The Study of PDF Control Technology for a Levitated Globe with Hybrid-excited Magnets

摘要

In order to realize the levitation control of the globe with the hybrid-excited magnets, the authors study the working principle and the mathematical model of the system by the methods of the mechanics analysis and theoretical calculation and obtain parameters based on experiments. According to the data the author deduce the transfer functions of the controlled globe and system. The authors utilize a PDF (Pseudo-Derivative-Feedback) control arithmetic to design the PDF controller. The authors also analyses the systemic stability, robustness and the control precision. The study shows the PDF control method is predominant in the engineering application to the nonlinear and instable system. The method posses the characteristics of robustness and high control precision.