A new angle determination method for resolvers

Abstract

A new low cost method for converting the amplitudes of the sine/cosine signals generated by the resolver into a measure of the angle of its shaft. The new method operates without lookup tables (LUT), and takes advantage of the components used to operate the resolver, the excitation (carrier) signal in particular. The method is based on a feed-forward technique that uses amplitude comparison technique in order to determine the angle from the excitation of the resolver. An appropriate technique is proposed to avoid unreliable comparison that may result by using the highly non-linear peaks of the sine and cosine signals. This results in a better accuracy in the estimation method. Beside simplicity of implementation, the proposed scheme offers the advantage of robustness to amplitude fluctuation of the transducer excitation signal. © 2008 IEEE.