The influence of operating temperature conditions of led modules on their electro-optical and operational parameters

Modern LEDs are characterised by high energy efficiency, which makes them one of the most promising light sources in many industries. The efficiency and durability of LED modules largely depend on the temperature conditions of operation. Elevated temperatures can adversely affect electro-optical parameters such as luminous flux and spectral characteristics, as well as accelerate degradation processes. This article investigates the effect of temperature conditions of LED modules on their electro-optical and operational parameters. The paper considers how temperature unevenness in the LED module affects their luminous flux and service life. It is determined that when assessing the efficiency and durability of LED modules, it is necessary to take into account the standard deviation of the LED temperature from the average. Given the presence of temperature gradient between LEDs in a LED module, the service life of the latter is estimated by the temperature of the most heated LED, as shown in this paper. The influence of the deviation of the LED temperature from the average on the overall luminous efficiency of LED modules based on them is demonstrated. In particular, with a standard temperature deviation of 20°C, the relative decrease in the module’s luminous flux can be about 1%. For the considered cases, an increase in temperature unevenness by 10°C reduces the lifetime of the LEDs more than three times. To ensure the efficient operation of LED modules, it is necessary to reduce the standard deviation of temperature from the mean value through effective heat dissipation and improved cooling system design. The use of LEDs with lower temperature coefficients can also reduce the sensitivity to temperature fluctuations, increasing the overall luminous flux and luminous efficiency of LED lighting devices based on them.