Research On High-power LED Driver Topology And Control Strategy

With the wide application of LED lamps in lighting market,the driving power supply with high design efficiency,high reliability and low cost is of great significance.At present,the mainstream LED driving power supply is PFC DC-DC two-stage with high power factor,but it has lower overall efficiency and higher production cost.This paper starts with the circuit structure and control method of high power LED drive power supply designing a single stage bridge-less driving power supply,which solves the problems of high cost and unsatisfactory control of traditional two-stage power supply.First of all,a single-stage LED drive power supply is designed in this paper,which combines the bridgeless PFC with the half-bridge LCL resonant converter in the circuit structure to realize the sharing of the switch tube,the switch components are reduced to two,and the production cost is reduced.The output capacity of the current is improved by serializing the compensation capacitor on the resonant converter.Establishing the equivalent model of the converter by using AC analysis method,the parameters of capacitance and inductance are optimized and the voltage stress is reduced.The converter has the function of soft switching,reduces the switching loss and improves the conversion efficiency.Secondly,the LED lighting system has the characteristics of variable load and uncertain parameters,the control effect of the classical PID control system is poor so that on the basis of classical PID,combined with B-spline prediction rule and artificial neural network algorithm,a neural network predictive PID control method with predictive current capability is designed in this paper.Using this method can realize anticipatory control when the load changes,it can stabilize the current output better and improve the anti-perturbation performance of the power supply.Finally,MATLAB/SIMULINK is used to modeling and simulation analysis of LED driver Power supply designed in this paper.The results show that,the power supply has the advantages of high conversion efficiency,high reliability and low switching loss in the circuit structure and neural network prediction of PID has obvious advantages over classical PID in dynamic response speed,current output stability and anti-disturbance performance in the control method.