WO2019048261A1

WO2019048261A1 - Brake device and method for operating a brake device

Info

Publication number: WO2019048261A1
Application number: PCT/EP2018/072880
Authority: WO
Inventors: Marcus Fischer; Thomas Hessling; Marco BRÄUNLICH
Original assignee: Knorr-Bremse Systeme für Schienenfahrzeuge GmbH
Priority date: 2017-09-05
Filing date: 2018-08-24
Publication date: 2019-03-14
Also published as: DE102017215625A1

Abstract

A brake device for a rail vehicle has at least one brake cylinder (16) and a pressure-regulating apparatus (12) for making available a regulating pressure (Pa) for the brake cylinder (16) on the basis of a supply pressure (Ps) which is made available. In order to achieve improved regulation of the braking effect, it is proposed to sense the regulating pressure (Pa) downstream of the pressure-regulating apparatus (12), to estimate a brake cylinder pressure (Pb) in the brake cylinder (16) on the basis of this sensed regulating pressure (Pa), and to actuate the pressure-regulating apparatus (12) as a function of the estimated brake cylinder pressure (Pb).

Description

DESCRIPTION

Brake device and method for operating a brake device The invention relates to a brake device and a method for operating a brake device. In particular, the invention relates to a braking device for a rail vehicle, a rail vehicle with such a braking device and a method for operating a braking device for a rail vehicle. Rail vehicles often use pneumatic or hydraulic brake systems. Such brake systems have, for example, pressure-actuated brake cylinders which can generate a braking effect when a pressure is applied. For the generated braking effect, the pressure in the brake cylinder is of great importance, which is why it is desirable or advantageous to know this brake cylinder pressure as accurately as possible. In rail vehicles, integration of components in bogies is due to environmental factors (e.g.

Temperature, humidity) but generally associated with increased effort, which is why the brake cylinder pressure is usually not measured directly. DE 10 2012 004 892 A1 describes an observer for a braking device of a rail vehicle, which can estimate based on pressure data and control data control pressure to be provided downstream of a pressure control device the brake cylinder to control the pressure control device accordingly. The pressure data supplied to the observer represent a supply pressure present upstream of the pressure control device.

Due to the conduit system between the pressure control device and the brake cylinder and the pneumatic resistance and dynamic behavior caused thereby, the control pressure provided by the pressure control device does not correspond to the actual pressure in the brake cylinder, in particular during the transient phase of the system. It is therefore an object of the present invention to provide an improved brake device and method for operating a brake device that can control the braking effect achieved by a brake cylinder.

This object is solved by the teachings of the independent claims. Particularly advantageous embodiments of the invention are specified in the dependent claims. The brake device according to the invention has at least one brake cylinder, a pressure control device for providing a control pressure for the brake cylinder, starting from a supply pressure provided and a control device for actuating the pressure control device. In addition, according to the invention, a pressure sensor for detecting the control pressure downstream of the pressure control device and an observer are provided. The observer is connected to the pressure sensor and designed such that it estimates a brake cylinder pressure in the brake cylinder on the basis of the control pressure detected by the pressure sensor. The control device is correspondingly designed such that it controls the pressure control device as a function of this estimated by the observer brake cylinder pressure.

According to the invention, it is proposed to detect the control pressure downstream of the pressure control device and to estimate the actually present brake cylinder pressure on the basis of this detected control pressure. The estimation of the brake cylinder pressure made in this way allows comparison to a mere

Control of the pressure control device based on an estimate of the control pressure provided by the pressure control device based on a detected supply pressure upstream of the pressure control device, a regulation of the pressure control device and thus the control pressure, so that the braking effect generated by the brake cylinder can also be controlled.

In conventional brake devices in particular the opening behavior and the flow behavior of the pressure control device or its valves were taken into account. That is, for example, with the help of maps of the pressure control device or their valves determines how long an opening signal must be sent to corresponding switching valves to produce a defined pressure increase in a defined volume. The brake device according to the invention, however, measures the control pressure downstream or at the output of the pressure control device to close from this to the actual brake cylinder pressure in the brake cylinder. This makes it possible to know and regulate the brake cylinder pressure during the dynamic transient phase. Thus, if necessary, a higher accuracy in the

Determination and regulation of the pressure curve can be achieved. Since the brake cylinder pressure or its time course influence on the braking effect of the brake system, in this way, the safety of the brake system can be improved.

Due to the precise knowledge of the actual pressure in the brake cylinder and environmental influences in the regulation of the pressure control device can be considered and possibly compensated. The proposed detection of the control pressure downstream of the pressure control device also enables a faster and more reliable detection of malfunctions (for example, leaks, hose breakage, etc.) in the components (especially the line system and brake cylinder) downstream of the pressure control device. Finally, the evaluation of the detected control pressure downstream of the pressure control device by the observer also allows self-calibration or continuous self-calibration of the control of the pressure control device or the entire braking device.

In the estimation of the brake cylinder pressure based on the detected control pressure, an estimation of the time profile of the brake cylinder pressure is preferably based on the detected control pressure and the detected time profile of the control pressure. In this way, the estimation of the brake cylinder pressure, in particular during a transient phase, in which usually larger pressure differences are present, can be performed more accurately. Also, the brake cylinder pressure can be determined with the solution according to the invention independently of the actual valve opening times of the pressure regulating device; Even during an opening of the pressure control device can be deduced on the brake cylinder pressure. The observer is preferably connected to the control device or integrated into it. The observer may preferably be implemented as software, hardware or a combination thereof. A control device which is designed to perform the function of the observer can also be regarded as an observer.

The control device is preferably connected to a brake actuating device for triggering (starting and preferably also setting a braking level, in predetermined stages or continuously) of a braking operation in order to control the pressure regulating device in response to an actuation of this brake actuating device.

In an advantageous embodiment of the invention, the observer is designed such that he estimates the brake cylinder pressure based on a model of components (esp., For example, line system and possibly also brake cylinder) of the braking device downstream of the pressure control device. The model is preferably in

Observer deposited.

The model preferably represents a transfer function of the control pressure provided by the pressure regulating device to the brake cylinder pressure, particularly preferably a chronological progression of the transfer function of the control pressure provided by the pressure regulating device to the brake cylinder pressure. The transfer function mentioned here relates in particular to the pneumatic transfer behavior. The model is preferably a project-specific model which is determined in a design phase of the respective braking device for a project and / or regularly, empirically and / or experimentally and / or which can be automatically calibrated during operation of the braking device. In an advantageous embodiment of the invention, the braking device further comprises at least one further pressure sensor for detecting the supply pressure upstream of the pressure regulating device and / or at least one further pressure sensor for detecting a pressure generated within the pressure regulating device. In In this case, the control device is preferably also connected to the at least one further pressure sensor in order to control the pressure control device as a function of the pressure detected by the at least one further pressure sensor. Preferably, these other print data for this purpose also from

Observers are used. By taking into account not only the control pressure downstream of the pressure control device but also the supply pressure upstream of the pressure control device and / or the pressure generated within the pressure control device, the control or regulation of the braking device can be further optimized.

The invention also relates to a rail vehicle having at least one braking device of the invention described above, or the use of the braking device described above in a rail vehicle. As a rail vehicle in this context, all types of cars with or without their own drive and firmly coupled units of several such cars are called. An association of rail vehicles is commonly referred to as train and is formed by variable coupling of multiple rail vehicles. The inventive method for operating a brake device with at least one brake cylinder, wherein a pressure control device provides a control pressure for the brake cylinder based on a provided supply pressure, according to the invention, the steps of detecting the control pressure downstream of the pressure control device, the estimation of a brake cylinder pressure in the brake cylinder on the basis of detected control pressure and the driving of the pressure control device in dependence on the estimated brake cylinder pressure. The driving of the pressure control device should preferably also include a control in dependence on an estimated time profile of the brake cylinder pressure.

With this method of the invention, the same advantages can be achieved, which are explained above in connection with the braking device according to the invention. With regard to the advantages, the definitions of terms and the preferred embodiments, reference is therefore additionally made to the above statements.

In an advantageous embodiment of the invention, the brake cylinder pressure is estimated based on a model of components of the brake device downstream of the pressure control device. The model used preferably represents a transfer function of the control pressure provided by the pressure control device to the brake cylinder pressure. In addition, the model is preferably a project-specific model, which is determined in a design phase of the braking device for a project and / or regularly, empirically and / or experimentally and / or that is automatically calibrated during operation of the brake device.

In an advantageous embodiment of the invention can also be carried out based on the detected control pressure error checking of components of the braking device downstream of the pressure control device. Thus, for example, a leak in the brake cylinder or in the line system to the brake cylinder can be detected quickly and reliably from the detected control pressure or the detected time profile of the control pressure. This error detection is possible in advance already during the regulation of the pressure control device and not only after the end of the control and the then detectable pressure drop.

In a further advantageous embodiment of the invention, an (automatic) self-calibration of the control of the pressure control device or of the brake device can be carried out on the basis of the detected control pressure.

In a still further advantageous embodiment of the invention, the supply pressure upstream of the pressure regulating device and / or at least one pressure generated within the pressure regulating device are also detected. In this case, the pressure regulating device is preferably dependent on the detected

Supply pressure and / or pressure controlled. The above and other advantages, features and applications of the invention will become more apparent from the following description of an embodiment with reference to the accompanying drawings. In the drawings: FIG. 1 shows the basic structure of a braking device for a rail vehicle according to the present invention;

Fig. 2 pressure / time diagrams to illustrate the operation of the

Braking device of the present invention; and

Fig. 3 shows the structure of a braking device for a rail vehicle according to a

Embodiment of the invention.

Fig. 1 illustrates the basic structure of a braking device for a rail vehicle according to the invention.

The braking device is connected to a pressure reservoir 10, for example in the form of a compressed air reservoir or a compressed air line, which provides a supply pressure Ps. This supply pressure Ps is made available to a pressure regulator 12, which provides a control pressure Pa on the output side. This control pressure Pa is then fed via a line system 14 at least one brake cylinder 16. In the brake cylinder 16 is a brake cylinder pressure Pb, with the aid of a braking effect is generated. The braking device also has a control device 18. This control device 18 controls the pressure control device 12.

FIG. 2 shows the transmission or temporal behavior of the transmission of the control pressure Pa provided by the pressure control device 12 to the brake cylinder pressure Pb. As can be seen from the two pressure / time diagrams, a pressure difference between the control pressure Pa and the brake cylinder pressure Pb is especially during a transient phase after the triggering of a braking operation and the corresponding control of the pressure control device 12 by the control device 18 available. Only after completion of the pressure equalization does the brake cylinder pressure Pb substantially correspond to the control pressure Pa.

In order to efficiently control the braking effect generated by the brake cylinder 16, the brake cylinder pressure Pb or its time profile is taken into account by the control device 18 in order to regulate the pressure control device 12 accordingly. On a direct measurement of the pressure in the brake cylinder 16 should be waived.

An observer 20 is therefore integrated in the control device 18. In other embodiments of the invention, the observer 20 is a separate component which is connected to the control device 18, or the control device 18 itself also assumes the function of the observer 20.

The observer 20 is connected to a pressure sensor 22, which detects the control pressure Pa downstream of the pressure control device 12, for example, directly at the output of

Pressure control device 12 or at a distance to this in the line system 14 to the brake cylinder sixteenth

In the observer 20, a project-specific model M is deposited, which has been empirically and / or experimentally determined / determined, for example, during the design phase of the braking device. Alternatively or additionally, the model M can also be determined / determined on a regular basis (for example when starting up the braking device). This model M takes into account in particular the components of the braking device downstream of the pressure regulating device 12, i. the conduit system 14 and possibly also the at least one brake cylinder 16 itself. Here, the model M represents the

Transfer function or the time course of the transfer function of the control pressure Pa provided by the pressure control device 12 to the brake cylinder pressure Pb. Preferably, this model M is also calibrated automatically during operation of the brake device.

Since the control pressure Pa downstream of the pressure control device 12 is detected and evaluated, the actual brake cylinder pressure Pb in the brake cylinder 16 by means of the model M by the observer 20 can be estimated relatively accurately. It can be Thus, achieve a regulation of the pressure control device 12 and the entire braking device, so that a more efficient control of the braking effect achieved by the brake cylinder 16 can be achieved. Other advantages of the detection of the control pressure Pa downstream of the pressure control device 12 are the possibilities of error checking the components 14, 16 of the braking device downstream of the pressure control device 12, a consideration of environmental influences on the brake cylinder pressure Pb and a self-calibration or continuous self-calibration of the control of the pressure control device 12 or the braking device ,

Fig. 3 shows an embodiment of a braking device of the invention in more detail. Compared to the basic structure of Fig. 1, a brake actuator 24 is shown, which is connected to the control device 18. About this brake confirmation 24 can - for example, manually by a vehicle driver or automatically by an automated vehicle control system or safety system - a braking operation are triggered. Preferably, the brake-actuating device 24 is configured so that a braking operation can be started and also (in predetermined stages or steplessly) a desired braking level can be set. The control device 18 accordingly controls the pressure control device 12 as a function of an actuation of this brake control device 24.

The pressure control device 12 used in the brake device according to the invention is not limited to any specific embodiments. For example, the pressure regulator 12 may include a pressure regulator 28 that generates a pressure Pr based on the supply pressure Ps provided by the pressure reservoir 10, which pressure is used to drive valves (eg, relay valves, etc.) in the pressure regulator 12. As shown in FIG. 3, further pressure sensors 26, 30 may optionally be provided. These further pressure sensors 26, 30 detect, for example, the supply pressure Ps provided upstream of the pressure control device 12 or one or more pressures Pr generated within the pressure control device 12. These detected pressure data Pr, Ps of the further pressure sensors 26, 30 are also transmitted to the control device 18 fed.

In this way, the control device 18, the pressure control device 12 in response to these other print data Pr, Ps control or can

Observer 20 also use these other print data Pr, Ps. By taking into account not only the control pressure Pa downstream of the pressure regulator 12 but also the pressure data Pr, Ps upstream or inside the pressure regulator 12, the control of the brake device can be further optimized.

LIST OF REFERENCE NUMBERS

10 pressure reservoir

12 pressure control device

14 pipe system

16 brake cylinders

18 control device

20 observers

22 pressure sensor

24 brake actuator

26 additional pressure sensor

28 pressure regulator

30 more pressure sensor M model

Pa control pressure = outlet pressure of the pressure regulator

Pb brake cylinder pressure in the brake cylinder

Pr pressure within the pressure regulator

Ps supply pressure of the pressure reservoir

Claims

1. Braking device, in particular for a rail vehicle, comprising:

at least one brake cylinder (16);

a pressure control device (12) for providing a control pressure (Pa) for the brake cylinder (16) based on a provided supply pressure (Ps); and a control device (18) for activating the pressure control device (12), characterized in that

a pressure sensor (22) for detecting the control pressure (Pa) is provided downstream of the pressure regulator (12);

an observer (20) is provided which is connected to the pressure sensor (22) and is configured to estimate a brake cylinder pressure (Pb) in the brake cylinder (16) based on the control pressure (Pa) detected by the pressure sensor (22); and

the control device (18) is designed to control the pressure control device (12) as a function of the brake cylinder pressure (Pb) estimated by the observer (20).

2. Braking device according to claim 1, wherein

the observer (20) is configured to estimate the brake cylinder pressure (Pb) based on a model (M) of components (14,16) of the brake device downstream of the pressure regulator (12).

3. Braking device according to claim 2, wherein

the model (M) represents a transfer function of the control pressure (Pa) provided by the pressure control device (12) to the brake cylinder pressure (Pb).

4. Braking device according to claim 2 or 3, wherein

the model (M) is a project-specific model that is used in a design phase of the braking device for a project and / or regularly, empirically and / or

can be determined experimentally and / or automatically calibrated during operation of the brake device.

5. Braking device according to one of claims 1 to 4, wherein

at least one further pressure sensor (26) for detecting the supply pressure

(Ps) are provided upstream of the pressure regulating device (12) and / or at least one further pressure sensor (30) is provided for detecting a pressure (Pr) generated within the pressure regulating device (12); and

the control device (20) is connected to the at least one further pressure sensor (26, 30) and is configured to control the pressure control device (12) as a function of the pressure detected by the at least one further pressure sensor (26, 30)

Supply pressure (Ps) and / or pressure (Pr) to control.

6. Use of the braking device according to one of claims 1 to 5 in a rail vehicle.

7. A method for operating a brake device, in particular a brake device for a rail vehicle, with at least one brake cylinder (16), wherein a pressure control device (12) starting from a provided supply pressure (Ps) provides a control pressure (Pa) for the brake cylinder (6),

characterized in that

the control pressure (Pa) is detected downstream of the pressure control device (12);

on the basis of the detected control pressure (Pa) a brake cylinder pressure (Pb) in the brake cylinder (16) is estimated; and

the pressure regulating device (12) is activated as a function of the estimated brake cylinder pressure (Pb).

8. The method of claim 7, wherein

the brake cylinder pressure (Pb) is estimated based on a model (M) of components (14,16) of the brake device downstream of the pressure regulator (12).

9. The method of claim 8, wherein

10. The method of claim 8 or 9, wherein

determined experimentally and / or automatically calibrated during operation of the braking device.

1 1. A method according to any one of claims 7 to 10, wherein

based on the detected control pressure (Pa) an error check of components (14, 16) of the brake device downstream of the pressure control device (12) is performed.

12. The method according to any one of claims 7 to 11, wherein

based on the detected control pressure (Pa), a self-calibration of the control of the pressure control device (12) or the brake device is performed.

13. The method according to any one of claims 7 to 12, wherein

the supply pressure (Ps) upstream of the pressure regulating device (12) and / or at least one pressure (Pr) generated within the pressure regulating device (12) are detected; and

the pressure control device (12) in dependence on the detected

Supply pressure (Ps) and / or pressure (Pr) is controlled.