How to effectively ensure the service life of LED street lights?
Whether it is a customer or a manufacturer, it is hoped that the energy efficiency will ensure the service life of LED street lamps. From the customer's point of view, ensuring the service life of LED street lights can save a lot of costs, and the manufacturer's point of view is the same, ensuring the service life of LED street lights will reduce the maintenance of street lights during the warranty period, which can also save costs. At the same time, it also makes its LED street light products more competitive, and ensuring the service life is a product advantage and an advantage in the market. Below, Yaorong Technology will share with you how we effectively ensure the service life of LED street lights?
1. Design of heat dissipation and protective structure: The heat dissipation of LED street lamps is one of the key problems to be solved. It is not only directly related to the luminous efficiency of LEDs in actual work, but also because of the high brightness requirements and large heat generation of LED street lamps. Harsh, if the heat dissipation is not good, it will directly lead to rapid aging of the LED and reduced stability. Road lamps used outdoors should also have a certain level of dust and water resistance (IP),
One design uses thermally conductive plates in critical heat dissipation locations. The heat-conducting plate is inside the metal plate, evenly distributed with thin tubes for refrigerant flow, and the thin tubes are filled with refrigerant. When a certain part of the heat-conducting plate is heated, the refrigerant in the thin tubes will flow rapidly and make the heat rapidly. ground conduction. The heat dissipation of the LED will play a multiplier effect with half the effort.
The other is to design the shell of the lamp as a radiator. At present, most road lamps and lanterns shells are made of aluminum. Directly using the outside of the lamp shell as a radiator can not only ensure the requirements of IP protection level, but also obtain a large heat dissipation area. , can be washed by natural wind and rain, so as to ensure the continuous effectiveness of the radiator work.
2. Secondary light distribution optical design: Secondary optical design is an important technology that determines the light distribution curve, output light efficiency, uniformity, and glare index of LED street lamps. Through the secondary optical design, the illumination range and luminosity curve of the LED meet the needs of road lighting. Road lamps using LEDs should make use of the directional light emission characteristics of LEDs as much as possible, so that each LED in the road lamps directly emits light to each area of the illuminated road, and then uses the auxiliary light distribution of the lamp reflector to achieve A very reasonable comprehensive light distribution of road lamps.
3. Design of constant current drive circuit: The requirement of LED on the drive circuit is to ensure the characteristics of constant current output, because the relative change area of junction voltage is very small when the LED is working in the forward direction, so the constant LED drive current is basically guaranteed. Constant LED output power. For the current situation of unstable power supply voltage supply in our country, it is very necessary for the driving circuit of the road lamp LED to have a constant current output characteristic, which can ensure the constant light output and prevent the over-power operation of the LED.
In order to make the LED drive circuit exhibit constant current characteristics, the output internal impedance must be high when looking inward from the output end of the drive circuit. When working, the load current also passes through this output internal impedance. Using an active electronic switch circuit or using a high-frequency current to drive the LED can make the drive circuit maintain a good constant current output characteristic. conversion efficiency.
