Method for controlling a braking force of a brake system of a vehicle, and brake system for carrying out the method

Abstract

A method for controlling a braking force of a brake system of a vehicle by means of a control device is provided. The method comprises the following steps: if there is a positive control difference between a braking force setpoint value (Bremskraft_Set) and a braking force actual value (Bremskraft_Ist): determining a first torque setpoint value (Drehmoment_Set 1); inputting the torque setpoint value as a manipulated variable (Drehmoment_Set) into a controlled system (14) of the brake system; and adjusting the braking force on the basis of the input manipulated variable (Drehmoment_Set); if there is a negative control difference between the braking force setpoint value and the braking force actual value after a preceding positive control difference: determining a second torque setpoint value (Drehmoment_Set 2) from the control difference; calculating a compensated manipulated variable (Drehmoment_Set) by subtracting a hysteresis value (Drehmoment_Hyst) from the second torque setpoint value (Drehmoment_Set 2); inputting the compensated manipulated variable (Drehmoment_Set) as the manipulated variable into the controlled system (14) of the brake system; and adjusting the braking force on the basis of the input compensated manipulated variable (Drehmoment_Set).

Description

[0001] 2023PF00337 October 2, 2024

[0002] 1

[0003] DESCRIPTION

[0004] Method for controlling the braking force of a vehicle's braking system and braking system for executing the method

[0005] The invention relates to a method for controlling a braking force of a vehicle's braking system and a braking system for carrying out the method, in particular for braking systems with hysteresis.

[0006] The braking force of a rail vehicle is typically controlled nowadays using a PID controller in a cascade structure, specifically as speed or force control. This involves calculating an integral component over the entire control range. In systems with hysteresis, this integral component must also be integrated across the entire hysteresis range to achieve the desired manipulated variable. However, this calculation usually consumes the largest portion of the total control time in dynamic systems, often resulting in poor performance from this type of controller. Consequently, optimal control, particularly in the case of wheel slip protection, can be difficult or even impossible.

[0007] The object underlying the invention is therefore to solve the above problems and to provide a method that enables improved control of a braking force in dynamic systems.

[0008] The problem is solved by a method according to claim 1, a braking system according to claim 12, a rail vehicle according to claim 14, and a road vehicle according to claim 15. Advantageous further developments are included in the dependent claims.

[0009] According to one aspect of the invention, a method for controlling the braking force of a vehicle's braking system by means of a control device comprises the following steps: In the event of a positive control difference between a setpoint braking force and an actual braking force: Determining a setpoint torque from 2023PF00337

[0010] 2. The control error is calculated by inputting the torque setpoint as a manipulated variable into a controlled system of the braking system and adjusting the braking force based on the input manipulated variable, starting from a given current manipulated variable. If a negative control error exists between the brake force setpoint and the brake force actual value after a previous positive control error, a second torque setpoint is determined from the control error, a compensated manipulated variable is calculated by subtracting a hysteresis value from the second torque setpoint, the compensated manipulated variable is input as the manipulated variable into the controlled system of the braking system, and the braking force is adjusted based on the input compensated manipulated variable, starting from the given current manipulated variable.

[0011] Here, a positive control deviation between the target and actual braking force values ​​is defined as requiring an increase in braking force, i.e., braking should be initiated or applied more strongly. A negative control deviation between the target and actual braking force values ​​is defined as requiring a decrease in braking force, i.e., releasing the brakes or applying less braking force.

[0012] The hysteresis value defines a range in which, when the manipulated variable changes, there is no change in the braking force, and depends on the type and design of the brake in the braking system.

[0013] By calculating the compensated control variable by subtracting the hysteresis value from the control variable determined from the control error and inputting the compensated control variable, the control variable range in which the hysteresis of the braking system occurs can be quickly traversed, thus compensating for the hysteresis in the braking system. This eliminates the need for complex integral control in this hysteresis range, allowing for faster and more accurate control. 2023PF00337

[0014] 3

[0015] According to an advantageous further development of the method, the hysteresis value is determined in advance as a function of a braking torque.

[0016] In an advantageous further development of the method, the control device has an integral controller, the manipulated variable has an integral manipulated variable component determined by the integral controller, and furthermore, a maximum value of the manipulated variable, up to which no further increase in braking force occurs when the manipulated variable is increased, is defined as the initial manipulated variable.

[0017] In an advantageous further development of the method, when a control error is balanced after outputting the manipulated variable or compensated manipulated variable, the following steps are performed: monitoring the integral manipulated variable component currently output by the integral controller, determining a current difference between the integral manipulated variable component currently output by the integral controller as the present current manipulated variable and the input manipulated variable by subtracting the currently output integral manipulated variable component from the input manipulated variable, and reducing the hysteresis value by the current difference by subtracting the current difference from the hysteresis value.

[0018] In an advantageous further development of the method, the manipulated variable is a torque setpoint of a braking torque to be applied by a motor.

[0019] In an advantageous embodiment of the method, the torque setpoint is controlled by means of a proportional controller and a forward control.

[0020] According to an advantageous embodiment of the method, the control difference between the setpoint braking force and the actual braking force is converted into a first setpoint speed in a first outer cascade, and a control difference between the first setpoint speed and an actual speed is converted into the manipulated variable in a first inner cascade.

[0021] In an advantageous further development of the method, if the distance between a braking element and an element to be braked is greater than 2023PF00337

[0022] 4. If a predetermined value is present, a control deviation from a position setpoint of a braking element of the braking system and a position actual value of the braking element is converted in a second outer cascade into a second speed setpoint, and a control deviation from the second speed setpoint and the speed actual value is converted in a second inner cascade into the manipulated variable, and if the distance between the braking element and the element to be braked is less than or equal to the predetermined value, the control deviation from the braking force setpoint and the braking force actual value is converted into the manipulated variable.

[0023] In an advantageous embodiment of the method, the actual speed value is determined from a position of the braking element using a differentiation filter.

[0024] In a further advantageous embodiment of the method, the transfer to the outer cascades is carried out using a proportional controller.

[0025] According to an advantageous embodiment of the method, the transfer in the inner cascades is carried out using a proportional-integral controller.

[0026] According to another aspect of the invention, a braking system of a vehicle is provided which is designed to perform a previously described method.

[0027] In an advantageous further development of the braking system, it features an electromechanical actuator.

[0028] In another aspect of the invention, a rail vehicle has such a braking system.

[0029] According to another aspect of the invention, a road vehicle has such a braking system. 2023PF00337

[0030] 5

[0031] The invention is explained below by means of exemplary embodiments with reference to the accompanying drawings.

[0032] In particular, it shows:

[0033] Fig. 1 shows a block diagram of an electromechanical braking system according to the invention of a vehicle;

[0034] Fig. 2 shows a hysteresis diagram in which a torque applied to a spindle of a brake actuator is plotted on its x-axis and a braking force applied by a braking element to an element to be braked is plotted on its y-axis;

[0035] Fig. 3 shows, in principle, a process of hysteresis compensation according to a first embodiment of a method for controlling a braking force of the vehicle;

[0036] Fig. 4 shows, in principle, the process of hysteresis compensation according to a second embodiment of the method for controlling a vehicle's braking force without a corrected hysteresis value; and

[0037] Fig. 5 shows in principle the process of hysteresis compensation according to the second embodiment of the method for controlling a vehicle's braking force with a corrected hysteresis value.

[0038] Fig. 1 shows a block diagram of an electromechanical braking system 1 according to the invention of a vehicle Fz. The vehicle Fz is designed as a rail vehicle. In alternative embodiments, the vehicle Fz can also be designed as a road vehicle.

[0039] The braking system 1 has a so-called state machine 2, which determines various states of the braking system 1, for example, whether brake actuators 2023PF00337

[0040] 6 are released, and / or whether brake pads are in contact with a brake disc, or whether it is necessary to apply or release the brake.

[0041] Furthermore, the braking system 1, which is delimited in the block diagram by a dashed line, has components for position control in a position control section 3 and components for force control in a force control section 4.

[0042] In the position control section 3, the braking system 1 has, in a first outer cascade, a controller position 5 which has a proportional controller, and, in a first inner cascade, a controller speed 6 which has a proportional-integral controller.

[0043] In the force control section 4, the braking system 1 has, in a second outer cascade, a force controller 7 which has a proportional controller, in a second inner cascade, a speed controller 8 which has a proportional-integral controller and a so-called feedforward control, a hysteresis compensator 9 and a subtractor 15.

[0044] Furthermore, the brake system 1 includes a position sensor 10 and a differential filter 11. A force sensor 12 is also provided in the brake system 1.

[0045] In addition, a so-called switch 13, which switches between different torque setpoints “Torque_Set” and passes them through, and a so-called control loop 14 are provided in the brake system 1.

[0046] The control loop 14 comprises a motor control device, a motor, and a mechanical assembly as electromechanical actuators of the brake actuator, as well as a brake caliper with brake pads that acts on a brake disc. In the control loop 14, a torque setpoint input as a manipulated variable is converted into a braking force of the brake system 1. In alternative embodiments, the motor control device and the motor are not provided in the control loop 14, but rather a different type of 2023PF00337

[0047] 7

[0048] A control device for a different type of drive element, for example a pneumatic or hydraulic cylinder, and / or a different type of mechanism, for example a brake caliper, is provided. In such alternative embodiments, instead of torque setpoints, suitable setpoints, for example corresponding pressure setpoints, are entered as control values. In further alternative embodiments, brake linings and brake discs are not provided, but for example brake drums. For this reason, such elements are subsequently referred to as "braking elements" and "elements to be braked" of the brake system 1.

[0049] Fig. 2 shows a hysteresis diagram in which a torque M applied by a brake motor to a spindle of an electromechanical brake actuator is plotted on its x-axis and a braking force F applied by the braking element to the element to be braked is plotted on its y-axis.

[0050] The diagram shows a series of graphs to illustrate the phenomenon of "hysteresis." It demonstrates that, starting from the origin (the value "0" on both the x-axis and the y-axis), an increase in torque M to the right in the diagram does not initially result in an increase in braking force F. Only after a first threshold value SW1 of torque M is reached, two of which are shown in the diagram as examples, does the braking force F increase approximately linearly. The effect that the braking force F only increases after the first threshold value can be caused, for example, by the inertia of components in the brake actuator and / or static friction between two components, which then transitions into sliding friction.The braking force F then increases along one of the graphs shown until the braking torque M reaches a point where a desired corresponding braking force F is present due to the torque M.

[0051] If the torque M is subsequently reduced to the left in the diagram, the braking force F does not decrease immediately, for example due to inertia and / or static friction between two components, but rather 2023PF00337

[0052] 8 only at a second threshold value SW2, two of which are also shown as examples. The hysteresis or hysteresis width "torque_hyst" thus results from the braking torque range in which the graph is horizontal, meaning that a change in the braking torque M does not result in a change in the braking force F. The hysteresis diagram also shows that the torque "M" must be negative in order to reduce the braking force back to "0". In an alternative embodiment, for example, if a restoring force exists, the torque "M" can also be "0" or even positive when the brake pads are retracted.

[0053] The graphs shown are merely examples to illustrate the basic system. The numerical values ​​on the x-axis and y-axis are dimensionless and intended only to explain the fundamental function.

[0054] During operation, for a braking process, a braking force request "Brake Force_SoH" for a required braking force is input into the control unit 1 from a control device of the vehicle Fz (not shown) into the state machine 2. The braking force F from this braking force request "Brake Force_SoH" is then controlled by the procedures described below.

[0055] If the distance between the braking element and the element to be braked is greater than a predetermined value, meaning the braking element is not in a predetermined contact position where it at least approximately touches the element to be braked, the braking force request "Braking force_SoH" is converted by state machine 2 into a position setpoint "Position_Set" and entered into the position control section 3. The position request "Position_Set" is compared with an actual position "Position_lst" of a component of the controlled system 14, for example, the braking element, which is determined by the position sensor 10.

[0056] A control difference between a target position value “Position_Set” of the braking element of brake system 1 and a current position value “Position_lst” of the braking element is then entered into the controller position 5 in the first outer 2023PF00337

[0057] 9

[0058] The cascade is entered and converted into a first target speed value "Speed_Set 1". The first target speed value "Speed_Set 1" is then compared with an actual speed value "Speed_lst", which is obtained from the actual position determined by the position sensor 10 using the differentiation filter 11.

[0059] A control difference between the first speed setpoint “Speed_Set 1” and the actual speed “Speed_actual” is converted via the controller speed 6 in the first inner cascade into a first torque setpoint “Torque_Set 1” and via the switch 13 as manipulated variable “Torque_Set” into the control loop 14, in which this manipulated variable is converted via the motor control device and the motor, so that the braking element moves into the predetermined contact position.

[0060] The position control in position control area 3 is active after the input of the braking force request “braking force_target” into the state machine 2 until the predetermined application position of the braking element is reached at least within a predetermined tolerance range.

[0061] After reaching the predetermined application position, i.e., when the distance between the braking element and the element to be braked is less than or equal to the predetermined value, the state machine 2 switches to force control, whereby a setpoint braking force "Brake force_Set" is entered from the state machine 2 into the force control section 4.

[0062] In force control section 4, the setpoint brake force "Brake force_Set" is compared with the actual brake force value "Brake force_actual" in the control loop 14, which is determined by force sensor 12. Furthermore, the actual brake force value "Brake force_actual" is also input into state machine 2 to, for example, determine the state in which the brake pads are in contact with the brake disc.

[0063] A control difference between the setpoint braking force "Bremskraft_Set" and the actual braking force "Bremskraft_lst" is used to control the manipulated variable 2023PF00337

[0064] 10

[0065] The "Torque_Set" is used and is entered into the controller force 7 in the second outer cascade. Controller force 7 then converts this value into a second setpoint velocity "Speed_Set 2". Controller speed 8 in the second inner cascade converts the control difference between the second setpoint velocity "Speed_Set 2" and the actual velocity "Speed_actual" into a second setpoint torque "Torque_Set 2", and this second setpoint torque "Torque_Set 2" is entered into the subtractor 15.

[0066] In the hysteresis compensator 9, a hysteresis compensation as described below is performed and, if necessary, a hysteresis value “Torque_Hyst” or corrected hysteresis value “Torque_Hyst_korr” to be subtracted from the second torque setpoint “Torque_Set 2” as a manipulated variable is entered from the hysteresis compensator 9 into the subtractor 15.

[0067] In the subtractor element 15, the hysteresis value “Torque_Hyst” or corrected hysteresis value “Torque_Hyst_corr” to be subtracted, if any, is subtracted from the second torque setpoint “Torque_Set 2” and a compensated manipulated variable “Torque_Set” is entered into the control loop 14 via the switch 13 as a manipulated variable “Torque_Set”.

[0068] During the braking process, in which the braking force request “braking_force_target” entered into the state machine 2 may also be in a range where the control difference in the range varies greater than “0”, the force control in the force control section 4 is active and remains active until the braking force request “braking_force_target” entered into the state machine 2 is “0” and the actual braking force value “braking_force_actual” is less than a predetermined threshold value, in this embodiment 200 N.

[0069] When the braking force request “Brake force_target” of “0” is entered into state machine 2 and the actual braking force value “Brake force_actual” is less than the predetermined threshold, state machine 2 switches to 2023PF00337

[0070] 11

[0071] Position control. Using position control, a position is then approached in which the braking element assumes a predetermined distance from the element to be braked, in this embodiment approximately 8 mm.

[0072] In an alternative embodiment, the position control and the state machine are not provided; instead, only the force control is implemented.

[0073] Hysteresis compensation is performed in the hysteresis compensator 9.

[0074] For hysteresis compensation, a fundamental distinction is made as to whether the speed request “Speed_Set” entered in the controller speed 8 is greater or less than the last entered speed request “Speed_Set”, i.e., whether the braking force should be increased or decreased.

[0075] If the braking force is to be increased, the control error, i.e., the input of controller force 7, is greater than 0, resulting in a positive control error between the setpoint braking force "Brake Force_Set" and the actual braking force "Brake Force_actual". This control error is detected, and a torque setpoint is determined as a manipulated variable "Torque_Set" via controller force 7 and controller speed 8. This manipulated variable "Torque_Set" is fed into the controlled system 14 of braking system 1, and the braking force is adjusted based on the input manipulated variable, starting from a given current manipulated variable.

[0076] Due to the increase in braking force by the motor control and the motor itself, the actual braking force value “Brake force_actual” determined via force sensor 12 reaches the value of the braking force request “Brake force_set”, and the motor is controlled via controller force 7 and controller speed 8 to stop, as the control difference is balanced. 2023PF00337

[0077] 12

[0078] If the braking force is to be reduced, the control error, i.e., the input of controller force 7, is less than 0, resulting in a negative control error between the setpoint braking force "Brakeforce_Set" and the actual braking force "Brakeforcejst". This leads to a reduction of the manipulated variable "Torque_Set", which is input into the controlled system 14 via subtractor 15 and switch 13.

[0079] In a first embodiment of the control method of the brake system 1, the hysteresis compensation is carried out by the fact that, in the event of a negative control difference between the brake force setpoint “Brake force_Set” and the brake force actual value “Brake force_actual value” after a previous positive control difference, the control difference between the brake force setpoint “Brake force_Set” and the brake force actual value “Brake force_actual value” is again detected and, via the controller force 7 and the controller speed 8, the torque setpoint “Torque_Set 2” is determined from the control difference. Subsequently, by subtracting a hysteresis value “Torque_Hyst” from the torque setpoint “Torque_Set 2” using the subtractor 15, a compensated control variable is calculated to compensate for the hysteresis occurring in the braking system 1 and is entered into the control loop 14 as the control variable “Torque_Set”.In control loop 14, the braking force is set based on the input compensated control variable, starting from the current control variable.

[0080] The hysteresis value "TorqueJHyst" of the braking system 1 is empirically determined in advance as a function of an applied braking torque and is expressed by a characteristic curve. From this characteristic curve, the hysteresis values ​​"TorqueJHyst" for the respective current torque values ​​can be determined. As already indicated for Fig. 2, the hysteresis value "Torque_Hyst" specifies the value for a torque range in which the force does not change, or hardly changes, despite changes in torque. In alternative embodiments, the hysteresis value can also be estimated.

[0081] Figure 3 illustrates the basic process of hysteresis compensation according to the first embodiment of the method for controlling the braking force F of the vehicle Fz. Figure 3 shows, based on the diagram in Figure 2, a single 2023PF00337

[0082] 13. The basic course of the hysteresis compensation according to the first embodiment is given. It is assumed that a braking characteristic curve B passes through the origin of the coordinate system and that a characteristic curve with release torques L is shifted negatively by the hysteresis value "torque_hyst".

[0083] For braking, for example, a target torque value (braking torque) of approximately "2.4" is entered as the manipulated variable "Torque_Set" into the control loop 14, resulting in a braking force "F" of approximately "3.1".

[0084] When the braking force request "Braking force_SoH" is reduced, the hysteresis value "Torque_Hyst" in the subtractor 15 is subtracted from the control variable "Torque_Set" (braking torque M) last entered into the control loop 14 when the braking force F was increased. This allows the hysteresis range to be quickly traversed when the brake is released with a control variable "Torque_Set" that has already been reduced by the hysteresis range of the braking system 1.

[0085] In a second embodiment of the control method of the braking system 1, fluctuations in the control difference are taken into account more precisely.

[0086] For this second embodiment of the control method, the control device has the integral controller at controller speed 8 and the manipulated variable, namely the torque setpoint “Torque_Set”, has an integral manipulated variable component IDS determined by the integral controller.

[0087] Figures 4 and 5 show, in principle, a sequence of hysteresis compensation according to the second embodiment of the control method, with Figure 4 showing the control method without a corrected hysteresis value and Figure 5 showing the control method with a corrected hysteresis value.

[0088] The principle of this hysteresis compensation is explained using the torque-force equation.

[0089] The course is explained in principle in the hysteresis diagram of Fig. 4. A point P represents the 2023PF00337

[0090] 14

[0091] The value at which an intended braking force F, in this example approximately "5", is achieved by a torque "M" of approximately "4" specified by the forward control and the proportional controller. To achieve this intended braking force F of approximately "5", the manipulated variable of the torque setpoint "Torque_Set" of approximately "4" is input into the controlled system 14 via the controller force 7 and the controller speed 8.

[0092] The so-called integral control variable component IDS of the proportional-integral controller at controller speed 8, which arises during control when the braking request "torque_SoH" is increased, is added to a proportional control variable component at point P. This results in a torque value that corresponds to a value shifted to the right along the hysteresis curve A until it reaches the maximum value of the manipulated variable on this hysteresis curve A, the so-called push-pull variable X. This push-pull variable X is the maximum value up to which an increase in the manipulated variable does not result in an increase in the braking force F. A further increase in the manipulated variable again leads to an increase in the braking force. In the case shown, for a braking force value F of approximately 5, the torque value is approximately...5.1, which is then actually entered into the controlled system 14 as the manipulated variable "Torque_Set", i.e., as the sum of the proportional manipulated variable component and the integral manipulated variable component IDS. With a further increase in the torque "M", the braking force "F" would also increase.

[0093] Due to minimal systematic inaccuracies in the control deviation entered into the controller speed 8, for example from an offset in the actual speed value “speed_lst”, such as due to inaccuracies in the position sensor 10 or in the differentiation filter 11, the integral manipulated variable component IDS can change during braking, i.e. after a balanced control deviation, without the braking force instruction value “braking_force_SoH” being changed.

[0094] Increasing the integral control variable component IDS of the proportional-integral controller of controller speed 8 increases the control variable "Torque_Set", and the braking force F increases minimally, which is so long from a control engineering perspective that 2023PF00337

[0095] 15 remains unaffected until a limit is exceeded and the controller force 7 reacts and issues a speed request “Speed_Set” to reduce the braking force again.

[0096] When the integral control variable component IDS of the proportional-integral controller of controller speed 8 is reduced, the control variable "torque_Set" decreases and the control variable "torque_Set" "moves", as shown in Fig. 4 as an example of the current integral control variable component lDs_act, to the left in the horizontal area on graph A.

[0097] When the control deviation is balanced after output of the manipulated variable or the compensated manipulated variable, i.e. when the actual braking force value "Brake_force_actual" corresponds to the set braking force value "Brake_force_set", the hysteresis compensator 9 monitors the integral manipulated variable component lDs_actual currently output by the integral controller.

[0098] Assuming that the current integral control variable lDs_akt of the proportional-integral controller at controller speed 8 decreases, the control variable and the torque setpoint "Torque_Set" move to the left in the horizontal region on graph A during this decrease. Thus, as shown in Fig. 4, subtracting the hysteresis value "Torque_Hyst" from the currently available control variable "Torque_Set" (i.e., from the current integral control variable los_akt) results in a compensated control variable for a release torque L, the value of which is unduly reduced.

[0099] For this reason, as shown in Fig. 5, based on monitoring the current integral control variable component los_akt, a current difference A is determined from the integral control variable component los_akt currently output by the integral controller as the current control variable and the input control variable X by subtracting the currently output integral control variable component los_akt from the input control variable X, and the hysteresis value "Torque_Hyst" is reduced by the current difference A, resulting in a corrected hysteresis value "Torque_Hyst_korr". This corrected hysteresis value "Torque_Hyst_korr" is then subtracted from the control variable (Torque_Set 2) from the controller by the subtractor 15. 2023PF00337

[0100] 16

[0101] Velocity 8 is subtracted to determine the compensated control variable "Torque_Set" and input it into the controlled system 14, whereby the braking force F is then set based on this compensated control variable "Torque_Set" starting from the current control variable from the integral control variable component los_akt.

[0102] This allows, firstly, the hysteresis range to be traversed quickly, preventing the integral component from having to be integrated across the entire hysteresis range to achieve the desired control variable, thus resulting in better control performance. Secondly, the control variable "Torque_Set" is not excessively reduced, eliminating the risk of brake force control becoming unstable.

[0103] 2023PF00337

[0104] 17

[0105] REFERENCE MARK LIST

[0106] 1. Braking system

[0107] 2 State machine

[0108] 3 Position Control Section

[0109] 4 Force control section

[0110] 5 control positions

[0111] 6 Controller speed

[0112] 7 Regulator force

[0113] 8 Controller speed

[0114] 9 Hysteresis compensator

[0115] 10 Position sensor

[0116] 11 Differentiation filters

[0117] 12 Force sensor

[0118] 13 switch

[0119] 14 Control loop

[0120] 15 subtractor

[0121] Brake force_lst Actual brake force value

[0122] Braking force set braking force target value

[0123] Brake force_target Brake force instruction value

[0124] Torque_start Start adjustment variable

[0125] Torque_Set (compensated) manipulated variable

[0126] Torque_Set 1 Control variable

[0127] Torque_Set 2 Control variable

[0128] F braking force

[0129] Vehicle

[0130] Torque_Hysteresis value

[0131] Torque_hyst_corr corrected hysteresis value

[0132] Speed_lst Actual Speed ​​Value

[0133] Speed_Set Speed ​​Target Value

[0134] IDS Integral Control Variable Component lDS_akt Currently output integral control variable component 2023PF00337

[0135] 18

[0136] L release torque

[0137] M braking torque

[0138] Position_Set Position-Set value

[0139] Position 1st Position - Actual Value Current Difference

Claims

2023PF00337 19 PATENT CLAIMS 1. Method for controlling a braking force of a braking system (1) of a vehicle (Fz) by means of a control device, comprising the steps: in the event of a positive control difference between a setpoint braking force (Brakeforce_Set) and an actual braking force (Brakeforce_Ist): Determining a first torque setpoint (Torque_Set 1 ) from the control deviation; Input of the torque setpoint (Torque_Set 1 ) as a manipulated variable (Torque_Set) into a controlled system (14) of the braking system (1 ); and Adjusting the braking force based on the input control variable (torque_set) starting from a given current control variable; in the event of a negative control difference between the braking force setpoint (braking_force_set) and the actual braking force value (braking_force_actual) after a previous positive control difference, Determining a second torque setpoint (Torque_Set 2) from the control deviation; Calculating a compensated control variable (Torque_Set) by subtracting a hysteresis value (Torque_Hyst) from the second torque setpoint (Torque_Set 2); Inputting the compensated manipulated variable (torque_set) as the manipulated variable into the controlled system (14) of the braking system (1); and Adjusting the braking force based on the entered compensated control variable (torque_set) starting from the current control variable.

2. Method according to claim 1, wherein the hysteresis value (torque_hyst) is determined in advance as a function of a braking torque.

3. Method according to one of claims 1 or 2, wherein the control device comprises an integral controller, and the manipulated variable (torque_set) comprises an integral manipulated variable component (IDS) determined by the integral controller, 2023PF00337 20 and a maximum value of the manipulated variable (torque_set), up to which no further increase in braking force occurs when the manipulated variable (torque_set) is increased, is defined as the push-start manipulated variable (torque_push).

4. Method according to claim 3, wherein, in the event of a control deviation that is balanced after output of the manipulated variable (torque_set) or compensated manipulated variable (torque_set), the following steps are performed: Monitoring the integral input component (IDS) currently output by the integral controller; Determining a current difference (A) between the integral control variable component (los_akt) currently output by the integral controller as the present current control variable and the initial control variable (Drehmoment_Anschub); and Decreasing the hysteresis value (torque_hyst) by the current difference.

5. Method according to one of the preceding claims, wherein the manipulated variable (torque_set) is a torque setpoint of a braking torque (M) to be applied by a motor.

6. Method according to claim 5, wherein the torque setpoint is controlled by means of a proportional controller and a forward control.

7. Method according to claim 5 or 6, wherein the control difference from the setpoint braking force (brake_force_set) and the actual braking force (brake_force_lst) is converted in a first outer cascade into a first setpoint speed (speed_set 1), and a control difference from the first setpoint speed (speed_set 1) and an actual speed (speed_st) is converted in a first inner cascade into the manipulated variable (torque_set).

8. Method according to claim 7, wherein if a distance between a braking element and an element to be braked is greater than a predetermined value, 2023PF00337 21 a control difference from a position setpoint (Position_Set) of a braking element of the braking system (1) and a position actual value (Position_lst) of the braking element is converted in a second outer cascade into a second speed setpoint (Speed_Set 2), and a control difference from the second speed setpoint (Speed_Set 2) and the speed actual value (Speed_lst) is converted in a second inner cascade into the manipulated variable (Torque_Set), and when the distance between the braking element and the object to be braked If the element is less than or equal to the predetermined value, the control difference is calculated from the setpoint braking force (brake force_set) and the The actual braking force value (brake_force_actual) is converted into the manipulated variable (torque_set).

9. Method according to claim 8, wherein the actual speed value (speed_is) is determined from a position of the braking element using a differentiating filter (11).

10. Method according to one of claims 7 to 9, wherein a transfer in the outer cascades is carried out by means of a proportional controller.

11. Method according to one of claims 7 to 10, wherein a transfer in the inner cascades is carried out by means of a proportional-integral controller.

12. Braking system (1) of a vehicle (FZ) designed to perform a method according to one of the preceding claims.

13. Braking system (1) according to claim 12, wherein the braking system comprises an electromechanical actuator.

14. Rail vehicle (Fz) comprising a braking system (1) according to claim 12 or 13.

15. Road vehicle (VV) comprising a braking system according to claim 12 or 13.

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