assigned to the electronics safety path. To control the resolver 20, the signal processing unit 80 controls a resolver-to-digital converter 40 via the electronics safety path, which in turn transmits an excitation signal to the resolver 20 via the electronics safety path as controlled. The connection between the resolver-to-digital converter 40 and the resolver 20 can be disconnected and reconnected via an excitation signal switch 41 in the main electronics path.In response to the excitation signal in conjunction with the rotation angle of the motor 10, the resolver 20 transmits sine and cosine signals via separate signal paths in the electronic safety path to the resolver-digital converter 40, which then transmits corresponding signals to the signal processing unit 80. The respective signal connections between the resolver-digital converter 40 and the resolver 20 can be disconnected and reconnected via a sine signal switch 42 and a cosine signal switch 43 in the electronic safety path.

[0074] For galvanic isolation of the resolver 20 from the other aforementioned components in the main electronics path and the electronics safety path, an excitation signal transformer 51 is arranged in the signal path for the excitation signal between the excitation signal switch 31 or 41 and the resolver 20, a sine signal transformer 52 is arranged in the signal path for the sine signal between the sine signal switch 32 or 42 and the resolver 20, and a cosine signal transformer 53 is arranged in the signal path for the cosine signal between the cosine signal switch 33 or 43 and the resolver 20. The respective transformers 51, 52, and 53 isolate the corresponding signal path in a corresponding signal path section facing the resolver 20 and a corresponding signal path section facing away from the resolver 20. The resolver 20 is arranged here in a sensor unit housing 3.In the illustrated embodiment, the respective signal transformers 51, 52, 53 for galvanic isolation are designed as housing interfaces of the sensor unit housing 3 or are integrated accordingly into an interface area of ​​the sensor unit housing 3. Thus, the signal path section facing the resolver 20 is arranged in the sensor unit housing 3, while the signal path section facing away from the resolver 20 is assigned to a region of a battery potential 2.

[0075] The configuration described above, with signal transformers 51, 52, 53 connected to the signal feed lines to resolver 20, allows the continued use of a standard resolver with a metallic housing, which offers advantages in terms of cost, durability, and availability. The signal transformers 51, 52, 53 are also relatively inexpensive and may exhibit only slightly higher failure rates, for example, +30 FIT (failure in time). To reduce the space required for the signal transformers 51, 52, 53, a reduction in resolution and / or a reduction in the supply voltage for resolver 20, for example from 7 Vrms to 1 Vrms, can be considered, depending on the available installation space.

[0076] Fig. 2 Figure 1 shows a schematic representation of a rotation angle detection system 1' for a rail vehicle according to an exemplary second embodiment. The rotation angle detection system 1' of the second embodiment differs from the rotation angle detection system 1 of the first embodiment in that the rotation angle detection system 1' provides galvanic isolation between the signal processing unit 70 and the resolver-digital converter 30 in the main electronics path and galvanic isolation between the signal processing unit 80 and the resolver-digital converter 40 in the electronics safety path, instead of the galvanic isolation directly following the resolver 20 by the signal transformers 51, 52, 53. For this purpose, the resolver 20, the resolver-digital converter 30, the excitation signal switch 31, the sine signal switch 32, and the cosine signal switch 33 of the main electronics path are arranged in a sensor unit housing 3'.To galvanically isolate the resolver 20, the resolver-digital converter 30, the excitation signal switch 31, the sine signal switch 32, and the cosine signal switch 33 from the signal processing unit 70, a digital isolator 54 is provided in the main electronics path. This isolator divides the main electronics path into a section facing the resolver 20 and a section facing away from the resolver 20. The digital isolator 54 is configured to provide galvanic isolation between the section facing the resolver 20, containing the resolver-digital converter 30, the excitation signal switch 31, the sine signal switch 32, and the cosine signal switch 33, and the section facing away from the resolver 20, containing the signal processing unit 70. In the embodiment shown, the digital isolator 54 is designed as a housing interface of the sensor unit housing 3.accordingly integrated into an interface area of ​​the sensor unit housing 3. The main electronic path section facing the resolver 20 is therefore arranged in the sensor unit housing 3', while the main electronic path section facing away from the resolver 20 is assigned to a region of a battery potential 2'.

[0077] To provide galvanic isolation between the resolver 20, the resolver-digital converter 40, the excitation signal switch 41, the sine signal switch 42, and the cosine signal switch 43 from the signal processing unit 80, a digital isolator 55 is provided in the electronic safety path, analogous to the main electronic path. This isolator divides the electronic safety path into a section facing the resolver 20 and a section facing away from the resolver 20. The digital isolator 55 is configured to provide galvanic isolation between the section facing the resolver 20, containing the resolver-digital converter 40, the excitation signal switch 41, the sine signal switch 42, and the cosine signal switch 43, and the section facing away from the resolver 20, containing the signal processing unit 80.In the illustrated embodiment, the digital isolator 55 is designed as a housing interface of the sensor unit housing 3 or is integrated accordingly into an interface area of ​​the sensor unit housing 3. Accordingly, the electronic safety path section facing the resolver 20 is arranged in the sensor unit housing 3', while the electronic safety path section facing away from the resolver 20 is assigned to a battery potential 2' area.

[0078] The digital isolators 54 and 55 are therefore connected upstream of the respective resolver-digital converters 30 and 40 from the respective signal processing units 70 and 80 towards the resolver 20 in order to enable galvanic isolation of the supply voltage and the digital I / O interfaces. In a redundant configuration with a main electronics path and a backup electronics path, a digital isolator 54 or 55 must therefore be provided for each signal path.

[0079] Furthermore, the explanations regarding the first embodiment can be applied analogously to the second embodiment.

[0080] Fig. 3 Figure 1 shows a schematic representation of a rotation angle detection system 1" for a rail vehicle according to an exemplary third embodiment. The rotation angle detection system 1" of the third embodiment differs from the rotation angle detection system 1' of the second embodiment in that the rotation angle detection system 1" has a safety path sensor unit 21 as an additional sensor unit besides the resolver 20. The main electronic path of the rotation angle detection system 1" does not differ in its operating principle and configuration from the main electronic path of the rotation angle detection system 1', so reference is made to the preceding explanations regarding this. Fig. 2 is referred.

[0081] The distinction in the embodiment with regard to the safety path sensor unit 21 in conjunction with the electronic safety path relates in particular to the fact that this results in a separate, complete signal path that includes the safety path sensor unit 21. In the exemplary embodiment, the safety path sensor unit 21 is based on a different measuring principle and is designed here as a Hall sensor. Accordingly, different signal lines of the electronic safety path are also used for the control and signal feedback to the resolver 20. This is represented by a signal converter 40a" for a control signal and by a signal converter 40b" for the sensor signal feedback in the respective signal paths of the electronic safety path.Accordingly, the digital isolator 55" of the electronic safety path of the rotary angle detection system 1" may also be designed differently than the digital isolator 55 of the electronic safety path of the rotary angle detection system 1'.

[0082] Furthermore, the explanations regarding the second embodiment can be applied analogously to the third embodiment.

[0083] Fig. 4Figure 1 shows a schematic representation of a rotary angle detection system 1‴ for a rail vehicle according to an exemplary fourth embodiment. The rotary angle detection system 1‴ of the fourth embodiment differs from the rotary angle detection system 1' of the second embodiment in that the rotary angle detection system 1‴ does not have an electronic safety path with corresponding components. At least partial redundancy is achieved here with respect to a redundant design of the signal processing units 70, 80, which are connected in parallel via the digital isolator 54 to the resolver-digital converter 30. Accordingly, the rotary angle detection system 1‴ has two identical interface connections to the two signal processing units 70, 80, which also serve for control. This allows for the increased use of standard components. With failure rates of digital isolators of, for example, approximately...10 FIT does not necessarily increase the probability of failure of the overall system.

[0084] Furthermore, the explanations regarding the second embodiment can be applied analogously to the fourth embodiment. REFERENCE MARK LIST

[0085] 1, 1', 1", 1‴Rotation angle detection system 2, 2'Battery potential 3, 3'Sensor unit housing 10Motor (brake drive) 20Resolver (sensor unit) 21Safety path sensor unit (sensor unit) 30Resolver-digital converter (electronics main path) 31Excitation signal switch (electronics main path) 32Sine signal switch (electronics main path) 33Cosine signal switch (electronics main path) 40Resolver-digital converter (electronics safety path) 40a"Signal converter (electronics safety path) 40b"Signal converter (electronics safety path) 41Excitation signal switch (electronics safety path) 42Sine signal switch (electronics safety path) 43Cosine signal switch (electronics safety path) 51Excitation signal transformer 52Sine signal transformer 53 Cosine signal transformer 54 Digital insulator (electronics main path) 55,55" Digital isolator (electronics safety path) 60 Power supply 70 Signal processing unit (electronics main path) 71 Signal output switch (electronics main path) 80 Signal processing unit (electronics safety path) 81 Signal output switch (electronics safety path) 90 Motor drive control 100 Train 200 Brake actuator

Claims

1. A rotational angle detection system (1, 1', 1", 1‴) for a rotational angle detection of a rotary brake drive (10) for a rail vehicle, having: at least one sensor unit (20, 21) for detecting a rotational angle, which can be operatively connected to the rotary brake drive (10), and at least one main electronic path for the transmission of control signals and / or sensor signals, wherein the at least one main electronic path can be operatively connected to the at least one sensor unit (20, 21), characterized in that the at least one main electronic path has at least one signal transmitter (51, 52, 53, 54) which divides the main electronic path into a section of the main electronic path facing the sensor unit (20, 21) from the signal transmitter (51, 52, 53, 54) and a section of the main electronic path facing away from the sensor unit (20, 21) from the signal transmitter (51, 52, 53, 54), and wherein the at least one signal transmitter (51, 52, 53, 54) is configured to galvanically isolate the at least one sensor unit (20, 21) from the section of the main electronic path facing away from the sensor unit (20, 21).

2. The rotational angle detection system (1, 1') as claimed in claim 1, wherein the rotational angle detection system (1, 1') further has: at least one safety electronic path for the transmission of control signals and / or sensor signals, wherein the at least one safety electronic path can be operatively connected to the at least one sensor unit (20, 21), wherein the at least one safety electronic path has at least one signal transmitter (55, 55"), which divides the safety electronic path into a section of the safety electronic path facing the sensor unit (20, 21) from the signal transmitter (55, 55") and a section of the safety electronic path facing away from the sensor unit (20, 21) from signal transmitter (55, 55"), wherein the at least one signal transmitter (55, 55") is configured to galvanically isolate the at least one sensor unit (20, 21) from the section of the safety electronic path facing away from the sensor unit (20, 21).

3. The rotational angle detection system (1, 1', 1", 1‴) as claimed in claim 1 or 2, wherein the at least one sensor unit (20, 21) is arranged in a sensor unit housing (3, 3') and the at least one signal transmitter (51, 52, 53, 54, 55, 55") of the main electronic path and / or the safety electronic path forms the signal input and / or signal output of the main electronic path and / or the safety electronic path into and / or out of the sensor unit housing (3, 3').

4. The rotational angle detection system (1, 1', 1", 1‴) according to any one of the preceding claims, wherein the at least one signal transmitter (51, 52, 53, 54, 55, 55") of the main electronic path and / or the safety electronic path is a signal transformer (51, 52, 53), a digital isolator (54, 55, 55") or an optical coupler or has at least one signal transformer (51, 52, 53), a digital isolator (54, 55, 55") and / or an optical coupler.

5. The rotational angle detection system (1, 1', 1", 1‴) according to any one of the preceding claims, wherein the at least one sensor unit (20) is a resolver (20) or has at least one resolver (20).

6. The rotational angle detection system (1, 1', 1", 1‴) as claimed in claim 5, wherein the main electronic path and / or the safety electronic path has at least one resolver to digital converter (30, 40) which is specifically designed to magnetically excite a rotor of the resolver (20), preferably with an alternating voltage of constant amplitude, and to receive sine and cosine signals of a stator of the resolver (20).

7. The rotational angle detection system (1, 1', 1", 1‴) as claimed in claim 6, wherein between the resolver to digital converter (30, 40) in the main electronic path and / or in the safety electronic path and the resolver (20) at least one excitation signal switch (31, 41) is arranged for disconnecting and connecting the resolver to digital converter (30, 40) and the resolver (20) with respect to an excitation signal path in the main electronic path and / or safety electronic path, at least one sine signal switch (32, 42) for disconnecting and connecting the resolver to digital converter (30, 40) and the resolver (20) with respect to a sine signal path in the main electronic path and / or safety electronic path and / or at least one cosine signal switch (33, 43) for disconnecting and connecting the resolver to digital converter (30, 40) and the resolver (20) with respect to a cosine signal path in the main electronic path and / or safety electronic path.

8. The rotational angle detection system (1, 1', 1", 1‴) as claimed in claim 6 or 7, wherein the at least one resolver to digital converter (30, 40) and / or one signal processing unit (70, 80) is / are designed to determine a rotational angle position of the resolver (20) from the sine and cosine signals of the stator of the resolver (20), in particular taking into account a number of pole pairs of the resolver (20).

9. The rotational angle detection system (1, 1', 1", 1‴) as claimed in any one of the preceding claims, wherein the at least one resolver to digital converter (30, 40) is located in the main electronic path and / or in the safety electronic path in the section of the main electronic path or the section of the safety electronic path facing the sensor unit (20, 21).

10. The rotational angle detection system (1") as claimed in any one of claims 2 to 9, wherein the rotational angle detection system (1") comprises at least one sensor unit (20) and a safety path sensor unit (21) as a further sensor unit, wherein the at least one safety electronic path can be operatively connected to the safety sensor unit (21).

11. The rotational angle detection system (1") as claimed in claim 10, wherein the sensor unit (20) and the safety path sensor unit (21) have a mutually different measuring principle or a mutually different measuring configuration.

12. The rotational angle detection system (1, 1', 1", 1‴) as claimed in any one of the preceding claims, wherein the rotational angle detection system (1, 1', 1", 1‴) comprises at least one signal processing unit (80) in the main electronic path in the section of the main electronic path facing away from the sensor unit (20, 21) and at least one signal processing unit (70) in the safety electronic path in the section of the safety electronic path facing away from the sensor unit (20, 21).

13. The rotational angle detection system (1‴) as claimed in any one of claims 1 to 11, wherein the rotational angle detection system (1‴) comprises at least one signal processing unit (80) and at least one further signal processing unit (70) in the main electronic path in the section of the main electronic path facing away from the sensor unit (20, 21), and wherein the at least one signal processing unit (80) and the at least one further signal processing unit (70) are connected in parallel.

14. A braking system for a rail vehicle, having: at least one brake actuator (200) for applying a braking force, at least one rotary brake drive (10) for actuating the brake actuator, and at least one rotational angle detection system (1, 1', 1", 1‴) as claimed in any one of claims 1 to 13.

15. A rail vehicle with at least one rotational angle detection system (1, 1', 1", 1‴) as claimed in any one of claims 1 to 13 and / or a braking system as claimed in claim 14, wherein at least the sensor unit (20, 21) is arranged in a bogie of the rail vehicle.