Patent ID: 6255794
Filing Date: 2001-07-03
Classification: G01P,H03M

Abstract:
Method for the digital evaluation of the analogue output signals of a resolver with at least two stator windings arranged in a perpendicular position to each other on a stator, and at least one rotor winding arranged on a rotor which can turn in relation to the stator, comprising the following steps:A) applying a sinusoidal excitation signal to the rotor winding;B) deriving sinusoidal and cosine-shaped signals, respectively, depending on the angular position of the stator in relation to the rotor, from the stator windings and, after oversampling, are converted into digital signals;C) passing the digital signals through an FIR bandpass filter for bandwidth limiting;D) subjecting the filtered signals to decimation using the factor applied to the previous oversampling process;E) computing the inverse tangential function to derive an angular value for the relative angular position between the rotor and the stator, affected by a propagation delay error due to the preceding process, from the signals subjected to the decimation process;F) applying the computed angular value to the input of a control loop, in whicha) the computed angular value is compared with an assumed delay-time affected angular value,b) the deviation between the computed angular value and the assumed angular value is applied to a PI regulator as regulation deviation value,c) from the applied regulation deviation, the PI regulator generates an output signal corresponding to the angular velocity of the rotor without propagation delay,d) the output signal is subjected to IIR filtering,e) the assumed angular value, not affected by delay time, is obtained from the filtered output signal by integration,f) the assumed angular value is delayed by the propagation time value and fed to the unit which compares it with the computed angular value, andG) the assumed angular value and the angular velocity without propagation time delay become available as the output signals of the resolver.