DE102009056677B4 - Method and device for adapting a steering feel - Google Patents

Abstract

Method for adapting a steering feel of an electromechanical steering system (1) to a changing supply voltage (U), a first control unit (6) calculating a setpoint torque (T) of a unit for generating an assist torque (T) as a function of at least one input variable, wherein a second control unit (10) sets the assist torque (T) as a function of at least the setpoint torque (T) and the supply voltage (U), a compensation unit (8) determining at least one setting parameter at least as a function of the supply voltage (U), the setpoint torque (T) is adjusted as a function of the at least one setting parameter, characterized in that the compensation unit (8) also determines the at least one setting parameter as a function of a manual torque (TH).

Description

The invention relates to a method and a device for adapting a steering feel of an electromechanical steering to a changing supply voltage according to the preambles of claims 1 and 8.

In electromechanical steering systems, a servo motor usually applies a support torque to a steering rack or a steering column in order to make it easier to steer a motor vehicle. The servo motor draws electrical power to generate the assist torque. For this purpose, the servo motor is connected to a supply voltage, usually an on-board electrical system voltage of the motor vehicle. Changes in the supply voltage, in particular deviations of the on-board electrical system voltage from a reference voltage, also have an effect on the support torque generated by the servo motor. Changes in the supply voltage therefore influence a steering feel or steering behavior of the electromechanical steering. In particular, it can happen that with a supply voltage that is lower than a reference voltage, the support torque is reduced in such a way that the steering feel of the electromechanical steering changes. A changing steering feel of the electromechanical steering can lead to irritation of a motor vehicle driver, as a result of which undesirable driving conditions can occur. The steering feel is understood here as a torque that can be sensed haptically by the motor vehicle driver, for example on a steering wheel.

As a rule, an assist torque generated by the servo motor is controlled or regulated depending on the supply voltage in such a way that only minimal or no changes in the steering feel occur. Here, a motor control or motor control sets an assist torque as a function of the supply voltage. This can also be called voltage compensation at the motor level. The disadvantage here is that voltage compensation at the engine level is generally roughly designed and, particularly in the case of small hand torques applied by the motor vehicle driver, can still lead to changes in the steering feel of the electromechanical steering. Here, the manual torque denotes a torque applied by the motor vehicle driver, for example by means of the steering wheel, in order to bring about desired steering movements of the motor vehicle.

The EP 1 511 665 B1 discloses a motor vehicle electrical system with a dynamic, safety-relevant high-current consumer, which comprises a sensor system for detecting an input variable, a control device for generating an actuating signal and an actuator for converting the actuating signal into an output variable. The high-current consumer is assigned a device for detecting the voltage level of the vehicle electrical system. Their data are available locally to the control unit, the control unit comprising means with which the parameters of the actuator are adapted in the generation of the control signal in such a way that a voltage drop in the vehicle electrical system voltage is avoided. For this purpose, at least one limit is assigned to the voltage level of the vehicle electrical system. Means are also provided which limit the maximum current consumption and the maximum current gradient of the actuator when the voltage falls below a first limit value of the on-board electrical system voltage by adapting the parameters in such a way that the high-current consumer is switched off in stages without completely switching it off. The publication thus discloses a method which, in the event of a decreasing on-board network voltage, switches off the high-current consumer in stages. The high current consumer can be an electromechanical steering system. When the electromechanical steering system is switched off, however, the steering feel of the electromechanical steering system is influenced.

The DE 101 17 059 B4 discloses a vehicle that includes a variable ratio steering device and power steering. The steering device acts with a variable ratio on a steering system of the vehicle and changes the ratio of the steering angle of the steerable road wheels to a steering angle of the steering wheel by operating an electric motor according to the vehicle speed and the power steering acting on a steering system of the vehicle. The power steering provides assist steering torque by operating an electric motor in accordance with a manually applied steering wheel torque. The vehicle includes: a supply voltage measuring device for determining a voltage of a current source; and a control unit for controlling the electric motor of the steering device with variable transmission according to the determined voltage. When the detected voltage drops to a predetermined voltage or below, the control unit brings the variable gear steering device into a slow state and then shuts down the variable gear steering device. Here, too, a steering feel of the steering device is influenced when the voltage drops.

• einen Kraftdetektor, der auf die Vorrichtung aufgebrachte Kräfte erkennt, wobei die aufgebrachten Kräfte die Betätigungskraft seitens des Fahrers enthalten;
• einen Rechner, der einen Steuerbetrag berechnet, der die Unterstützungskraft an die Vorrichtung gibt, basierend auf Ergebnissen, die von dem Kraftdetektor erkantn worden sind, wobei der Steuerbetrag für jeden Tüy der aufgebrachten Kräfte berechnet wird, deren Frequenzbänder zumindest teilweise unterschiedlich zueinander sind;
• einen Treiber, der den Unterstützungsmechanismus basierend auf dem vom Rechner berechneten Steuerbetrag betreibt;
• einen Batteriezustandsdetektor, der einen Betriebszustand der Batterie erkennt; und einen Einsteller, der den Steuerbetrag so einstellt, dass, wenn der berechnete Batteriezustand bei einer Energieversorgungsfunktion seitens der Batterie abnimmt, der Steuerbetrag einer spezifizierten Kraft aus den angelegten Kräften mit spezifizierten Frequenzkomponenten verringert wird.
• Die Vorrichtung ist beispielsweise eine Lenkung. Dabei berechnet ein Unterstützungsbetragsrechner in Abhängigkeit eines Handmoments und einer Fahrzeuggeschwindigkeit ein Sollmoment, das in Abhängigkeit eines Spannungsdetektors verändert wird.

From the generic DE 11 2007 002 144 T5 a controller for controlling a device installed in a vehicle is known, the device being a Has an operating member which is operated by a driver receiving an operating force from the driver, and has an assist mechanism which applies an assist force to the operating member, the assist mechanism being operated by a battery installed in the vehicle, the controller comprising:

• a force detector that detects forces applied to the device, the forces applied including the operator actuation force;
• a calculator that calculates a control amount that gives the assist force to the device based on results recognized by the force detector, the control amount being calculated for each tuy of applied forces whose frequency bands are at least partially different from each other;
• a driver that operates the support mechanism based on the tax amount calculated by the computer;
• a battery condition detector that detects an operating condition of the battery; and an adjuster that adjusts the control amount so that when the calculated battery state decreases in a power supply function on the part of the battery, the control amount of a specified force is reduced from the applied forces with specified frequency components.
• The device is, for example, a steering system. A support amount calculator calculates a target torque depending on a hand torque and a vehicle speed, which is changed depending on a voltage detector.

The technical problem arises of creating a method and a device for adapting a steering feel of an electromechanical steering system to a changing supply voltage, which allows a targeted adaptation of the steering feel to a changing supply voltage, in particular compensating for the effect of changes in the supply voltage on the Steering feeling, in particular during a steering process, that is to say with small hand torques applied by the motor vehicle driver.

The solution to the technical problem results from the features of independent claims 1 and 8. Further advantageous refinements of the invention result from the subclaims.

A method is proposed for adapting a steering feel of an electromechanical steering system to a changing supply voltage. The supply voltage is used for the voltage supply of a unit for generating an assist torque, in particular a servo motor. The supply voltage can be an on-board electrical system voltage of a motor vehicle. Depending on at least one input variable, a first control unit calculates a setpoint torque of the unit for generating an assist torque. The target torque can be set via a first calculation rule for the target torque. The first control unit can be, for example, a steering control device for electromechanical steering. The input variable can be at least one input variable from the group hand torque, steering angle, steering angle speed, rotor position sensor and other typical input variables. The rotor position here designates a position of a rotor of the servo motor. A manual torque can be recorded, for example, using a sensor for recording the manual torque. Analogous to the manual torque, the further input variables can also be recorded using sensors. A second control unit sets an assist torque of the unit to generate an assist torque depending on at least the target torque. The second control unit is, for example, a motor control device of the servo motor. Here, the second control unit can set the support torque by means of a regulation or a control. In addition to the target torque determined by the first control unit, the second control unit can also set the support torque as a function of the supply voltage. In the case of a predefined setpoint torque, for example, a current supplied to the unit for generating an assist torque is increased or decreased depending on the supply voltage in order to prevent the assist torque from falling or increasing. This can also be called voltage compensation at the motor level. In the case of voltage compensation at motor level, a change in the support torque is only caused by a change in the supply voltage, not by a change in the setpoint torque.

According to the invention, a compensation unit determines at least one setting parameter at least as a function of the supply voltage. The compensation unit can be designed as a separate control unit or as part of, for example, the steering control device. The compensation unit determines the at least one setting parameter according to a predetermined calculation rule for the setting parameter. The calculation rule for the setting parameter can be a linear or non-linear calculation rule for the setting parameter. It is also conceivable that the calculation rule for the Setting parameters or parameters of the calculation rule for the setting parameters are changeable, for example programmable. For this purpose, the compensation unit can have a programming interface. Characteristics of the voltage compensation, for example in accordance with a request of the motor vehicle driver, can hereby be set in an advantageous manner. The setpoint torque calculated by the first control unit is adjusted as a function of the at least one setting parameter. Depending on the at least one setting parameter, the target torque can be reduced, increased or kept constant. The target torque can be adjusted via an addition and / or a multiplication and / or via a further calculation rule for the target torque. The further calculation rule can be a linear or non-linear calculation rule. The adaptation of the target torque as a function of the at least one setting parameter can be referred to as voltage compensation at the steering function level. Here, a steering function level denotes a functional level of electromechanical steering in which steering system-specific state variables, for example the previously mentioned input variables of the first control unit, are evaluated in order to generate a desired steering feel of the electromechanical steering. The steering function level is arranged hierarchically above the engine level. A change (adaptation) of the target torque also changes the support torque generated by the unit for generating a support torque and thereby an support torque applied to a steering rack of the electromechanical steering. Since the steering rack is mechanically coupled to a steering wheel, for example via a steering column, this results in a change in the steering feel of the electromechanical steering.

In this case, the supply voltage can be detected, for example, by a sensor for detecting the supply voltage and can be transmitted to the compensation unit and / or the second control unit in terms of data technology.

The method according to the invention advantageously provides the possibility of specifically adapting the steering feel to a changing supply voltage. The supply voltage can be greater or less than a reference voltage, for example. There is also an improved voltage compensation at low hand torques. Especially at low hand torques, voltage compensation at the motor level is too rough. In the case of pure voltage compensation at the motor level, an assist torque is therefore adapted in the event of a changing supply voltage in such a way that short-term changes in the steering feel of the electromechanical steering continue to occur. This is disadvantageous in particular in the area of low hand torques, which are applied by the motor vehicle driver, for example by means of a steering wheel. According to the invention, it is thus advantageous that even in the area of small hand torques, the steering torque of the electromechanical steering can be changed only minimally or not by adjusting the target torque. A changing supply voltage also results when a recuperation operation of an electric or hybrid vehicle is activated or deactivated. A changing supply voltage can also result in the recuperation mode of the electric or hybrid vehicle. The method according to the invention can advantageously be used to adapt the steering feel even in recuperation mode and / or when activation of recuperation mode and / or deactivation of recuperation mode of the electric or hybrid vehicle.

The at least one setting parameter is additionally determined as a function of a hand torque. The manual torque here denotes a torque applied by the motor vehicle driver to the steering column, for example by means of a steering wheel. The manual torque can be recorded, for example, using a sensor for detecting the manual torque. In particular with higher hand torques, the sensitivity of the motor vehicle driver to a steering feeling of the electromechanical steering is reduced. For the motor vehicle driver, therefore, changes in the supply voltage in the case of low hand torques produce a greater change in the steering feel, in particular haptically detectable by the motor vehicle driver, than in the case of higher hand torques. Voltage compensation at the steering function level is therefore preferred to be carried out at low hand torques. The proposed method can therefore be used to carry out voltage compensation at the steering function level with low hand torques, in particular during a steering process. Here, the at least one setting parameter can be calculated by means of a calculation rule for the setting parameter, which specifies a relationship between the at least one setting parameter and the manual torque or a relationship between the at least one setting parameter and the two variables manual torque, supply voltage.

bestimmen. Hierbei bezeichnet ΔU die Differenz, U die Versorgungsspannung und U_ref die Referenzspannung.In one embodiment, the at least one setting parameter is additionally determined as a function of a reference voltage, the at least one setting parameter being determined as a function of a difference between the supply voltage and reference voltage such that the Target torque is reduced or increased or not adjusted. This advantageously results in a steering feel of the electromechanical steering being adapted if the supply voltage deviates from a reference state, that is to say the reference voltage. The reference voltage can be, for example, a reference voltage of the vehicle electrical system, for example 14V. A difference can vary, for example $$\Delta \text{U}=\text{U}-{\text{U}}_{\text{ref}}$$

determine. Inscribed here ΔU the difference, U the supply voltage and U _ref the reference voltage.

In a further embodiment, the setpoint torque is reduced when there is a positive difference between the supply and reference voltages and increased when there is a negative difference between the supply and reference voltages. With a supply voltage that is higher than the reference voltage, it can happen that an assist torque of the unit for generating an assist torque increases briefly before it is adjusted to the setpoint torque again, for example by voltage compensation at the motor level. Analogously, with a supply voltage that is lower than the reference voltage, the support torque may decrease briefly before it is adjusted to the setpoint torque again, for example by voltage compensation at the motor level. By reducing the setpoint torque for a positive difference between supply and reference voltage and increasing the setpoint torque for a negative difference between supply and reference voltage, it is advantageously avoided that changes in the supply voltage with respect to the reference voltage affect the generated support torque and thus that Affect the steering feel of the electromechanical steering. The setpoint torque can also only be adjusted in a predetermined interval of the difference between supply voltage and reference voltage. The interval can have a lower voltage limit and an upper voltage limit. A lower voltage limit can be, for example, ΔU = -2V and an upper voltage limit can be ΔU = 2V. If the difference between supply voltage and reference voltage is smaller than the lower voltage limit, the compensation unit can determine the at least one setting parameter as a first predetermined setting parameter. Analogously, the compensation unit can determine the at least one setting parameter as a second predetermined setting parameter if the difference between supply voltage and reference voltage is greater than the upper voltage limit.

In a further embodiment, the at least one setting parameter for at least one interval of the supply voltage is linearly dependent on the supply voltage or linearly dependent on a difference between supply and reference voltage. Through a linear dependency of the at least one setting parameter on the supply voltage or a difference between supply and reference voltage, a simple determination of the at least one setting parameter can advantageously be achieved by means of the compensation unit. For example, it is conceivable that the at least one setting parameter is linearly dependent on the supply voltage in an interval of the supply voltage of 12V to 16V. Below 12V, the at least one setting parameter can be determined as a predetermined setting parameter, for example as the first predetermined setting parameter. Above 16V, the at least one setting parameter can be determined in an analogous manner as a predetermined setting parameter, for example the second predetermined setting parameter. If a reference voltage is 14V, for example, then the at least one setting parameter is linearly dependent, for example, in an interval of -2V to 2V, depending on the difference between the supply voltage and the reference voltage.

In a preferred embodiment, the at least one setting parameter is determined as a function of the hand torque in such a way that the setpoint torque is reduced as the hand torque increases and / or is increased as the hand torque decreases. This advantageously results in that voltage compensation at the steering function level is preferably carried out during a pivoting operation.

In a further embodiment, the at least one setting parameter is determined as a function of the hand torque in such a way that the desired torque decreases exponentially or linearly as the hand torque increases. This advantageously results in a steady and no sudden change in the steering feel for the motor vehicle driver and thus an improved steering property of the electromechanical steering.

In a further embodiment, the at least one setting parameter is determined as a function of the hand torque in such a way that the target torque is reduced from a first predetermined threshold value of the hand torque. This advantageously has the result that a simple threshold-dependent adaptation of the target torque to the manual torque is possible.

A device for adapting a steering feel of an electromechanical steering system to a changing one is also proposed Supply voltage. The device comprises at least a first control unit, a unit for generating an assist torque and a second control unit. A setpoint torque of the unit for generating an assist torque can be calculated using the first control unit as a function of at least one input variable. The second control unit can be used to set an assist torque as a function of at least the target torque and a supply voltage. The device further comprises a compensation unit. The compensation unit can be used to determine at least one setting parameter at least as a function of the supply voltage. The setpoint torque can also be adjusted as a function of the at least one setting parameter.

The device comprises at least one unit for detecting a supply voltage and at least one unit for detecting a manual torque, the compensation unit also being able to determine the at least one setting parameter as a function of the manual torque.

With the proposed device, one of the previously described methods can advantageously be carried out.

• 1 ein schematisches Blockschaltbild einer elektromechanischen Lenkung,
• 2 ein schematisches Blockschaltbild einer Spannungskompensation,
• 3 ein schematisches Blockschaltbild einer Vorrichtung zur Anpassung eines Lenkgefühls,
• 4 eine beispielhafte Berechnungsvorschrift für einen Einstellparameter und
• 5 eine weitere beispielhafte Berechnungsvorschrift für einen Einstellparameter.

The invention is explained in more detail using an exemplary embodiment. The figures show:

• 1 1 shows a schematic block diagram of an electromechanical steering,
• 2nd 1 shows a schematic block diagram of a voltage compensation,
• 3rd 1 shows a schematic block diagram of a device for adapting a steering feel,
• 4th an exemplary calculation rule for a setting parameter and
• 5 another exemplary calculation rule for a setting parameter.

In the following, the same reference symbols designate elements with the same or similar technical properties.

1 shows an electromechanical steering 1 of a motor vehicle, not shown. The electromechanical steering 1 includes a steering wheel 2nd , using the steering wheel 2nd a hand moment T _H on a steering column 3rd is applicable. Electromechanical steering is also included 1 a sensor 4th for detecting a steering angle and a sensor 5 to record the hand torque T _H . Electromechanical steering is also included 1 a first control unit 6 , wherein the first control unit 6 a target torque T _should depending on a vehicle speed v , a steering angle and that of the sensor 5 to record the hand torque T _H captured hand torque T _H calculated. The vehicle speed v can be from a sensor 7 to record the vehicle speed v be recorded. The electromechanical steering 1 further comprises a compensation unit 8th . The compensation unit 8th calculated depending on the hand torque T _H and a supply voltage U an additional moment T _add . The supply voltage U is done by a sensor 9 to detect the supply voltage U detected. That from the compensation unit 8th certain additional moment T _add is on that from the first control unit 6 calculated target torque T _should added. The sum of the target torque T _should and the additional moment T _add becomes a second control unit 10th supplied as an input variable. The second control unit 10th is a motor control unit of a servo motor 11 . Next is the second control unit 10th also the supply voltage U supplied as an input variable. Depending on the sum of the target torque T _should and the additional moment T _add and the supply voltage U represents the second control unit 10th a moment of support T _supp of the servo motor 11 a. The servo motor 11 is about a gearbox 12 with a steering rack 13 connected. Using the steering rack 13 are steerable wheels of the motor vehicle, not shown, steerable. That from the servo motor 11 by means of the transmission 12 on the steering rack 13 applied support torque affects a steering feel of the motor vehicle. Via a gear, not shown, between the steering column 3rd and the steering rack 13 becomes the assist torque from the servo motor 11 is generated, can also be haptically detected by a motor vehicle driver. By means of the electromechanical steering shown 1 a voltage-dependent change in steering feel can therefore be carried out.

2nd shows a schematic block diagram of a voltage compensation. The sensor 9 to detect the supply voltage U detects the supply voltage U and transmits this data technology to the second control unit 10th and a steering control device 14 . The steering control unit 14 includes the compensation unit 8th and the first control unit 6 . The first control unit 6 determines a target torque T _should , the compensation unit 8th the additional moment T _add from the steering control unit 14 added and to the second control unit 10th be transmitted. Depending on the sum of the target torque T _should and the additional moment T _add and the supply voltage U represents the second control unit 10th a moment of support T _supp of the servo motor 11 a.

3rd shows a further schematic block diagram of a device for adapting a steering feel of the electromechanical steering 1 . The steering control unit 14 includes a compensation unit 8th and the first control unit 6 . The compensation unit 8th calculated depending on the supply voltage U and the hand moment T _H a setting parameter, the additional torque in this embodiment T _add is. Depending on the hand torque T _H , the vehicle speed v and the additional torque T _add calculates the first control unit 6 the target torque T _should for the servo motor 11 . The second control unit 10th includes an adaptation unit 15 that performs voltage compensation at the motor level. The second control unit also includes 10th one unity 16 for motor control, which depends on the adaptation unit 15 calculated support torque T _supp the servo motor 11 regulates.

4th shows an exemplary calculation rule 17th of the additional torque T _add from the supply voltage U . 4th shows the calculation rule 17th for the setting parameter of the compensation unit 8th , here the additional moment T _add . The calculation rule 17th for the setting parameter is shown as a thick line. Here, a reference voltage Uref is 14V. In a range of supply voltage U from 12V to 16V is the additional torque T _add linear depending on the supply voltage U . It is shown here that the additional torque T _add is positive at the supply voltage of 12V and a first predetermined value Tmax _add assumes. The additional moment T _add decreases linearly with increasing supply voltage U from. The slope of the linear relationship between the additional moment T _add and the supply voltage U is selected in such a way that the additional torque T _add a value of 0 for the reference voltage Uref and for a supply voltage U of 16V a second predetermined value Tmin _add assumes the second predetermined value Tmin _add is negative. Is the supply voltage U less than 12V, so is the additional torque T _add fixed to the first predetermined value Tmax _add set and no longer changes linearly with falling supply voltage U . Is the supply voltage U the additional torque is greater than 16V T _add fixed to the second predetermined value Tmin _add set and no longer changes linearly with increasing supply voltage U .

5 shows a further calculation rule for a setting parameter, here again the additional torque T _add . The additional moment T _add becomes dependent on the supply voltage U and the hand moment T _H certainly. The first calculation rule 17th corresponds to that in 4th calculation rule shown 17th . Using the first calculation rule 17th becomes a provisional additional moment T _add ' calculated. Using a second calculation rule 18th becomes the hand moment T _H a factor F calculated. The additional moment T _add results from a multiplication of the provisional additional torque T _add ' with the factor F . In 5 is shown that the second calculation rule 18th has an exponential course, the factor F with increasing hand torque T _H decreased. This advantageously suppresses the additional torque T _add at higher hand moments T _H .

Reference symbol list

1

Electric Power Steering

2nd

steering wheel

3rd

Steering column

4th

Steering angle sensor

5

Hand torque sensor

6

first control unit

7

Vehicle speed sensor

8th

Compensation unit

9

Sensor for detecting a supply voltage

10th

second control unit

11

Servo motor

12

transmission

13

Steering rack

14

Steering control unit

15

Adaptation unit

16

Motor control unit

17th

Calculation rule, first calculation rule

18th

second calculation rule

U

Supply voltage

v

Vehicle speed

T _H

Hand moment

T _should

Target torque

T _add

Additional moment

T _add '

provisional additional moment

Tmax _add

first predetermined value of the additional torque

Tmin _add

second predetermined value of the additional torque

T _supp

Support moment

U _ref

Reference voltage

F

factor

ΔU

Difference between supply and reference voltage

Claims (8)

A method for adapting a steering feeling of an electromechanical steering system (1) to a changing supply voltage (U), wherein a first control unit (6) in response to at least one input variable, a target torque (T _soll) to a unit for generating an assist torque (T _supp) is calculated, wherein a second control unit (10) sets the support torque (T _supp ) depending on at least the target torque (T _soll ) and the supply voltage (U), a compensation unit (8) determining at least one setting parameter at least depending on the supply voltage (U), whereby the target torque (T _soll) in dependence on the at least one adjustment parameter is adjusted, characterized in that the compensation unit (8) at least one setting parameter determines the additional function of a manual torque (TH). Procedure according to Claim 1 , characterized in that the at least one setting parameter is additionally determined as a function of a reference voltage (U _ref ), the at least one setting parameter being determined as a function of a difference (ΔU) between supply and reference voltage (U, Uref) such that the setpoint torque (T _Soll ) is reduced or increased or not adjusted. Procedure according to Claim 2 , characterized in that the setpoint torque (T _soll ) is reduced in the case of a positive difference (ΔU) between the supply and reference voltages (U, U _ref ) and increased in the case of a negative difference (ΔU) between the supply and reference voltages (U, U _ref ). Procedure according to one of the Claims 1 to 3rd , characterized in that the at least one setting parameter for at least one interval of the supply voltage (U) is linearly dependent on the supply voltage (U) or the difference (ΔU) between supply and reference voltage (U, Uref). Method according to one of the preceding claims, characterized in that the at least one adjustment parameter in dependence on the manual torque (TH) is determined such that the target torque (T _soll) is reduced with increasing manual torque (TH) and / or with decreasing manual torque (T _H) is increased. Procedure according to Claim 5 , characterized in that the at least one setting parameter is determined as a function of the hand torque (T _H ) in such a way that the desired torque (T _soll ) decreases exponentially or linearly as the hand torque (T _H ) increases. Procedure according to Claim 5 or 6 , characterized in that the at least one setting parameter is determined as a function of the hand torque (T _H ) in such a way that the target torque (T _soll ) is reduced from a first predetermined threshold value of the hand torque (T _H ). Device for adapting a steering feel of an electromechanical steering (1) to a changing supply voltage (U), the device comprising at least a first control unit (6), a unit for generating an assist _torque (T _supp ) and a second control unit (10), wherein by means of the first control unit (6), depending on at least one input variable, a setpoint torque (T _soll ) of the unit for generating the support torque (T _supp ) can be calculated, with the second control unit (10) the support _torque (T _supp ) depending on at least the target torque (T _soll) and the supply voltage (U) is adjustable, the apparatus further comprising a compensation unit (8), wherein by means of the compensation unit (8) at least one adjustment parameter is determined at least as a function of the supply voltage (U), said target torque ( T _soll ) is adaptable depending on the at least one setting parameter , dadurc h characterized in that the device comprises at least one sensor (9) for detecting the supply voltage (U) and at least one sensor (5) for detecting a manual torque (T _H ), the at least one setting parameter additionally being dependent on the compensation unit (8) of the hand torque (T _H ) can be determined.

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