Patent ID: 7904267

Claim:
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; wherein the second equation is a second Fourier series based on a sine function of a first sum which represents the angular position θ plus a phase error φ; and wherein the second resolver output signal is assumed to be ninety degrees out of phase with the first resolver output signal; 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.