Approximate Frequency-Response Methods for Representing Saturation and Dead Band

This paper indicates there are numerous nonlinear elements having saturation or dead-band characteristics for which an “equivalent linear coefficient” may be used as the describing function. The equivalent gain factors for saturation and dead band are shown to have a somewhat complementary nature and to be of relatively simple form. Although the results of using this approximate method of analyzing backlash and saturation do not provide an exact solution, they do permit the designer to obtain useful qualitative results. As such, this method is particularly helpful for use in the more complex systems such as are generally encountered in practice, but that do not lend themselves to more exact analytical treatment.