A controller (1) to reduce integral non-linearity errors of a magnetic rotary encoder (2) comprises a position error determining unit (20) to determine a plurality of time marks (P0, . . . , Pk) specifying a respective time at which a moving device (3) reaches a respective one of predefined positions (α0, . . . , αk). The position error determining unit (20) calculates a plurality of error correction parameters (B[0], . . . , B[k]) in dependence on the time marks (P0, . . . , Pk). An error compensation unit (10) of the controller determines a respective error compensated position parameter (φ.sub.start.sub._comp, φ0_comp, . . . , φn_comp) for each position parameter (φ.sub.start, φ0, . . . , φn) received from the encoder (2) in dependence on the respective position parameter (φ.sub.start, φ0, . . . , φn) and the respective error correction parameter (B[0], . . . , B[k]).

In a position detector for converting, into position information, two signals shifted in phase by 90 degrees from each other, a phase correction value calculator for calculating a phase correction value for correcting a phase difference between the two signals calculates a phase change value representing a change in the phase correction value, to find a next phase correction value based on the phase change value and a present phase correction value. A virtual change value calculator calculates, based on second-order components obtained by Fourier analysis of a radius value, a virtual phase change value representing another change in the phase correction value obtained when changes in offset and amplitude ratio are ignored, and a virtual amplitude change value representing a change rate in an amplitude ratio correction value obtained when a change in the phase difference is ignored.

A magnetic field sensor includes at least one magnetic field sensing element configured to generate a measured magnetic field signal responsive to an external magnetic field and to generate a reference magnetic field signal responsive to a reference magnetic field and a calibration circuit configured to divide the measured magnetic field signal by the reference magnetic field signal to generate a calibrated magnetic field signal. The calibrated signal has reduced susceptibility to stress influences.

An angle sensor includes a detection signal generation unit for generating detection signals, and an angle detection unit for generating a detected angle value on the basis of the detection signals. The angle detection unit includes a signal conversion unit for performing a conversion operation, and an angle operation unit for performing an angle operation. The conversion operation is to convert the detection signals into first and second operation signals. The angle operation is to calculate the detected angle value using the first and second operation signals. The conversion operation includes an operation using a correction-term-containing function Which contains a correction term for reducing a first error or a second error occurring in the detected angle value. When the angle to be detected varies with a predetermined period, the first error varies with the predetermined period, whereas the second error varies with a period ½ the predetermined period.

A position sensing device for measuring a position, comprises a position sensing device for measuring a position; a plurality of sensors arranged to produce sense signals each being a function of an input phase representative of a position to be measured; a combiner circuit arranged to generate an error signal by combining the sense signals according to an array of weight factors; a processing block including a loop filter to filter the error signal and arranged to output a phase value representative of the position; and a feedback loop comprising a feedback signal unit arranged for receiving the output phase value and for adjusting based on the received output phase value of the array of weight factors.

Systems and methods for sensor position measurements are provided. Aspects include receiving, through a first signal path, a first secondary signal from a first sensor and a built in test (BIT) signal, wherein the first signal path comprises a first multiplexer connected to a first filter, receiving, through a second signal path, a second secondary signal from the first sensor and the BIT signal, wherein the second signal path comprises a second multiplexer connected to a second filter, wherein the first signal path and the second signal path are connected to a third multiplexer, wherein the third multiplexer is connected to a first analog to digital converter (ADC), receiving, by a controller, an output signal from an output of the first ADC, and determining, by the controller, a position measurement for the first sensor based on the first secondary signal, the second secondary signal, and the BIT signal.

A method for the diagnosis of the offset of the resolver of an electric motor, comprising acquiring a predetermined offset of a resolver associated with the electric motor; in a first transient, supplying an excitation current to the phases of the electric motor. As a consequence of the excitation current, a current established on the axis d of minimum reluctance and a current established on an axis q in phase quadrature with respect to the axis of minimum reluctance are determined. The correctness of the offset of the resolver is diagnosed if the current established on the axis d in the first transient is higher than the current established on the axis d in the second or third transient, and if the current established on the axis q in the first transient is lower than the current established on the axis q in the second or third transient.

The rotation detection device includes: an encoder having to-be-detected patterns cyclically arranged in the circumferential direction; and a sensor configured to detect the to-be-detected patterns to generate pulses. The device further includes a reference pattern storage unit, a phase difference detection unit, and an error correction unit. The reference pattern storage unit measures pitch errors in the to-be-detected patterns prior to operation and stores the pitch errors as a reference pattern Pref. The phase difference detection unit determines a pitch error pattern Pm corresponding to one rotation of the to-be-detected patterns from rotation signals representing a plurality of rotations detected during operation, and performs comparison with a reference pattern Pref to determine a relative phase difference φ. Based on the phase difference φ obtained by the phase difference detection unit, the error correction unit corrects errors included in the rotation signals detected by the sensor.

A device is provided that comprises a hardware segment and an actuator to adjust a position of the segment within a range of positions. The device also comprises an encoder to rotate about an encoder axis responsive to the actuator adjusting the position. The device also comprises data storage that includes a dataset indicating offset angles between a reference configuration and a plurality of configurations of the encoder. The device also comprises a controller to cause the actuator to adjust the position to an end of the range of positions, responsively identify a range of encoder positions of the encoder that corresponds to the range of positions of the segment, modify the dataset such that the reference configuration corresponds to an end of the range of encoder positions, and determine a mapping between the offset angles indicated by the modified dataset and the range of positions of the hardware segment.

Method for determining a measuring offset of a rotor position sensor (2) assigned to a rotor (3) of an electric machine (5) comprising stator windings that are supplied by an inverter (6) converting a voltage at a DC link capacitor (7) into an AC current, wherein a candidate value for the measuring offset is determined, comprising the following steps: —controlling a power unit (9) of the inverter (6) to provide the current based on rotor position information (19) measured by the rotor position sensor (2) to the stator windings such that the DC link capacitor (7) of the inverter (6) is actively discharged, —evaluating a plausibility of the candidate value for the measuring offset based on a voltage of the DC link capacitor (7) detected while the power unit (9) is controlled to actively discharge the DC link capacitor (7), and —providing the candidate value as determined measuring offset, if a result of the evaluation is positive.