Position sensors are used for motor drive controls.
Usage of magnetic encoder is appropriate for sensing position in robust industrial environment.
Magnetic encoder senses the angular position of a permanent magnet placed above the sensor.
The permanent magnet must be diametrically polarized and of cylindrical shape.
Encoder uses Hall sensors to detect magnetic flux density.
Signals from Hall sensors are then converted to signals in shape of sine and cosine. From sine an cosine signal, an angle calculation algorithm is performed.
Algorithm could be presented by mathematical function of atan2().
Incorrect installation of sensor or magnet, causes error in output angle.
This work presents, how incorrect installation of sensor or magnet impact to measured magnetic field by Hall sensor.
Incorrect installation can be recognized from field measured by Hall sensors. Encoders output signal is only angle.
In this thesis is demonstrated how to recognize changes of signals from Hall sensors, by knowing encoder output only.
The basic simulation model was built in MATLAB. Simulations were made by linear approximation of Z-component of magnetic field and numerical calculations by magnet model.
Encoders error was analyzed in frequency spectrum.
Simulations have been compared to the encoder RM44 measurements.
Simulation results of error has been confirmed by measurements. Best installation of sensor was determined empirically.
Empirical determination of installation, has been resulting in the output error.