Interleaved Delay Control And Stability Analysis Of CCM SIDO Buck Converter

Single-inductor Multiple-output(SIMO)converter needs only one energy storage inductor to realize independent output of multiple branches,which reduces the number of control chips and energy storage inductors.Thus reduces the cost and size of power supply.It provides an ideal design scheme for computers,mobile phones and other electronic devices that need two or more output power supply.With these advantages,SIMO DC / DC switching converter has gradually attracted the attention of scholars at home and abroad.In this thesis,the Single-inductor Dual-output(SIDO)Buck converter in the continuous conduction mode(CCM)was studied.First of all,the topology,operating principle and four common working modes of SIDO Buck were presented,the time-average equivalent circuit of converter was built,DC equivalent circuit AC equivalent circuit were constructed.the output voltage DC gain expression and AC power level function of the two branches were derived.And the small signal model is established.The results show that the timing can be confirmed by regulating the output current,and the on duty cycle of the switch in the circuit will affect the voltage gain of CCM SIDO buck converter.In addition,the load change on one branch will affect not only the voltage gain of the branch,but also the voltage gain of the other branch.Secondly,the voltage mode control CCM SIDO Buck converter was consided as object,and two different working paths were introduced in detail due to the different turn-on sequence of the switch duty cycle.Two discrete iterative model was established and the Jacobian matrix at the fixed point was derived.The effect of the parameters in the circuit on the stability was further considered.With the decrease of the proportional gain of the branch switch control and the magnify of the proportional gain of the master switch control and the input voltage,the system go into low frequency oscillation.and based on the established discrete iterative mapping model and the derived Jacobian matrix,the eigenvalue motion trajectory was obtained,which theoretically verifies the stability and bifurcation with the parameters varying,and the simulation circuit analysis further verifies the correctness of the conclusion.Finally,based on the voltage mode control of the CCM SIDO Buck converter,a new interleaved delay control scheme is proposed.By introducing a more general delay parameters,the two-phase interleaved is extended to more flexible delay interleaved,and the effect of the interleaved delay on stability was investigated,the effects of different parameter settings on the stability interval and the corresponding optimally interleaved delay are analyzed.and the four working paths and mode switching of CCM SIDO Buck converter under interleaved delay control are analyzed in detail,four iterative mapping models and Jacobian matrix at fixed point of CCM SIDO Buck converter are derived.The results show that: in a certain range,the introduction of interleaved delay can improve the stability of the system,and the change of circuit parameters will have a certain impact on the stability range.With the increase of inductance,the stability range of the system will increase.However,with the increase of load and capacitance,the stability range of the system will gradually decrease.The introduction of optimally interleaved delay can greatly improve the stability of the system,and the stability interval of the system increases significantly.The research method and results have important reference significance for stability design and bifurcation control of SIDO Buck converter.