Electrothermal Collaborative Cooling With Delayed Power Rail Switching Auxiliary Charging by Considering Energy Harvesting Mechanism for High-Power LEDs

With the development of high-power light-emitting diodes (LEDs), the heat flux density of devices has continued to increase, which, in turn, requires the development of increasingly effective methods of heat dissipation to control the working temperature of LEDs. Due to their impressive performance in solid refrigeration and energy harvesting, thermoelectric devices such as thermoelectric coolers (TECs) and thermoelectric generators (TEGs) have been used to develop the methods of heat dissipation, which have been applied to power components and electronic devices. This article proposes a delayed electrothermal collaborative cooling system based on a TEC-TEG system that uses an auxiliary charging technique for energy harvesting. In the designed delay circuit, two power source rails containing a TEG and a charged capacitor are switched automatically to supply energy to a TEC according to the charge on the capacitor and the discharge time of the delay circuit used for energy transmission. The results of experiments show that using the proposed scheme, the electromotive force can be increased by 21.6%, from 0.37 to 0.45 V, in the TEG module compared with the collaborative electrothermal cooling system without auto-delayed power rail switching. The switching time cost of the proposed system was only 0.8 s, and it could continuously supply enough electromotive force to drive the TEC and the overall cooling system. The proposed electrothermal collaborative cooling system with delayed power rail switching and auxiliary charging can improve energy utilization and reduce device cost, which helps to efficiently manage heat dissipation in high-power LEDs.