Study Of Nonlinear Behavior And Chaotic Control In Two Typical DC/DC Converters

DC/DC converter is the core part of switch power supply is composed of nonlinear components such as diodes,switching tube,belonging to the strongly nonlinear system,which contains the rich nonlinear characteristics.When the sensitive parameters of system changing,the system can produce all kinds of bifurcation behavior,finally into the chaotic state.System to produce these nonlinear phenomena,will seriously affect the normal work of the whole system,some serious instability,eventually lead to the collapse of the system,so it is particularly important to avoid the occurrence of this phenomenon.And with continuous improvement and perfection of power electronic technology,the power electronic systems and devices on the reliability and the performance index requirements more and more highly,so in practice,of the converter is necessary to avoid chaos area,also is inevitable.So the study of chaos and its control method in the converter will help us to avoid or eliminate this kind of phenomenon in the design,make the converter working in stable period,for the correct design and debug switch power has important guiding significance.In this paper,in order to Boost and master-slave parallel Buck converter control as the research object,study the bifurcation and chaos behavior mechanism and the control method of chaos,pushed the system stability conditions and main parameters in detail the stability of the scope of work,for the design of the converter parameters,to improve the performance of the whole system has very important guiding significance.Finally,in view of the phenomenon of chaos,chaos control strategy would be in a chaotic state of converter control to a stable periodic state.In this paper,the main work is as follows:(1)The advantages and disadvantages of commonly used modeling methods are analyzed,finally chose the more widely used,is the most suitable method of discrete modeling.To Boost and master-slave control Buck converter in parallel as an example,the discrete iteration model is established.(2)The reference current and output resistance as bifurcation parameter,the Boost converter is analyzed as the change of system parameters,the bifurcation behavior occurred until the state of chaotic behavior.Master-slave control method was applied,thevoltage feedback Buck converter in parallel implementation of all flow control,analyzes its under the flow characteristics of bifurcation and chaos phenomena.(3)Using numerical method to Boost and master-slave control Buck converter in parallel to the stability analysis,with reference to current parameters is deduced the steady working range of the Boost converter.(4)Using method of oblique wave compensation and parameter resonance disturbance control of Boost and master-slave parallel chaos control in the Buck converter,using MATLAB software to the simulation,to verify the effectiveness of the two kinds of chaos control strategy.