Abstract: A method for the improved speed determination of electric motors while taking into account angle errors of an angular position sensor is provided. A commutation sensor based on a magnetic rotary encoder, the angle signal of which has an angle-dependent and thus periodic angle error, is used. By differentiation, this defective angle signal is converted into a raw speed signal, which has two disturbance components. One disturbance component results from the angle error and is the disturbance waviness, which is periodic similar to the angle error. The second disturbance component is formed by a noise component superposing the raw speed signal. In order to correct the defective raw speed signal, half of the period duration of the raw speed signal must be ascertained. If this half of the period duration is ascertained two samples of the raw speed signal lying exactly one half of the period duration of the raw speed signal apart from each other are averaged.

Abstract: A method of determining a corrected rotational speed signal for an electric motor, comprising determining a periodic rotational angle signal that has a periodic rotational angle error that is dependent on the rotational angle, determining a half period duration of an interference ripple of a raw rotational speed signal, averaging of at least one pair of sampled values of the raw rotational speed signal, converting a rotational angle signal to a digital raw rotational speed signal that includes an interference ripple, determining an average value in response to at least one pair of sampled values of the raw rotational speed signal, forming a correction value dependent on a sampling period duration and on a frequency of the interference ripple of the raw rotational speed signal for consideration of a discretization error, and forming the corrected rotational speed signal from a difference between the average value and the correction value.

Abstract: A rotor position encoder (01) for an electronically commutated electric machine (02) having a stator and a rotor (03) and including a rotor position sensor (05) which is mounted on the stator so as to rotate therewith and has the purpose of detecting the rotational position of the rotor (03) with respect to the magnetic field of the stator, and a signal encoder (07) which is mounted on the rotor (03) so as to rotate therewith. The rotor position encoder is defined in that it has a reference encoder (08) for detecting reference values of the magnetic flux density of the rotor field, wherein the reference values (09) serve to determine an angular offset (11) between the signal encoder (07) and the position of the rotor (03). Furthermore, a method for determining an angular offset (11) between a signal encoder (07) of a rotor position encoder (01) and a rotor position of an electronically commutated electric machine (02) is provided.

Abstract: A method of determining a corrected rotational speed signal for an electric motor, comprising determining a periodic rotational angle signal that has a periodic rotational angle error that is dependent on the rotational angle, determining a half period duration of an interference ripple of a raw rotational speed signal, averaging of at least one pair of sampled values of the raw rotational speed signal, converting a rotational angle signal to a digital raw rotational speed signal that includes an interference ripple, determining an average value in response to at least one pair of sampled values of the raw rotational speed signal, forming a correction value dependent on a sampling period duration and on a frequency of the interference ripple of the raw rotational speed signal for consideration of a discretization error, and forming the corrected rotational speed signal from a difference between the average value and the correction value.

Abstract: A sensor system (01) for measuring the rotational speed of a rotatable component having a pole wheel (02) comprising a carrier (04) with at least one path of alternating magnetic north and south poles (05), and at least one magnetic field sensor (03) for sampling the path of the pole wheel (02) is provided. The sensor system (01) provides that the rotational direction in front of and behind the magnetic field sensor (03) a ferromagnetic flux-conducting component (07) is arranged in each case opposite the path, the ferromagnetic flux-conducting components (07) being arranged in the installation space between the magnetic field sensor (03) and the pole wheel (02), the distance between the ferromagnetic flux-conducting components (07) corresponding to the width of one magnetic pole (05) of the pole wheel (02).

Abstract: A method for the improved speed determination of electric motors while taking into account angle errors of an angular position sensor is provided. A commutation sensor based on a magnetic rotary encoder, the angle signal of which has an angle-dependent and thus periodic angle error, is used. By differentiation, this defective angle signal is converted into a raw speed signal, which has two disturbance components. One disturbance component results from the angle error and is the disturbance waviness, which is periodic similar to the angle error. The second disturbance component is formed by a noise component superposing the raw speed signal. In order to correct the defective raw speed signal, half of the period duration of the raw speed signal must be ascertained. If this half of the period duration is ascertained two samples of the raw speed signal lying exactly one half of the period duration of the raw speed signal apart from each other are averaged.

Abstract: A sensor system (01) for measuring the rotational speed of a rotatable component having a pole wheel (02) comprising a carrier (04) with at least one path of alternating magnetic north and south poles (05), and at least one magnetic field sensor (03) for sampling the path of the pole wheel (02) is provided. The sensor system (01) provides that the rotational direction in front of and behind the magnetic field sensor (03) a ferromagnetic flux-conducting component (07) is arranged in each case opposite the path, the ferromagnetic flux-conducting components (07) being arranged in the installation space between the magnetic field sensor (03) and the pole wheel (02), the distance between the ferromagnetic flux-conducting components (07) corresponding to the width of one magnetic pole (05) of the pole wheel (02).

Abstract: A rotor position encoder (01) for an electronically commutated electric machine (02) having a stator and a rotor (03) and including a rotor position sensor (05) which is mounted on the stator so as to rotate therewith and has the purpose of detecting the rotational position of the rotor (03) with respect to the magnetic field of the stator, and a signal encoder (07) which is mounted on the rotor (03) so as to rotate therewith. The rotor position encoder is defined in that it has a reference encoder (08) for detecting reference values of the magnetic flux density of the rotor field, wherein the reference values (09) serve to determine an angular offset (11) between the signal encoder (07) and the position of the rotor (03). Furthermore, a method for determining an angular offset (11) between a signal encoder (07) of a rotor position encoder (01) and a rotor position of an electronically commutated electric machine (02) is provided.