Limiting a Control Variable for a Motor of an Electric Power Steering System

A method for limiting a control variable for a motor of an electric power steering system for a motor vehicle with automated transverse guidance, the method comprising the steps of:

• receiving a setpoint steering angle;
• determining the control variable in accordance with the setpoint steering angle;
• receiving an actual steering angle;
• determining a virtual torsion-bar torque in accordance with the setpoint steering angle and the actual steering angle;
• determining at least one limiting value for the control variable in accordance with the virtual torsion-bar torque;
• and
• limiting the control variable in accordance with the at least one limiting value.

An apparatus for limiting a control variable for a motor of an electric power steering system for a motor vehicle with automated transverse guidance, comprising:

• a control unit configured so as to:
• receive a setpoint steering angle,
• determine the control variable in accordance with the setpoint steering angle,
• receive an actual steering angle,
• determine a virtual torsion-bar torque in accordance with the setpoint steering angle and the actual steering angle,
• determine at least one limiting value for the control variable in accordance with the virtual torsion-bar torque, and
• limit the control variable in accordance with the at least one limiting value.