A rotor for an electrical machine excited by permanent magnets, comprising - a substantially cylindrical magnetic body of the rotor fitted onto the shaft of the electrical machine, - a set of permanent magnets (18, 20) used to create a first pole and a second pole alternately in the circumferential direction, the set of permanent magnets (18, 20) comprising first and second magnets, the first and second magnets being respectively excited in opposite directions (N, S) and fitted in openings (12, 14) arranged within the rotor, the distance between the openings (12, 14) at the end facing the circumference of the rotor being substantially equal around the rotor, - a body part with several segments arranged in the circumferential direction and extending to the outer circumference of the rotor, said segments having an outer side forming the outer circumference of the rotor and - several sections each arranged between segments, wherein - said segments form the first pole and the sections form the second pole, - the first and second permanent magnets (18, 20) are arranged between each section and segment on the side edges of the sections, - said segments have side edges constituting an equal acute angle with the outer side, whereby the sections are created tapered outwards in the radial direction of the rotor such that the first and second permanent magnets (18, 20) on the side edges of the sections are slanted in relation to each other in the radial direction of the rotor, these permanent magnets (18, 20) being closer to each other at the end facing the outer circumference of the rotor compared to the end facing the shaft of the electrical machine, making the second pole tapered outwards, and - the second pole has a third permanent magnet located between the ends of the first and second permanent magnets (18, 20) of this pole on the edge facing the shaft. - a substantially cylindrical magnetic body of the rotor fitted onto the shaft of the electrical machine, - a set of permanent magnets (18, 20) used to create a first pole and a second pole alternately in the circumferential direction, the set of permanent magnets (18, 20) comprising first and second magnets, the first and second magnets being respectively excited in opposite directions (N, S) and fitted in openings (12, 14) arranged within the rotor, the distance between the openings (12, 14) at the end facing the circumference of the rotor being substantially equal around the rotor, - a body part with several segments arranged in the circumferential direction and extending to the outer circumference of the rotor, said segments having an outer side forming the outer circumference of the rotor and - several sections each arranged between segments, - said segments form the first pole and the sections form the second pole, - the first and second permanent magnets (18, 20) are arranged between each section and segment on the side edges of the sections, - said segments have side edges constituting an equal acute angle with the outer side, whereby the sections are created tapered outwards in the radial direction of the rotor such that the first and second permanent magnets (18, 20) on the side edges of the sections are slanted in relation to each other in the radial direction of the rotor, these permanent magnets (18, 20) being closer to each other at the end facing the outer circumference of the rotor compared to the end facing the shaft of the electrical machine, making the second pole tapered outwards, and - the second pole has a third permanent magnet located between the ends of the first and second permanent magnets (18, 20) of this pole on the edge facing the shaft.