Topologies And Control Methods Of Add-in Energy-Recycle Circuits

Base on the original current-sharing interface circuits and an energy-recycle strategy,add-in energy-recycle circuits can successfully deal with the cases of large voltage differences between input and output with high efficiency.In different applications,add-in energy-recycle circuits have different topologies and meet the application requirements with the help of control methods.Meanwhile,the add-in energy-recycle circuits have the characteristics of high extensibility,flexible,convenient,etc.At first,this thesis introduces add-in energy-recycle circuits which are applied to power modules current-sharing,LED matrix driving and photovoltaic array.This thesis focuses on two kinds of topologies and control methods which is applied to LED matrix driving and photovoltaic array respectively.Secondly,this thesis study an energy-recycle interface circuit for LED matrix driving and control methods.The operation principle of this circuit is introduced and the main equations and inequations are given.In order to achieve high efficiencies all over the load range,a maximum-efficiency operation point locating control method is proposed,which can make an energy-recycle interface circuit for LED matrix driving automatically find a nearly maximum-efficiency state and finally operate at that steady state.For experimental verification,a single-channel prototype was implemented.The experimental results show that a single-channel prototype of the energy-recycle interface circuit for LED matrix driving under the proposed control method could achieve both nearly maximum efficiencies in the normal-load cases and nearly minimum losses in the fault-load cases with high probabilities.The results also show that most of the experimental data agreed with the theoretical ones within the whole load range and the experimental steady-state waveforms agreed with the ideal steady-state waveforms.Base on the maximum-efficiency operation point locating control method,this thesis proposes a maximum-efficiency operation point tracking control method,which can make an energy-recycle interface circuit for LED matrix driving track the maximum-efficiency operation point when the load changed.For experimental verification,a three-channel prototype was implemented.The experimental results show that the three-channel prototype of the energy-recycle interface circuit for LED matrix driving was able to drive the abnormal LED matrix with high efficiency.And under the proposed control method,the three-channel prototype could achieve nearly maximum efficiencies in the fixed-load cases and again achieve nearly maximum efficiencies after the load changed with high probabilities.Finally,this thesis study an energy-recycle interface circuit for maximum power point tracking control and control method.The operation principle of this circuit is introduced.Design and build a single-channel simulation circuit of the energy-recycle interface circuit for maximum power point tracking control in Matlab/Simulink.The simulation results show that the single-channel simulation circuit could locate the maximum power point quickly and accurately,and the single-channel simulation circuit could again locate the maximum power point in time when the environmental conditions changed.The simulation steady-state waveforms agreed with the ideal steady-state waveforms.