Patent ID: 7904267
Filing Date: 2011-03-08
Classification: G01D

Abstract:
1. A method for identifying and compensating for position errors in resolver output signals, comprising the steps of: a) receiving a first resolver output signal; b) receiving a second resolver output signal; c) approximating the first resolver output signal as a first equation wherein the first equation is a first Fourier series based on a cosine function of an angular position θ; d) approximating the second resolver output signal as a second equation; e) using the assumed orthogonality of said first resolver output signal and said second resolver output signal to create a third equation which defines a first error factor as a function of a first constant minus the squares of said first equation and said second equation, wherein said first constant is 1; f) cross-correlating the third equation with cos(θ), sin(θ), cos(2θ), sin(2θ), and the first constant to determine a plurality of compensation signals; g) using the plurality of compensation signals in a feedback loop to create a corrected first resolver signal and a corrected second resolver signal; h) using the corrected first resolver signal and the corrected second resolver signal to determine, by a processor, a corrected angular position θ of the resolver; and i) outputting a corrected output signal representing the corrected angular position θ to a position controller.