US-12623551-B2 - Method for controlling a multitude of braking devices and braking system of a vehicle

US12623551B2US 12623551 B2US12623551 B2US 12623551B2US-12623551-B2

Abstract

A method for controlling a multitude of braking devices of a vehicle to effect a desired brake function quantified as a desired brake parameter, wherein each of the braking devices is controllable by an actuation parameter to effect at least a portion of said desired brake function, comprising the steps: determine, for each braking device, a brake capability representing a maximum brake function achievable by the braking device; determine, for each braking device, an actuation priority, wherein the actuation priority is determined from at least one predetermined operating parameter of the braking device and/or the vehicle; in order from highest priority to lowest priority of the braking means, allocating, to each braking device, the actuation parameter, wherein the actuation parameter is chosen between the brake capability and the quantity of the desired brake parameter not yet allocated to other braking devices, whichever is lower. Further, a braking system for a vehicle is configured to carry out the method.

Inventors

Huba NEMETH
Zoltan Toth
Tamas Dohany
Aron KUTAS
Gabor Liptak
Krisztian SANDOR

Assignees

KNORR-BREMSE SYSTEME FUER NUTZFAHRZEUGE GMBH

Dates

Publication Date: 20260512
Application Date: 20221014
Priority Date: 20211015

Claims (13)

1 . A method for controlling a multitude of braking devices of a vehicle to effect a desired brake function quantified as a desired brake parameter, wherein each of the braking devices is controllable by an actuation parameter to effect at least a portion of said desired brake function, the method comprising the steps of: determining, for each braking device, a brake capability representing a maximum brake function achievable by the braking device, determining, for each braking device, an actuation priority, wherein the actuation priority is determined from at least one predetermined operating parameter of the braking device and/or the vehicle; and in order from highest priority to lowest priority of the braking devices, allocating, to each braking device, the actuation parameter, wherein the actuation parameter is chosen between the brake capability and the quantity of the desired brake parameter not yet allocated to other braking devices, whichever is lower.
2 . The method according to claim 1 , wherein the desired brake parameter, the maximum actuation parameter and/or the actuation parameter each are expressed as one of the following: a torque, a force, a retardation.
3 . The method according to claim 1 , wherein when determining the actuation priority, braking devices comprising non-frictional brakes are determined to have a higher priority than braking devices comprising frictional brakes.
4 . The method according to claim 1 , wherein when determining the actuation priority, braking devices comprising regenerational brakes are determined to have a higher priority than braking devices comprising dissipational brakes.
5 . The method according to claim 4 , wherein when determining the actuation priority, the higher a regeneration efficiency of a regenerational brake, the higher its priority relative to other brakes comprising regenerational brakes.
6 . The method according to claim 1 , wherein when determining the actuation priority, one or more of the following parameters is taken into account: type or types of brake(s) comprised in the braking devices, efficiency of regenerational brakes comprised in the braking devices, recuperation ratio of regenerational brake devices comprised in the braking devices, current vehicle speed, current dynamic vehicle state, state of charge of a traction battery, axle load of the vehicle, individual loads on each axle of the vehicle, brake device response time, brake device response brake force, configurable priority value.
7 . The method according to claim 1 , wherein where a braking device comprises multiple brake devices, the actuation parameter is distributed among the multiple brake devices according to predefined and/or calculated distribution ratios.
8 . The method according to claim 1 , wherein when multiple braking devices are determined to have the same actuation priority, in the allocating step, the brake capabilities of the multiple braking devices determined to have the same actuation priority are conflated and the actuation parameter allocated to the multiple braking devices is distributed among the brake devices according to predefined and/or calculated allocation ratios.
9 . The method according to claim 1 , wherein, when determining the actuation priority, axle load of the vehicle and individual loads on each axle of the vehicle are taken into account.
10 . The method according to claim 1 , wherein, when determining the actuation priority, a current dynamic vehicle state is taken into account.
11 . A braking system of a vehicle, comprising: a first braking device comprising at least one frictional brake, a second braking device comprising at least one regenerative brake, and a control device, wherein the control device is configured to: determine, for each braking device, a brake capability representing a maximum brake function achievable by the braking device, determine, for each braking device, an actuation priority, wherein the actuation priority is determined from at least one predetermined operating parameter of the braking device and/or the vehicle; in order from highest priority to lowest priority of the braking devices, allocate, to each braking device, the actuation parameter, wherein the actuation parameter is chosen between the brake capability and the quantity of the desired brake parameter not yet allocated to other braking devices, whichever is lower.
12 . The braking system according to claim 11 , wherein, when determining the actuation priority, axle load of the vehicle and individual loads on each axle of the vehicle are taken into account.
13 . The braking system according to claim 11 , wherein, when determining the actuation priority, a current dynamic vehicle state is taken into account.

Description

BACKGROUND AND SUMMARY The present invention relates to a method for controlling a multitude of braking devices of a vehicle to effect a desired brake function as well as to a braking system of a vehicle. Electrical vehicles may be equipped with multiple driving motors which can be used as braking devices, in particular as regenerative brakes. Regenerative brakes produce electric current from kinetic energy to recuperate, when braking, a portion of the energy from the motion of the vehicle. Such vehicles may further be equipped with dissipative non-frictional brakes, for example eddy current brakes or electric retarders. This kind of brake may use resistive losses from eddy currents induced in moving parts to remove kinetic energy from the vehicle and dissipate it as heat. Furthermore, such vehicles may additionally be equipped with frictional brakes as well. Each of these brakes has a different operating capability in terms of achievable torque, force and/or acceleration. Furthermore, regenerative brakes may have varying operating capabilities in that they each may have a specific regeneration efficiency. When a desired brake function is to be achieved with such diverse braking devices, various goals, some of which are contradictory, need to be accounted for. For example, a steer-by-brake situation is to be avoided or one of the braking devices on its own may not be able to provide a sufficient brake function. Utilization of the brakes may have stability implications for the whole vehicle. For example, if brakes on left and right sides of a vehicle effect diverging braking torque, they may drag the vehicle in one direction. This effect is called steer-by-brake and is one of the steering modes of tracked vehicles, but disadvantageous in wheeled vehicles as their regular steering mechanism is rendered ineffective by the effect. Given the above, the invention aims to improve utilization of said brakes to effect not only a desired brake parameter, e.g. braking torque, but to do so taking into account specific needs of electric vehicles. This is achieved by a method and a braking system according to the independent claims. The problem is solved by a method for controlling a multitude of braking devices of a vehicle to effect a desired brake function quantified as a desired brake parameter, wherein each of the braking devices is controllable by an actuation parameter to effect at least a portion of said desired brake function. The method comprises the steps of: determining, for each braking device, a brake capability representing a maximum brake function achievable with the braking device; determining, for each braking device, an actuation priority, wherein the actuation priority is determined from at least one predetermined operating parameter of the braking device and/or the vehicle; in order from highest priority to lowest priority of the braking devices; allocating, to each braking device, the actuation parameter, wherein the actuation parameter is chosen between the brake capability and the quantity of the desired brake parameter not yet allocated to other braking devices, whichever is lower. In this way, brakes that are more desirable to use in a particular braking situation are preferentially utilized as they have a higher priority. In this way, preferred braking devices can be used before other, less preferred, braking devices. In further embodiments, the desired brake parameter, the maximum actuation parameter and/or the actuation parameter each are expressed as one of the following: a torque, a force, a retardation. These kinds of parameters are easily measurable and available as inputs and/or outputs of braking devices, brakes and/or sensors. In further embodiments, when determining the actuation priority, braking devices comprising a non-frictional brake are determined to have a higher priority than braking devices comprising frictional brakes. Preferring non-frictional brakes allows for better longevity of frictional brake devices as this kind of brake device deteriorates through use. In further embodiments, when determining the actuation priority, braking devices comprising regenerational brakes are determined to have a higher priority than braking devices comprising dissipational brakes. In particular for electric vehicles, regenerating some electric energy from a braking action allows the electric vehicles to cover larger distances before requiring a recharge. In further embodiments, when determining the actuation priority, the higher the regeneration efficiency is of regenerational brake devices, the higher its priority will be relative to other braking devices comprising regenerational brakes. In this way, higher regeneration efficiency of a braking device will lead to that braking device being used preferentially. In further embodiments, when determining the actuation priority, one or more of the following parameters is taken into account: type or types of braking comprised in the braking devi