A method for determining the rotor position of a three-phase drive, operated with a frequency converter, comprising the following steps: a) providing motor currents in stator coordinates (i α, i β) as a first input value to a first computing unit, b) determining motor set point voltages in stator coordinates from a current intermediate circuit voltage of the frequency converter and PWM signals (S 1 - S 6) as well as providing the motor set point voltages in stator coordinates as a second input value of the first computing unit, c) calculating the rotor position (φ) in stator coordinates, wherein - based on the general voltage equation u _ s s = R s ⋅ i _ s s + L s ⋅ d i _ s s dt + ω ⋅ ψ _ s s of the induction machine in space vector representation, a division into the two voltage-space vector components u α s = R s ⋅ i α s + L 0 ⋅ di α s dt + L 1 ⋅ di α s dt ⋅ cos 2 φ + di β s dt ⋅ sin 2 φ + L dq ⋅ di β s dt ⋅ cos 2 φ − di α s dt ⋅ sin 2 φ − ω ⋅ ψ β s − ω ⋅ L dq ⋅ i α s ⋅ cos 2 φ + i β s ⋅ sin 2 φ + ω ⋅ L 1 ⋅ i β s ⋅ cos 2 φ − i α s ⋅ sin 2 φ + ω ⋅ L 0 ⋅ i β s u β s = R s ⋅ i β s + L 0 ⋅ di β s dt − L 1 ⋅ di β s dt ⋅ cos 2 φ − di α s dt ⋅ sin 2 φ + L dq ⋅ di α s dt ⋅ cos 2 φ + di β s dt ⋅ sin 2 φ + ω ⋅ ψ α s + ω ⋅ L dq ⋅ i β s ⋅ cos 2 φ − i α s ⋅ sin 2 φ + ω ⋅ L 1 ⋅ i α s ⋅ cos 2 φ + i β s ⋅ sin 2 φ − ω ⋅ L 0 ⋅ i α s is carried out, - the voltage set point space vector u α s u β s and the current actual value space vector (i α, i β) are converted into a linear system with complex-valued input and output values, characterized in that - using the input values of the first computing unit, the rotor position (φ) is determined as the output value of this system by means of a linear regression analysis. a) providing motor currents in stator coordinates (i α, i β) as a first input value to a first computing unit, b) determining motor set point voltages in stator coordinates from a current intermediate circuit voltage of the frequency converter and PWM signals (S 1 - S 6) as well as providing the motor set point voltages in stator coordinates as a second input value of the first computing unit, c) calculating the rotor position (φ) in stator coordinates, wherein - based on the general voltage equation u _ s s = R s ⋅ i _ s s + L s ⋅ d i _ s s dt + ω ⋅ ψ _ s s of the induction machine in space vector representation, a division into the two voltage-space vector components u α s = R s ⋅ i α s + L 0 ⋅ di α s dt + L 1 ⋅ di α s dt ⋅ cos 2 φ + di β s dt ⋅ sin 2 φ + L dq ⋅ di β s dt ⋅ cos 2 φ − di α s dt ⋅ sin 2 φ − ω ⋅ ψ β s − ω ⋅ L dq ⋅ i α s ⋅ cos 2 φ + i β s ⋅ sin 2 φ + ω ⋅ L 1 ⋅ i β s ⋅ cos 2 φ − i α s ⋅ sin 2 φ + ω ⋅ L 0 ⋅ i β s u β s = R s ⋅ i β s + L 0 ⋅ di β s dt − L 1 ⋅ di β s dt ⋅ cos 2 φ − di α s dt ⋅ sin 2 φ + L dq ⋅ di α s dt ⋅ cos 2 φ + di β s dt ⋅ sin 2 φ + ω ⋅ ψ α s + ω ⋅ L dq ⋅ i β s ⋅ cos 2 φ − i α s ⋅ sin 2 φ + ω ⋅ L 1 ⋅ i α s ⋅ cos 2 φ + i β s ⋅ sin 2 φ − ω ⋅ L 0 ⋅ i α s is carried out, - the voltage set point space vector u α s u β s and the current actual value space vector (i α, i β) are converted into a linear system with complex-valued input and output values, characterized in that - using the input values of the first computing unit, the rotor position (φ) is determined as the output value of this system by means of a linear regression analysis. - based on the general voltage equation u _ s s = R s ⋅ i _ s s + L s ⋅ d i _ s s dt + ω ⋅ ψ _ s s of the induction machine in space vector representation, a division into the two voltage-space vector components u α s = R s ⋅ i α s + L 0 ⋅ di α s dt + L 1 ⋅ di α s dt ⋅ cos 2 φ + di β s dt ⋅ sin 2 φ + L dq ⋅ di β s dt ⋅ cos 2 φ − di α s dt ⋅ sin 2 φ − ω ⋅ ψ β s − ω ⋅ L dq ⋅ i α s ⋅ cos 2 φ + i β s ⋅ sin 2 φ + ω ⋅ L 1 ⋅ i β s ⋅ cos 2 φ − i α s ⋅ sin 2 φ + ω ⋅ L 0 ⋅ i β s u β s = R s ⋅ i β s + L 0 ⋅ di β s dt − L 1 ⋅ di β s dt ⋅ cos 2 φ − di α s dt ⋅ sin 2 φ + L dq ⋅ di α s dt ⋅ cos 2 φ + di β s dt ⋅ sin 2 φ + ω ⋅ ψ α s + ω ⋅ L dq ⋅ i β s ⋅ cos 2 φ − i α s ⋅ sin 2 φ + ω ⋅ L 1 ⋅ i α s ⋅ cos 2 φ + i β s ⋅ sin 2 φ − ω ⋅ L 0 ⋅ i α s is carried out, - the voltage set point space vector u α s u β s and the current actual value space vector (i α, i β) are converted into a linear system with complex-valued input and output values, characterized in that - using the input values of the first computing unit, the rotor position (φ) is determined as the output value of this system by means of a linear regression analysis.