Research On Interleaved-control Double-input Buck Converter

The double-input Buck converter allows access to two power supplies with different amplitudes.Compared with single-input Buck converter,double-input Buck converter has the characteristics of less number of devices,small size and low production cost.It has broad application prospects in the clean energy market and has become a research hotspot of scholars at home and abroad in recent years.Taking the interleaved control double-input Buck converter as the research object,the input voltage is divided into three cases,and the working mode of the converter is analyzed in deep.It is pointed out that when the converter works in different input voltage ranges,there is a continuous conduction mode（CCM）and two discontinuous conduction modes（DCM）.According to the switching conditions of the converter operating modes in different input voltage ranges,the analytical formula of the critical inductance is obtained.The mathematical models of inductor ripple current and output ripple voltage in different working modes are established.The characteristics of inductor ripple current and output ripple voltage models are summarized.It lays a theoretical foundation for the circuit parameter design of the converter.In order to obtain the control parameter range of interleaved control double-input Buck converter,the mathematical model of the double-input Buck converter is established by applying the state space averaging method.The Jacobian matrix of the system is derived,and the stability of the system which combined with Rouse Herwitz criterion is analyzed.The stable range of the control parameters of the closed-loop system is obtained.The discrete mapping model of the system is established.The typical working state of the system corresponding to different parameters is studied by using phase trajectory diagram,which lays a theoretical foundation for the design of the controller parameter.In order to present more comprehensively characterize the influence of controller parameters and circuit parameters on system stability,the eigenvalue sensitivity theory is used to analyze the influence degree of each parameter on system stability.The influence trend of each parameter on system stability is obtained.It lays a theoretical foundation for the optimal design of the converter parameters.In order to design an interleaved control double-input Buck converter which meets the electrical performance index of requirements,the parameter design method is obtained.The variation trends of critical inductance,inductance ripple current and output ripple voltage with inductance,capacitance and input voltage are discussed.Taking the working mode,inductance ripple current and output ripple voltage as constraints,the value range of inductance and capacitance in the dynamic variation range of input voltage and load resistance are obtained.According to the stability condition and eigenvalue sensitivity theory,the parameter range of the controller is obtained.Finally,an experimental platform is built,and the experimental results show the rationality of the parameter design method.