Design And Research Of High Performance LED Power Supply System

Light emitting diodes(LED)have many advantages,such as long life,high efficiency,rich color,no environmental pollution,good optical properties and so on,it is a new generation of semiconductor solid lighting source.With the LED driving power supply technology is gradually mature,it has been widely applied in social life and industrial production in various fields,and has become the first choice of modern lighting,and is recognized as the most valuable source of green lighting.High performance power supply is a key part of LED lighting system,which quality has a direct impact on the length of life and overall performance.We know that the general electrolytic capacitor only a few thousand hours of life,and the life of electrolytic capacitors has a great relationship with LED drive power supply.This thesis is aiming at the problem that electrolytic capacitor does not match the LED drive power supply,we can by removing or using other relatively long service life of the capacitor to replace electrolytic capacitor to solve the problem of short service life of the LED driver power.The innovation and main work of this thesis is as follows.(1)Aiming at the problem of short service life of driving power,existing technology uses three harmonic current injection method to reduce the capacitance value,so as to use thin film capacitors instead of electrolytic capacitor,but three harmonic injection will bring problems to the strobe circuit.Therefore,this paper uses three harmonic current injection and current feedforward control strategy innovative to remove the electrolytic capacitor in the circuit,and the output ripple current on the load is very small,will not bring the stroboscopic phenomenon to the load..(2)This thesis used the saber software to verify the design of the program circuit,when using the 10 uF film capacitor instead of the current capacitor in the circuit,its ripple current is 1.81% of the output current,it will not cause the strobe problem of the load.(3)Based on the above mentioned scheme,the main parameters such as transformer,rectifier bridge and switch tube are designed and explained in detail;in the Altium Designer software,the whole system circuit and PCB circuit have been designed,and the circuit board has been fabricated and welded.Experiments show that can use three harmonic current injection and current feedforward control to remove the electrolytic capacitor of the whole power system,and not to the load caused flicker,thereby improving the service life of power and stability.