报告题目：Analysis of chattering and propagation of external inputs for dynamically perturbed systems with homogeneous FT controllers
The Homogeneous Finite- Time Controllers (HFTC) is proposed to reduce the magnitude of the oscillations caused by the presence of fast-parasitic dynamics in relative degree one systems. The Describing Function (DF) approach is used to predict the amplitude and frequency of fast oscillations. A set of the HFTC gains is suggested to minimize the amplitude of chattering. The analysis of propagation of perturbations is done using the Equivalent Gain (EG) approach showing that due to the integral controller, it is possible to fully compensate constant perturbations. In addition, propagation of harmonic perturbations is computed through standard Transfer Function techniques with the usage of the computed EG. Simulations and DF-EG predictions allow to conclude that it is possible to improve the sliding accuracy of the output selecting the parameters of the HFTC reasonable. The latter is pending on the velocity of fast parasitic dynamics.
Leonid M. Fridman received an M.S. degree in mathematics from Kuibyshev (Samara) State University, Samara, Russia, in 1976, a Ph.D. degree in applied mathematics from the Institute of Control Science, Moscow, Russia, in 1988, and a Dr. Sc. degree in control science from Moscow State University of Mathematics and Electronics, Moscow, Russia, in 1998. From 1976 to 1999, he was with the Department of Mathematics, Samara State Architecture and Civil Engineering University. From 2000 to 2002, he was with the Department of Postgraduate Study and Investigations at the Chihuahua Institute of Technology, Chihuahua, Mexico. In 2002, he joined the Department of Control Engineering and Robotics, Division of Electrical Engineering of Engineering Faculty at National Autonomous University of Mexico (UNAM), Mexico. His research interests are Variable Structure Systems. In 2014-18 Professor Fridman served as a Chair of TC on Variable Structure and Sliding Mode Control. He is a winner of Scopus prize for the best cited Mexican Scientists in Mathematics and Engineering 2010 and 2019 UNAM Prize for research in exact sciences. Actually, he is International Chair of INRIA and High Level Research Expert in Secretary of Education of China. He was working as an invited professor in 20 universities and research laboratories of Argentina, Australia, Austria, China, France, Germany, Italy, Israel, and Spain.