Brake system comprising energy supply system with a combination of energy storage device types for operating at least partially electrically operated friction brake controllers for rail vehicles

Abstract

The invention relates to a brake system (B) comprising an energy supply system (4) which has a first energy storage device (5) and a second energy storage device (6). The first energy storage device (5) is designed to output a defined energy quantity in order to maintain a safety brake function, thereby completely actuating a brake force unit within a first time window (t1). The second energy storage device (6) is designed to output an energy quantity over a second time window (t2), wherein the second time window (t2) is greater than the first time window (t2). The first energy storage device (5) has, as the design goal, an output per time unit which is as high as possible for the output request. The second energy storage device (6) has the goal of maintaining the availability of the safety brake function over an operating duration which is as long as possible in the event the external energy supply is interrupted even if no brake energy is present, or brake energy is to be provided only to a minimal extent in order to supply an electronic standby unit.

Description

[0001] DESCRIPTION

[0002] Braking system with energy supply system with combined energy storage types for operating at least partially electrically operated friction brake actuators in rail vehicles

[0003] The use of at least partially electrically operated friction brake actuators, the so-called electro-mechanical brakes, is becoming an increasingly advantageous alternative to pneumatic braking systems in rail vehicles.

[0004] Document DE102017 215 289 A1 discloses a brake actuator for a rail vehicle having a housing, a pressing part configured to be pressed against a brake disc, a means for moving the pressing part, a logic unit in or on the housing configured to control the means for moving the pressing part, a control connection on the housing, a supply connection on the housing for supplying the brake actuator with energy, and power electronics with energy storage arranged in or on the housing and assigned only to the one brake actuator.

[0005] Pneumatic braking systems and electromechanical brakes, on the other hand, usually contain mechanical components for actuating disc and wheel brakes. Pneumatic braking systems are now considered a highly reliable technology due to their historical and technically established reliability, based on the experience gained over a very long period of time (approximately 150 years). This pneumatic friction brake approach provides a highly available and permanent braking capability, which is also independent of the condition of other systems or environmental influences on the vehicle. It is therefore prescribed in all markets worldwide by standards and norms as a requirement for rail vehicles in the mainline sector. In addition, braking systems exist that are based on other technological approaches, such as:The electrodynamic brake, which utilizes the physical effect of induction to recover kinetic energy through braking, is thus more economical. However, such a brake is considered to be not highly available and functionally unsafe, as the dissipation of braking energy and its functionality generally depend on the condition of the involved electrical and, in some cases, electronic subsystems, as well as the condition of the vehicle.

[0006] This also applies to electro-mechanical braking systems.

[0007] It is therefore an object of the present invention to provide an alternative friction brake system based on an electro-mechanical operating principle with an associated safe energy supply.

[0008] This object is achieved by a braking system according to claim 1. Further advantageous embodiments of the present invention are the subject of the dependent claims.

[0009] A braking system according to the invention is designed to generate at least one friction braking force with or as a result of a safety braking function (e.g. for rapid braking or emergency braking).

[0010] A safety braking function is a local or train-wide function of the braking system that has increased safety requirements—for example, an emergency brake or a parking brake. A corresponding safety braking path is a sequence of functions that, as a whole, implement a braking process with high safety integrity.

[0011] A braking system according to the invention comprises at least one at least partially electrically operated friction brake actuator. An electromechanical braking system is a braking system that provides the ability to generate a deceleration force or braking force of a vehicle using at least electronic, electrical, and mechanical components.

[0012] Furthermore, the braking system according to the invention includes at least one

[0013] Brake control unit configured to provide at least one control or control signal for a force control variable (e.g., application force, braking torque). A force control variable is a control or regulating variable that either directly or indirectly represents a requirement of the braking path to generate a force in a coordinate system relevant to the brake actuator (e.g., cylinder force), as well as to take into account associated control or manipulation variables such as reduction signals, adjustment variables for quality improvement, etc. when setting this force.

[0014] The brake control unit is also a conglomerate of functions for providing train-wide and local braking and extension functions in the braking path based on control inputs and / or vehicle state variables and / or braking state variables. A braking path is the sum of all functions that are active between the control inputs of the braking system and the generation of the friction braking force and that establish the system-wide braking functions.

[0015] Furthermore, a braking system according to the invention includes at least one actuator control unit configured to provide at least one actuation variable as a control or actuating signal (e.g., an excitation variable for the principle of an electric machine) for at least one braking force unit. The actuator control unit includes, for example, a conglomerate of functions for providing motor vehicles in the braking path based on force actuating variables.

[0016] The actuator control unit receives control inputs from the brake control unit with the aim of implementing the force control variable via a safe control path as part of the safety braking functions. Furthermore, a switchover to a state can occur in which the brake force unit is placed in a safe state.

[0017] Furthermore, the braking system includes at least one braking force unit which is configured to convert an actuating force into a friction braking force for converting the at least one actuation variable received from the actuator control unit as control or actuating signals.

[0018] The braking force unit, for example, contains a conglomerate of functions for generating a friction braking force based on actuation variables. An actuation variable is a control or regulating variable that must necessarily be provided for the electromechanical process in question or its operating principle in order to define and request a unique motion state, force state, position state, or similar state properties (e.g., parking brake).

[0019] A braking system according to the invention further comprises an energy supply system which is configured to supply the at least one braking force unit with energy, and the energy supply system has at least a first energy store and a second energy store. The first energy store is configured to deliver a defined amount of energy with a defined mechanical or electrical maximum power to maintain at least one safety braking function with at least one complete actuation of the braking force unit within a first time period. The second energy store, in contrast, is configured to deliver an amount of energy over a second time period, wherein the second time period is greater than the first time period. The design objective of the first energy store is to enable the highest possible power for the power demand per unit of time and at least over the duration of the actuation (e.g.until a braking force unit reaches the safe state during emergency braking). For the second energy storage device, however, a lower energy demand per unit of time is required, with the aim of maintaining the availability of the safety braking function in the event of an interruption in the external energy supply for as long an operating period as possible, even if no braking energy is available or only a minimal amount of braking energy needs to be made available to supply standby electronics. Furthermore, the second energy storage device must be designed to provide a switchover process to the first energy storage device for exercising at least one safety braking function with at least one complete actuation function over as long an operating period as possible.

[0020] The associated energy supply is provided at least partially with a safety integrity, with the aim of providing, together with the braking force unit and its function for safe braking force generation, a safe friction braking force on demand to fulfill the safety braking functions.

[0021] The first energy storage unit and the second energy storage unit are therefore a buffer storage unit - the first energy storage unit can provide maximum energy even over a short period of time, while the second energy storage unit can provide a constant energy supply, but over the longest possible period of time.

[0022] The brake control unit provides the control or actuating signal for a force control variable, preferably using software-based safety braking functions. The actuator control unit is designed to implement the force control variable using a safety control path as part of the safety braking function. Optionally, a switching command can also be generated to place the brake force unit in a safe state. The power supply system ensures that emergency braking or rapid braking can be initiated quickly, even with an electromechanical braking system.

[0023] Thus, the advantages of pneumatic braking systems can also be implemented in electromechanical braking systems. For example, the system weight can be reduced because additional peripheral systems for energy conversion, such as a compressor, which is necessary with a pneumatic braking system, are not required. Braking system functions can be provided using electronics and software methods, and functions can be provided depending on customer requests, market requirements, and vehicle types. Furthermore, situation-dependent dynamic behavior during the system's operating time is possible thanks to electronics and software, which also leads to improved braking quality, for example, braking distance and braking comfort. Furthermore, the dynamics of the braking force variation or the change in state of the brake can be increased to improve braking quality, for example with an anti-skid function.

[0024] Maintenance and fault detection are therefore easier, and the braking system can also be integrated into driver assistance models. The first and / or second energy storage units can each include multiple redundant energy storage units. This allows energy to be provided with a high degree of safety and availability.

[0025] Preferably, the braking system is further adapted to generate a friction braking force with a service braking function.

[0026] Service braking functions are local or train-wide braking functions of the braking system that have a standard safety requirement. A corresponding service braking path is a sequence of functions that, as a whole, implement a braking process with low safety integrity. The braking system according to the invention therefore allows for rapid switching between safety braking functions (i.e., emergency or rapid braking) and service braking functions.

[0027] Preferably, the energy supply system is configured to also supply the actuator control unit and the brake control unit with energy, and in particular the second energy store is configured to supply the actuator control unit and the brake control unit with energy, optionally additionally the brake force unit.

[0028] Thus, different parts of the energy supply system supply different components of the braking system, which in turn leads to high safety integrity.

[0029] Preferably, the first or second energy storage device is configured to store electrical energy. In this case, the first energy storage device can advantageously be an electrical storage device with highly capacitive properties, preferably a capacitor, more preferably a plate capacitor or supercapacitor, and the second energy storage device is preferably a chemical storage device, more preferably an accumulator. A plate capacitor or supercapacitor enables the rapid release of large amounts of energy, while an accumulator enables the release of a smaller amount of energy, albeit over a very long period of time.

[0030] Alternatively, the first energy storage device and / or the second energy storage device are configured to store pneumatic, chemical, hydraulic, or mechanical energy. In this case, the energy supply system preferably has a charging unit for the at least first and / or second energy storage device, which is adapted to convert supplied electrical energy into an energy form compatible with the first and / or second energy storage device.

[0031] Both energy storage units can be powered by electrical energy, but energy can also be stored in other forms.

[0032] Preferably, the first energy storage device is adapted to charge the second energy storage device, and / or the second energy storage device is adapted to charge the first energy storage device.

[0033] Further preferably, the braking system according to the invention further comprises an electrical interface which is adapted to supply the energy supply system with external electrical energy.

[0034] This means that the first energy storage unit and / or the second energy storage unit can be recharged accordingly if they do not have enough energy stored.

[0035] Further preferably, the braking system comprises a supply monitor and a switching unit, wherein the supply monitor is configured to evaluate the status and integrity of the storage devices contained in the energy supply system as well as the electrical interface, and optionally to generate at least one switching command.

[0036] The switching unit, on the other hand, is adapted to receive and execute at least one switching command, thus switching the supply of at least the brake force unit and optionally the actuator control unit, and further optionally the brake control unit of the braking system, to one of the two energy storage devices or the electrical interface. This can serve, for example, as a protective mechanism (e.g., in the event of faulty energy or power being supplied from a storage device).

[0037] Further preferably, the energy supply system further comprises an energy supply unit that can provide electrical energy to the first and second energy storage devices, as well as to the braking force unit, the actuator control unit, and / or the brake control unit. The electrical energy is available through movement of the braking force unit or energy harvesting from preferably other components, further preferably in the form of a piezoelectric effect, a thermoelectric effect, and / or a photoelectric effect, or simply energy generated by a generator.

[0038] Furthermore, the braking force unit is preferably adapted to assume a safe state with the aid of a function for safe braking force generation or maintenance, which can be maintained with the aid of a locking function even without further energy supply. The function for safe braking force generation or maintenance is extremely important, especially in the case of a rapid braking function or emergency braking function.

[0039] In the following, embodiments of the present invention are described in more detail with the aid of the accompanying figures.

[0040] Fig. 1 shows a schematic diagram of a braking system according to the present invention.

[0041] Fig. 2 shows a schematic diagram of a first detailed embodiment of the present invention.

[0042] Fig. 3 shows a detailed diagram of a second embodiment of the present invention. Fig. 1 shows the braking system B according to the invention. This includes a brake control unit 1, which receives a switching command and outputs force control variables, an actuator control unit 2, which receives force control variables and outputs actuator variables, and a braking force unit 3, which receives actuation variables and energy from outside. The entire braking system B, in turn, outputs braking forces. Fig. 1 shows logical units, which in one embodiment can all be accommodated on separate functional carriers (e.g. control units), but in another embodiment can all be accommodated on a single functional carrier. These can be hardware units, software units, or combined units.

[0043] The energy supply system 4 of the braking system has an external energy supply via an electrical interface 8, and it includes a buffer storage unit 12, which has a first energy storage unit 5 and a second energy storage unit 6. Furthermore, the energy supply system 4 includes a supply monitor 9 and a switching unit 10, as well as a charging unit 7 and an energy supply unit 11. The energy supply system 4 is capable of supplying energy to the entire braking system and of transmitting a corresponding switching command to the brake control unit 1.

[0044] Fig. 2 shows a first detailed embodiment of the present invention. The energy supply system 4, in turn, includes the buffer storage unit 12, which has a first energy storage device 5 and a second energy storage device 6. The energy supply system 4 also includes the supply monitor 9 and the switching unit 10, as well as a corresponding charging unit (7 and 7') for each storage device (5, 6). A switching command and corresponding energy supply are forwarded from the energy supply system 4 to further components of the braking system B. A first brake control unit 1 and a first actuator control unit 2 are provided, for example, in a car or car body, or at least once per bogie. The first brake control unit 1 includes service brake functions and at least one force control variable (e.g., target cylinder forces or a reduction signal) for the corresponding first actuator control unit 2.In this case, for example, a first actuator control unit 2 is provided for providing actuation variables and the service braking path. It is not relevant where exactly the first actuator control unit 2 is provided—it can also be provided directly in the actuator.

[0045] Furthermore, a second brake control unit 1', a second actuator control unit 2', and the brake force unit 3 are housed in the bogie, close to the friction force generation unit. Corresponding safety braking functions are implemented here. The second brake control unit 2' provides force control variables and at least one switching command in a safety braking path. The second actuator control unit 2' receives the force control variables and provides actuation variables in the safety braking path; this is a safe control path. The brake force unit 3 receives actuation variables via the safe control path and converts them into an actuating force using an at least partially electrical operating principle. With the aid of a locking function, the generated braking force can be maintained without energy using the actuating force energy.

[0046] The energy supply device 4 is also provided, for example, in the car or car body, but at least per bogie, per car, per car group, or per vehicle, for example, inside a car body or underfloor. The braking force unit 3, as well as the second brake control unit T, the second brake control unit 2', and other associated units are supplied with energy solely by the energy supply unit. The first energy storage device 5 is designed here as an electrical or electrochemical element, for example as a plate capacitor or supercap. The second energy storage device 6 is also designed as an electrical or electrochemical element, but here, for example, as an accumulator. The first energy storage device 5 and the second energy storage device 6 are parts of an electrical circuit arrangement that are combined to form a buffer storage unit 12.Thus, hybrid properties are present: the first energy storage device can enable high power requirements with a short operating time, and the second energy storage device 6 can enable low power requirements and high energy content with a long operating time. The charging unit 7 for the first energy storage device 5 and the charging unit 7' for the energy storage device 6 are installed as part of the energy generation unit 4. The energy for charging can come from three sources: the external power supply, the other energy storage device (first energy storage device 5 or second energy storage device 6), or the energy generation unit 4. In the braking force unit 3, the actuating force generated for the "generate safe braking force" function is generated using an electrical or electromechanical operating principle.

[0047] Fig. 3 shows the second embodiment. Again, at least one brake control unit 1 and a corresponding actuator control unit 2 are provided. These are implemented in the car or car body, or at least once per car or once per bogie. The first brake control unit 1 contains service brake functions and at least one force control variable (e.g., target cylinder force or a reduction signal) for provision to the actuator control unit 2. The actuator control unit 2 provides actuation variables for the service brake path.

[0048] Further components are located in the bogie, close to the friction force generation. A second brake control unit T is provided here, which is intended to provide force control variables and at least one switching command in the safety braking path.

[0049] Furthermore, a second actuator control unit 2' is provided, which receives the force control variables and provides actuation variables in the safety braking path. A second energy supply system 4' is also provided here, which provides a first energy storage unit 5' in the buffer storage unit 12'. This energy storage unit is designed to provide mechanical, hydraulic, or pneumatic energy. In the event of a supply error or failure in the energy supply, the switching unit 9' transfers the mechanical energy and power to the function for safe braking force generation as part of the braking force unit. Furthermore, a charging unit 1T is provided, which converts electrical energy provided by the external energy supply into the energy form of the first energy storage unit 5'. The braking force unit 3 can be used as a charging unit to provide charging energy for the first storage unit 5'.The braking force unit T contains actuation variables depending on the active braking path and implements this depending on the switching command. A further first energy supply unit 4 is provided for each car or car body, possibly also per bogie, per car, per car group, or per vehicle. The first energy supply unit 4 has the special feature that the second energy storage unit 6 is implemented for this unit and is designed as an electrical or electrochemical element, for example as an accumulator. A corresponding charging unit 7 is provided for the energy storage unit 6. This energy supply unit 4 supplies the second brake control unit 1', the second actuator control unit 2', and the braking force unit 3 with energy. The second energy supply unit 4' is also supplied with energy.The second energy storage unit 6' with the second energy supply unit 4' is thus charged by both the first energy supply unit 4 and the braking force unit 3. This makes it possible for energy to be provided by both energy supply units 4 and 4' for the safe generation of braking force, and for the safety braking function and the safe control path in the second brake control unit 1' and the actuator control unit 2' to be supplied only by the first energy supply unit 4.

[0050] The present invention relates to a braking system B with an energy supply system 4, which has at least a first energy storage device 5 and a second energy storage device 6. The first energy storage device 5 is designed to deliver a defined amount of energy with a defined mechanical or electrical maximum power to maintain at least one safety braking function with at least one complete actuation of a braking force unit 3 within a first time period t1. The second energy storage device 6, in contrast, is designed to deliver an amount of energy over a second time period t2, wherein the second time period t2 is greater than the first time period t1. The design objective of the first energy storage device 5 is to enable the highest possible power for the power call per unit of time and at least over the duration of the actuation (e.g., until the safe state of a braking force unit is reached during emergency braking).For the second energy storage device 6, however, only a lower energy demand per unit of time is necessary, with the aim of maintaining the availability of the safety braking function over the longest possible operating period in the event of an interruption of the external energy supply, even if no braking energy is available or braking energy only needs to be made available to a minimal extent to supply standby electronics.

[0051] LIST OF REFERENCE SYMBOLS

[0052] B braking system

[0053] R Friction brake actuator

[0054] 1 brake control unit

[0055] 2 Actuator control unit

[0056] 3 Brake force unit

[0057] 4 Energy supply system

[0058] 5 first energy storage

[0059] 6 second energy storage

[0060] 7, 7' loading unit

[0061] 8 electrical interface

[0062] 9 Supply monitor

[0063] 10 Switching unit

[0064] 11 Power generation unit

[0065] 12 Buffer storage unit t1 first time period t2 second time period

Claims

PATENT CLAIMS 1. Braking system (B) for a rail-bound vehicle, which is designed to generate at least one friction braking force with or as a result of a safety braking function, wherein the braking system (B) comprises: at least one at least partially electrically operated friction brake actuator (R), at least one brake control unit (1) which is designed to provide at least one control or actuating signal of a force control variable, at least one actuator control unit (2) which is designed to provide at least one actuation variable as a control or actuating signal of a force control variable for at least one braking force unit, wherein the actuator control unit (2) is adapted to receive information from the brake control unit (1), at least one braking force unit (3) which is designed toan actuating force for converting the at least one actuation variable received from the actuator control unit (2) as a control or actuating signal into a friction braking force, an energy supply system (4) which is configured to supply the at least one braking force unit (3) with energy, wherein the energy supply system (4) has at least one first energy store (5) and at least one second energy store (6), wherein the first energy store (5) is configured to deliver a defined amount of energy with a defined mechanical or electrical maximum power to maintain at least one safety braking function with at least one complete actuation of the at least one braking force unit (3) within a first time period (t1), and wherein the second energy store (6) is configured to deliver an amount of energy over a second time period (t2),where the second time period (t2) is greater than the first time period (t1)., 2. Braking system (B) according to claim 1, which is further adapted to generate a friction braking force with service braking functions.

3. Braking system (B) according to claim 1 or 2, wherein the energy supply system (4) is configured to also supply the actuator control unit (2) and the brake control unit (3) with energy, wherein the second energy store (6) is configured to supply the actuator control unit (2) and the brake control unit (1) with energy, and optionally additionally the braking force unit (3).

4. Braking system (B) according to one of the preceding claims, wherein the first energy store (5) and / or the second energy store (6) is / are designed to store electrical energy, wherein the first energy store (5) is designed as an electrical store with high capacitive properties, preferably a capacitor, more preferably as a plate capacitor or super-cap, and / or the second energy store (6) is designed as a chemical store, preferably an accumulator.

5. Braking system (B) according to one of claims 1 to 3, wherein the first energy store (5) and / or the second energy store (6) is / are configured to store pneumatic, chemical, hydraulic or mechanical energy, and / or wherein the energy supply system (4) has a charging unit (7) for at least the first (5) and / or second (6) energy store, which charging unit is adapted to convert supplied electrical energy into an energy form compatible with the first (5) and / or second (6) energy store.

6. Braking system (B) according to claim 5, wherein the first energy store (5) is adapted to charge the second energy store (6), and / or wherein the second energy store (6) is adapted to charge the first energy store (5).

7. Braking system (B) according to one of the preceding claims, further comprising an electrical interface (8) adapted to supply the energy supply system (4) with external electrical energy.

8. Braking system (B) according to claim 7, further comprising a supply monitor (9) and a switching unit (10), wherein the supply monitor (9) is configured to evaluate the status and integrity of the storage devices (5, 6) present in the energy supply system (4) and of the electrical interface (8) and to generate at least one switching command, and the switching unit (10) is adapted to receive at least one switching command and to switch the supply from at least the braking force unit (3) and optionally the actuator control unit (2) and optionally the brake control unit (1) of the braking system to one of the two energy storage devices (5, 6) or the electrical interface (8).

9. Braking system (B) according to one of the preceding claims, wherein the energy supply system (4) further comprises an energy generation unit (11) which is adapted to provide the first and second energy storage devices (5, 6) as well as the braking force unit (3), the actuator control unit (2) and / or the braking control unit (1) with electrical energy which can be generated by: movement of the braking force unit (3) or energy harvesting in the form of a piezoelectric effect, a thermoelectric effect and / or a photoelectric effect or generator-generated energy.

10. Braking system (B) according to one of the preceding claims 8 or 9, wherein the braking force unit (3) is adapted to assume a safe state with the aid of a function for safe braking force generation-maintenance, which can be maintained with the aid of a locking function even without further supply of energy.

11. Braking system (B) according to one of the preceding claims, wherein the first energy storage device (5, 5') is adapted to provide mechanical, hydraulic or pneumatic energy, and the second energy storage device (6, 6') is adapted to provide electrical energy.

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