Research of the Test Algorithms of Servo System Frequency Characteristics

Servo system sweep signals are subject to severe interferences including noise, resonance, and drift. Therefore, it is necessary to study the applicability of various calculation methods of frequency characteristics. In this paper, the principles and characteristics of fast Fourier transform, correlation analysis, and power spectrum estimation are summarized, the improved least squares fitting is proposed to enhance the processing for complex drift interference, and the equivalent properties of correlation analysis and the traditional least squares fitting were found.