Method for operating a permanent magnet synchronous motor, the operating parameters of which are specified in a two-dimensional d/q coordinate system, the method comprising the following steps: - receiving a torque request (Tm), - converting the torque request (Tm) into a first vector, the q coordinate of which corresponds to the torque request (Tm) and the d coordinate of which is zero, - representing a number of constraints as areas (1, 2, 3, 4) in the d/q coordinate system, each required area (1, 2, 3) representing a constraint such that an operational vector should lie within the required area (1, 2, 3), and each prohibited area representing a constraint such that an operational vector should lie outside the prohibited area, wherein the method is characterized in that it has the following steps: - checking whether the first vector lies within all of the required areas (1, 2, 3) and outside all of the prohibited areas, - if so, using the first vector as an operational vector, - if not: - determining respective highest q coordinates of the required areas (1, 2, 3), and reducing the q coordinate of the first vector to the lowest of the highest q coordinates of the required areas (1, 2, 3), thereby obtaining a second vector, - checking whether the second vector lies within a first required area, - if so, using the second vector as a third vector, - if not, changing the d coordinate of the second vector, so that it lies on a limitation of the first required area with the smallest amount of the d coordinate, thereby obtaining a third vector, - checking whether the third vector lies within a second required area, - if so, using the third vector as a fourth vector, - if not, changing the coordinates of the third vector along a change limitation up to the point of intersection between a limitation of the second required area with the change limitation with the highest q coordinate, thereby obtaining a fourth vector, - determining an operational vector on the basis of the fourth vector, - activating the permanent magnet synchronous motor by means of operational parameters that are indicated by the operational vector. - receiving a torque request (Tm), - converting the torque request (Tm) into a first vector, the q coordinate of which corresponds to the torque request (Tm) and the d coordinate of which is zero, - representing a number of constraints as areas (1, 2, 3, 4) in the d/q coordinate system, each required area (1, 2, 3) representing a constraint such that an operational vector should lie within the required area (1, 2, 3), and each prohibited area representing a constraint such that an operational vector should lie outside the prohibited area, wherein the method is characterized in that it has the following steps: - checking whether the first vector lies within all of the required areas (1, 2, 3) and outside all of the prohibited areas, - if so, using the first vector as an operational vector, - if not: - if so, using the first vector as an operational vector, - if not: - determining respective highest q coordinates of the required areas (1, 2, 3), and reducing the q coordinate of the first vector to the lowest of the highest q coordinates of the required areas (1, 2, 3), thereby obtaining a second vector, - checking whether the second vector lies within a first required area, - if so, using the second vector as a third vector, - if not, changing the d coordinate of the second vector, so that it lies on a limitation of the first required area with the smallest amount of the d coordinate, thereby obtaining a third vector, - if so, using the second vector as a third vector, - if not, changing the d coordinate of the second vector, so that it lies on a limitation of the first required area with the smallest amount of the d coordinate, thereby obtaining a third vector, - checking whether the third vector lies within a second required area, - if so, using the third vector as a fourth vector, - if not, changing the coordinates of the third vector along a change limitation up to the point of intersection between a limitation of the second required area with the change limitation with the highest q coordinate, thereby obtaining a fourth vector, - if so, using the third vector as a fourth vector, - if not, changing the coordinates of the third vector along a change limitation up to the point of intersection between a limitation of the second required area with the change limitation with the highest q coordinate, thereby obtaining a fourth vector, - determining an operational vector on the basis of the fourth vector, - activating the permanent magnet synchronous motor by means of operational parameters that are indicated by the operational vector.