Delay Feedback Control And Adaptive Snyehronization Of Chaos System

Chaos is kind of complex behaviors of determinate nonlinear system. The behaviors seem be orderly, but sometimes don't. because chaos is very sensitive to initial condition, the behaviors are unpredictable. The discovery of complex phenomenon in power system and foundation, development of chaology opens up new era of nonlinear science, is called third revolution in phsics except the relativity theory and quantum theory at the 20th century.Diversity of chaotic system decides diversity of control methods, a kind of method or mode is not expected to control chaos phenomenon in nature.The paper mainly uses delay feedback and adaptive snyehronization to control chaos system to get steady working condition. These will be discussed in the third and fourth chapter in detail.Delay feedback method is a important tool to control chaos. In the third chapter, firstly chaos phenomenon of permanent-magnet synchronous motor is studied, then through making use of the bifurcation theories of delay differential equations, analytical method that chaos of permanent-magnet synchronous motor is controlled through delay feedback method is studied, and the analytic expression of between chaos condition and control parameter is got. The method is simple, effective, the emulational results indicated that theory analysis is correct.Hyperjerk system is the mode that sporrt proposed with chaos, hyperchaos and other relational behavior, and gets importance from chaos researchers. The paper studies stablity, existence of periodic solutions of a four dimension hyperjerk system, and makes use of the result to control the chaos of the four dimension hyperjerk system. At the same time correlative circuit and emulational results are given.The characteristics of chaos signal are nonperiodic, serial wide spectrum, like noise. In recent years, chaos snyehronization and it's application in secure communication have been the research hotspots. In fourth chapter, adaptive snyehronization method is used to control a four dimension hyperjerk circuit, and how to realise is discussed. But many current method is discussed based on the parameters of active system is known and the passive system can be constituted. Because in actual system, parameters are always varied and system is always been interferenced by enviroment, but a tiny behavior will bring on roomy change. So it is necessary to research chaos adaptive snyehronization to uncertain system. The chapter studies adaptive snyehronization method and the emulatinal results are given.