LED chip and power supply are installed together
2019-08-26 18:44:19
LED chip and power supply are installed together, the general space is small, and the heat dissipation condition is poor. We believe that the performance that affects the life of LED power supply includes environmental characteristics, components and character of the electric power, and the following aspects are integrated:
1.Impact of actual application environment: high humidity environment, high temperature environment, dusty environment, strong magnetic environment, vibration environment
2.the effect of lighting temperature environment: the internal temperature of the lighting is less than 65 degrees, the lighting enclosure is less than 75 degrees, the power supply temperature is less than 60 degrees
3. Impact of the power supply grid: The voltage input of the unstable power grid will impact the components of the LED power supply, thus affecting the service life of the LED driver.
4. the impact of insulation and installation: the correct installation of the product and good insulation will enhance the application of LED power.
5. the impact of electrolytic capacitors: the sealing part of the electrolytic capacitor will leak out of the vaporized electrolyte, this phenomenon will accelerate with the increase of temperature, it is generally believed that for every 10 °C rise in temperature, the leakage speed will increase to 2 times. For every 10 °C rise in electrolytic capacitor temperature, the life will be halved.
Therefore, it can be said that the electrolytic capacitor determines the life of the power supply unit.
The normal working life of an LED driver depends on the life of the electrolytic capacitor used by the power supply. The life of the electrolytic capacitor depends on the life of the capacitor itself and the operating temperature.
6. Influence of switching times: Most power supplies have a capacitor input type rectification circuit. When the power is turned on, a surge current will be generated, resulting in fatigue of the switch contacts, causing problems such as increased contact resistance and adsorption. In theory, it is believed that the number of switching times of the switch is about 10,000 times during the expected life of the power supply.
7. Impact of inrush current protection resistor and thermal power resistor: In order to offset the inrush current generated when the power is supplied, the design of the power supply is usually used in parallel with the SCR and other components.
When the power is turned on, the peak value of the power is as high as several tens to hundreds of times the rated value, resulting in thermal fatigue of the resistor, causing an open circuit. Thermal fatigue resistors in the same situation can also cause thermal fatigue.
