| The switching DC-DC converters have different nonlinear dynamic behaviors under different loads,but few scholars consider DC-DC converters under memristive loads.The memristive load presents a new challenge to the study of dynamic behavior and suppression of the chaos of DCDC converter.In this paper,the switched-inductor Buck-Boost converter is taken as the object of study to research its nonlinear behavior and suppression of the chaos under the memristive load.The detailed contents of the research are as follows:Firstly,the state equation model of the single-stage switched-inductor Buck-Boost converter with the memristive load in continuous current mode is established.The MATLAB numerical simulation based on the equation of state draw the images of the inductor current such as the bifurcation diagrams,the waveforms,the phase portraits,the diagrams of poincare section and the diagrams of Lyapunov index when the peak current changes.Detailed analysing the dynamic behavior of the system with the change of peak current.And analysing the influence of circuit parameters on the nonlinear behavior when different bifurcation parameters are briefly compared.Finally,the jacobian matrix is calculated to analyze the equilibrium stability of the system.In order to verify the correctness of the results,the simulation circuit is built in PSIM to simulate.Secondly,based on the model of the single-stage switched-inductor Buck-Boost converter with the memristive load,the nonlinear behavior of the system under coupling switching inductors(codirectional coupling,reverse coupling)and series or parallel is studied.In the case of coupled inductor,the coupling degree of 0.2,0.5,0.8 is taken as examples.In the case of series or parallel,two,three and four stages are respectively taken as examples.And the bifurcation diagrams are obtained by MATLAB.The nonlinear behavior of the system with the change of coupling degree and the number of series or parallel is discussed.At the same time,the equilibrium point of the complex system is calculated and the stability of the system is analyzed.And corresponding circuit simulation is carried out by PSIM.Thirdly,based on the principle of the control by peak current,the resonant parametric perturbation method and the ramp compensation method are used to suppress the nonlinear behavior of the switched-inductor Buck-Boost converter under the memristive load.According to the numerical simulation,the appropriate values of the control parameters of the two methods are obtained,and the chaotic behavior of the system is successfully suppressed.Meanwhile,the suppressing ability of the two methods on chaotic behavior of the system under different control parameters and bifurcation parameters is discussed.Finally,the effectiveness of two methods is verified by PSIM simulation. |
