Method for releasing an electromechanical brake, portable energy storage device for releasing an electromechanical brake, and system of a portable energy storage device and a train braking system

Abstract

A method and portable energy storage device (2) for releasing electromechanical brakes, as well as a system (1) of the portable energy storage device (2) and a train braking system (3) are disclosed. The brakes are released by respective assigned electromechanical brake actuators (4), the method including the steps of sequentially connecting the brake actuators (4) to the portable energy storage device (2) that provides electrical energy for releasing the brakes, and releasing the brakes by operating the brake actuators (4) using energy from the portable energy storage device (2).

Description

Technical Field

[0001] The present invention relates to a method for releasing an electromechanical brake, a portable energy storage device for supplying in particular an electromechanical brake actuator for releasing an electromechanical brake, and a system of a portable energy storage device and a train brake system for releasing an electromechanical brake of a brake system particularly when the power supply of a train fails.

[0002] To apply the brake, the electromechanical brake comprises an electromechanical brake actuator having a motor, sensors and electronics for enabling the supply of braking force. Since the electromechanical brake actuator is used, when the power supply of the train fails, when the brake is actuated, it will be locked and cannot be released. This is because internal components such as motors and electronics do not function without electricity.

[0003] However, in a rescue situation where, for example, a train is towed by a rescue train, the brake should be released.

[0004] One option for releasing the brake is to remove the actuators one by one from the individual brakes, but since a train can include a large number of brakes, this requires a great deal of effort. Another option is to supply energy to the brake system to release all the actuators simultaneously, but this requires a large amount of energy with a high peak current to be supplied to the system, resulting in the need for a large and heavy energy storage device and complex wiring of the train vehicles.

[0005] Therefore, the underlying object of the present invention is to provide a suitable possibility for releasing an electromechanical brake when the power supply of a train fails without increasing the mass and cost of the train and the effort for releasing the brake.

[0006] The object is achieved by a method according to claim 1, a portable energy storage device according to claim 7, a system according to claim 13 and a computer program product according to claim 15. Advantageous further developments are contained in the respective dependent claims.

[0007] According to one aspect of the present invention, a method for releasing electromechanical brakes by respective assigned electromechanical brake actuators includes sequentially connecting the brake actuators to a portable energy storage device that provides electrical energy for releasing the brakes, and releasing the brakes by operating the brake actuators using energy from the portable energy storage device.

[0008] When a portable energy storage device is used to release the brakes, there is no need to remove the actuator, and the only additional equipment on the train is a connector device for connecting the portable energy storage device to the actuator, eliminating the need to complicate the wiring on the vehicle or add a large energy storage device to the train.

[0009] In an advantageous embodiment of the method, the brake actuator is operated according to a speed profile empirically determined to minimize the total energy consumption of the brake actuator during the brake release time to enable energy-saving release of the brake.

[0010] By this means the actuator is operated according to a speed profile that consumes the least energy, thus reducing the amount of energy required and therefore the charge capacity of the energy storage device, allowing the energy storage device to be made smaller and lighter.

[0011] In a further advantageous embodiment of the method, the brake actuators are grouped into a plurality of brake actuator groups, which are supplied sequentially and individually by the portable energy storage device.

[0012] Since the number of brake actuators to be operated to simultaneously release the brakes is reduced by this means, the energy required simultaneously to release the brakes is reduced. Accordingly, the charging capacity of the portable energy storage device can also be reduced, and as a result, the cost is reduced, the size and weight are decreased, and handling becomes easier.

[0013] In a further advantageous embodiment of the method, the method includes charging a first energy storage component of the energy storage device with energy stored in a second energy storage component of the energy storage device, and supplying the energy stored in the first energy storage component to a brake actuator.

[0014] When two energy storage components are used, the individual energy storage components can be optimized, i.e., on the one hand, a second energy storage device is used to have a large energy capacity for supplying energy for a large number of release operations, and on the other hand, a first energy storage device is used to supply a sufficient current peak value to enable the required speed of the actuator.

[0015] In a further advantageous embodiment of the method, the first energy storage component is a capacitor, the second energy storage component is a battery, and the first energy storage component is charged via a charger and a booster that controls the charging of the first energy storage component.

[0016] The battery provides an advantageous relationship between the charging capacity and the weight and size. The charger and the booster can optimize the discharge of the battery, particularly with respect to the discharge time of the second energy storage component and thus the charging time of the capacitor. By discharging the battery slowly while taking into account the time between individual release operations, a lighter battery can be used, the cost is reduced, and the handleability of the energy storage components is improved. A booster in the form of a voltage level booster is necessary to release the maximum energy from the battery and achieve the best operating voltage of the actuator.

[0017] In a further advantageous embodiment of the method, the supply to the brake actuator is effected via a discharge limiter of the energy store.

[0018] The use of a discharge limiter protects the energy storage device by ensuring a safe operating range for the first energy storage component.

[0019] According to a further aspect of the present invention, a portable energy storage device for supplying an electromechanical brake actuator for releasing an electromechanical brake includes a first energy storage component and a second energy storage component, the second energy storage component configured to charge the first energy storage component, and the first energy storage component configured to supply energy to the brake actuator.

[0020] When two energy storage components are used, the individual energy storage components can be optimized: on the one hand, the second energy storage device is used to reserve a large energy capacity to provide energy for multiple release operations, and on the other hand, the first energy storage device is used to provide sufficient current peak values to allow the required speed of the actuator, thereby optimizing the size and weight of the energy storage devices.

[0021] In an advantageous embodiment of the portable energy storage device, the first energy storage component is formed by a capacitor and the second energy storage component is formed by a battery.

[0022] By using a capacitor as the first energy storage component and a battery as the second energy storage component, the energy storage components can be optimized in terms of providing a sufficient amount of energy with appropriate parameters while optimizing the size and weight of the energy storage device.

[0023] In a further advantageous embodiment of the portable energy storage device, the battery is formed by one of a lithium-ion battery, a NiMH battery, and a lead battery.

[0024] These types of batteries enable an advantageous relationship between the charging capacity and the weight and size of the battery.

[0025] In a further advantageous embodiment of the portable energy storage device, the device further comprises a charger and a booster configured to control the charging of the first energy storage component.

[0026] The charger and the booster can optimize the discharging of the second energy storage component and thus the charging of the first energy storage component, particularly with respect to the discharging time of the second energy storage component.

[0027] In a further advantageous embodiment of the portable energy storage device, the device further comprises a discharge limiter configured to control the supply current supplied to the brake actuator.

[0028] By providing the discharge limiter, a safe operating range of the first energy storage component is ensured, thereby protecting the energy storage device.

[0029] In a further advantageous embodiment of the portable energy storage device, the device is configured to be portable.

[0030] Due to this characteristic, when a plurality of actuator groups are distributed along the train, it is easy to move from one actuator group to the next actuator group in order to release each brake actuator, thus facilitating the use of the energy storage device.

[0031] According to another aspect of the present invention, a system of a portable energy storage device and a train braking system includes a plurality of electromechanical brakes having brake actuators grouped into a plurality of brake actuator groups, wherein the brake actuator groups are configured such that a brake actuator of one of the brakes in the brake actuator group can be connected to the energy storage device by one connector device.

[0032] In such a system, there is no need to remove the actuator, and the additional equipment of the train is limited to the connector device for connecting the portable energy storage device to the actuator, and there is no need to complicate the vehicle wiring or add a large energy storage device to the train.

[0033] In an advantageous embodiment of the system, the brake actuator is configured such that the energy consumption during brake release is reduced by an empirically determined and optimized speed profile of the brake actuator.

[0034] Due to the optimized speed profile, the actuator operates according to the speed profile with the least energy consumption, so the required amount of energy, and thus the charging capacity of the energy storage device, is reduced, enabling the energy storage device to be made smaller and lighter. As a result, the cost is reduced and handling becomes easier.

[0035] According to a further aspect of the present invention, there is provided a computer program product having program code stored on a machine-readable carrier for executing a method.

[0036] Hereinafter, the present invention will be described by embodiments with reference to the accompanying drawings. In particular, the following is shown in the drawings.

Brief Description of the Drawings

[0037]

Figure 1

Figure 2

Figure 3

Figure 4

[0038] Figure 1 is a diagram showing a system 1 including a portable energy storage device 2 and a braking system 3 of a train. The braking system 3 includes an electro-mechanical brake (not shown) and a brake actuator 4 assigned to each electro-mechanical brake.

[0039] In this embodiment, four brake actuators 4 are grouped into a group of brake actuators 5. The brake actuators 4 of the group of brake actuators 5 can be connected to the energy storage device 2 by a cable 6 and a connector device (not shown). In an alternative embodiment, a different number of brake actuators 4 are grouped into the group of brake actuators 5, or the brake actuators 4 are not grouped into the group of brake actuators 5 and are individually connected to the portable energy storage device 2.

[0040] The energy consumption of the brake actuator 4 is reduced by determining the optimized speed profile of the brake actuator 4.

[0041] Figure 2 shows the speed profile and energy consumption of one of the brake actuators 4 at low speed. The horizontal axis of the figure indicates the elapsed time in [s], and the vertical axis indicates the speed in [rad / s] and the consumed energy in [J]. Figure 3 is a diagram showing the speed profile and energy consumption of one of the brake actuators 4 at the optimized speed. Also in this figure, the horizontal axis of the figure indicates the elapsed time in [s], and the vertical axis indicates the speed in [rad / s] and the energy consumption in [J].

[0042] As can be seen from Figure 2, the maximum speed of the actuator 4 is 20 rad / s, and the duration of one release procedure is about 3 s. In this case, for one release procedure, the energy consumption is 260 J. In Figure 3, it is shown that when the maximum speed of the actuator 4 is 50 rad / s and the duration of one release procedure is about 1.4 s, the energy consumption of the actuator 4 for one release procedure is 155 J.

[0043] Therefore, in order to reduce the energy consumption during brake release, an optimized speed profile should be determined by empirical tests. According to the results of this investigation, in order to shorten the operating time of the brake actuator 4, the speed profile should be designed so that the speed of the brake actuator 4 increases. Since the current is large but the operating time is shortened, the energy consumed to release the brake is reduced compared to the brake actuator 4 that operates at low speed with a long operating time.

[0044] The energy storage device 2 supplies energy for operating the electromechanical brake actuator in order to release the brakes of the train when the power supply of the train fails.

[0045] The portable energy storage device 2 shown in Fig. 1 includes a first energy storage component 7 and a second energy storage component 8. The second energy storage component 8 is configured to charge the first energy storage component 7, and then the first energy storage component is configured to supply energy to the brake actuator 4. The portable energy storage device 2 is configured to be portable, but in an alternative embodiment, it is provided with casters so as to be movable, for example.

[0046] The first energy storage component 7 is formed by a capacitor bank that uses capacitor, especially super / ultra capacitor technology that significantly reduces the weight of the first energy storage component 7. In an alternative embodiment, the first energy storage component 7 can also be formed by another type of energy storage component that provides appropriate operating characteristics.

[0047] The second energy storage component 8 is formed by a battery, especially a lithium-ion battery. In an alternative embodiment, the second energy storage component 8 can be formed by a NiMH battery, a lead-acid battery, or another suitable type of battery.

[0048] The capacitor bank that is the first energy storage component 7 and the battery that is the second energy storage component 8 provide the following advantages. Since the battery has an advantageous relationship between the charge capacity and the weight and size, it can store more energy for multiple release procedures without excessively increasing the size and weight of the portable energy storage device. However, the battery cannot supply the high peak current required to achieve the high speed of the actuator 4. Therefore, the capacitor bank, which has a small charge capacity but is sufficient for one release procedure, is used to supply a high peak current without requiring a large charge capacity because it can be charged by the battery after each release procedure.

[0049] The portable energy storage device 2 further includes a charger and booster 9 and a discharge limiter 10.

[0050] The charger and booster 9 control the charging of the first energy storage component 7. The charger and booster 9 enable the first energy storage component 7 to be charged by discharging the second energy storage component 8 in an optimized manner. The discharging of the second energy storage component 8 is carried out as slowly as possible so that a lighter battery can be used. Nevertheless, it is borne in mind that the first energy storage component 7 should be fully charged after being disconnected from the last actuator group 5 and before being connected to the next actuator group 5. In particular, the booster can discharge the maximum energy from the battery and achieve the best operating voltage for the actuator 4.

[0051] The discharge limiter 10 is configured to control and limit the supply current supplied to the brake actuator 4. Thus, the discharge limiter 10 ensures the safe operating range of the capacitor bank and thus protects the energy storage device 2.

[0052] Figure 4 shows a flowchart of a method for releasing the electromechanical brakes of the train braking system 3.

[0053] During use, if a fault occurs in the train's power supply but the train has to be moved, for example, to the next station, the electromechanical brakes of the train braking system 3 have to be released by the respective assigned brake actuators 4. The following procedure can be carried out on the premise that the second energy storage component 8 is fully charged.

[0054] In step S1, the brake actuator 4, particularly the actuator group 5 when grouped into actuator groups 5, is sequentially connected to the portable energy storage device 2 that supplies electrical energy for releasing the brakes. The connection procedure is carried out by connecting a connector device having two connector parts, one of which is coupled to the portable energy storage device 2 and the other is coupled to the brake actuator 4.

[0055] In step S2, the brake actuator 4 supplied with energy from the portable energy storage device 2 is activated. As a result, the energy stored in the first energy storage component 7 of the portable energy storage device is supplied to the brake actuator 4, and thus the brake in the locked state is released. The brake actuator 4 is activated by a switch included in the portable energy storage device 2. Alternatively, the switch is assigned to the brake actuator 4.

[0056] These two steps S1 and S2 are repeated until all the brakes of the train brake system 3 are released. When all the brakes of the brake system 3 are released, the train can be moved.

[0057] In step S3, the first energy storage component 7 of the energy storage device 2, i.e., the capacitor bank, is charged by the energy stored in the second energy storage component 8 of the energy storage device 2, i.e., the lithium-ion battery. If the energy storage device 2 has a different structure, the energy storage component that supplies energy to the brake actuator 4 can be charged in another way as long as a sufficient amount of energy is available.

[0058] The capacitor bank is charged via the charger and booster 9 so that the charging of the first energy storage component 7 is controlled by the charger and booster 9. In an alternative embodiment, if the charger and booster 9 are not available, the charging of the first energy storage component 7 is controlled by another electronic device.

[0059] The supply to the brake actuator 4 is performed via the discharge limiter 10 of the energy storage device 2. Thereby, the discharge limiter 10 protects the energy storage device 2 by ensuring the safe operating range of the capacitor bank. In an alternative embodiment, if the discharge limiter 10 is not available, the energy storage device 2 is protected in another way or the protection is omitted.

[0060] The method may be performed by means of a computer program product stored on a machine-readable carrier, or the method may be performed in another suitable manner, for example by means of a hardwired device.

[0061] While the invention has been described with reference to particular features and embodiments thereof, it will be apparent that various modifications and combinations are possible without departing from the spirit and scope of the invention. Accordingly, the specification and drawings are to be regarded as merely illustrative of the invention as defined by the appended claims, and it is intended to cover any modifications, variations, combinations or equivalents that fall within the scope of the invention. [Explanation of symbols]

[0062] 1 System 2 Portable energy storage devices 3. Brake system 4 Brake Actuator 5 Brake actuators 6 Cables 7 First energy storage component 8 Second energy storage component 9 Chargers and Boosters 10 Discharge Limiter

Claims

1. A method for releasing an electromechanical brake by means of an electromechanical brake actuator (4) assigned to each, comprising: sequentially connecting the brake actuator (4) to a portable energy storage device (2) that supplies electrical energy for releasing the brake; releasing the brake by operating the brake actuator (4) using the energy from the portable energy storage device (2); wherein the brake actuator (4) is operated according to a speed profile empirically determined such that the total energy consumption of the brake actuator (4) during the brake release time is minimized to enable energy-saving release of the brake.

2. The brake actuator (4) is grouped into a plurality of brake actuator groups (5), and the supply to the brake actuator groups (5) is performed sequentially and individually by the portable energy storage device (2). The method according to claim 1.

3. The method further comprises charging a first energy storage component (7) of the energy storage device (2) with the energy stored in a second energy storage component (8) of the energy storage device (2); supplying the energy stored in the first energy storage component (7) to the brake actuator (4). The method according to claim 1.

4. The first energy storage component (7) is formed by a capacitor, the second energy storage component (8) is formed by a battery, and the first energy storage component (7) is charged via a charger and booster (9) that controls the charging of the first energy storage component (7). The method according to claim 3.

5. The supply to the brake actuator (4) is performed via a discharge limiter (10) of the energy storage device (2).

6. A portable energy storage device (2) for supplying an electromechanical brake actuator (4) for releasing an electromechanical brake, comprising a first energy storage component (7); a second energy storage component (8); wherein the second energy storage component (8) is configured to charge the first energy storage component (7). The first energy storage component (7) is configured to supply energy to the brake actuator (4). A portable energy storage device (2).

7. The first energy storage component (7) is formed by a capacitor, The second energy storage component (8) is formed by a battery. The portable energy storage device (2) according to claim 6.

8. The battery is formed by one of a lithium ion battery, a NiMH battery, and a lead battery. The portable energy storage device (2) according to claim 7.

9. The portable energy storage device (2) further includes A charger and a booster (9) configured to control charging of the first energy storage component (7) The portable energy storage device (2) according to claim 6, comprising.

10. The portable energy storage device (2) further includes A discharge limiter (10) configured to control the supply current supplied to the brake actuator (4) The portable energy storage device (2) according to claim 6, comprising.

11. The portable energy storage device (2) is configured to be portable. The portable energy storage device (2) according to claim 6.

12. A system (1) including the portable energy storage device (2) according to any one of claims 6 to 11 and a brake system (3) of a train, The system (1) includes a plurality of electromechanical brakes including brake actuators (4) grouped into a plurality of brake actuator groups (5), The brake actuator group (5) is configured such that one brake actuator of the brake actuator group (5) can be connected to the energy storage device (2) by one connector device. System (1).

13. The brake actuator (4) is configured such that energy consumption during release of the brake is reduced by an empirically determined and optimized speed profile of the brake actuator (4). The system (1) according to claim 12.

14. A computer program product having program code stored on a machine-readable carrier for performing the method according to any one of claims 1 to 5.

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