Dynamic switching thermoelectric thermal management systems and methods

Abstract

A dynamic switching thermoelectric thermal management system and method is disclosed. The thermal management system includes a heat dissipation device, a thermoelectric module, an ambient temperature sensor, a heat source temperature sensor, an energy storage device and a controller. One side of the thermoelectric module is thermally coupled to the heat source and another side is thermally coupled to the heat dissipation device. The controller periodically samples the temperature sensors and dynamically switches the thermoelectric module between a power generation mode in which the thermoelectric module uses the temperature difference between the heat source and ambient to charge the energy storage device, a cooling mode in which the thermoelectric module is powered to create a voltage difference across the thermoelectric module to cool the heat source, and an idle mode. The thermal management system can be integrated into a portable electronic device, for example a portable computing device.

1 . A dynamic switching thermoelectric thermal management system for coupling to a heat source, the thermal management system comprising:
 a heat dissipation device;   a thermoelectric module having a first side and a second side, the first side being thermally coupled to the heat source and the second side being thermally coupled to the heat dissipation device;   a first temperature sensor detecting the ambient temperature of the environment surrounding the thermal management system;   a second temperature sensor detecting a temperature for the heat source;   an energy storage device; and   a controller coupled to the thermoelectric module, the first and second temperature sensors and the energy storage device;   wherein the controller periodically samples the first and second temperature sensors and dynamically switches the thermoelectric module between a power generation mode in which the thermoelectric module uses the temperature difference between the heat source and ambient to charge the energy storage device, a cooling mode in which the thermoelectric module is powered to cool the heat source, and an idle mode in which the thermoelectric module neither generates or consumes power.   
     
     
         2 . The thermal management system of  claim 1 , further comprising a heat spreader having a proximal end and a distal end, the proximal end of the heat spreader being coupled to the heat dissipation device and the distal end of the heat spreader being coupled to the heat source, the first side of the thermoelectric module being coupled to the heat spreader. 
     
     
         3 . The thermal management system of  claim 2 , wherein the controller is a programmable microchip. 
     
     
         4 . The thermal management system of  claim 2 , wherein the second temperature sensor is coupled to the distal end of the heat spreader. 
     
     
         5 . The thermal management system of  claim 4 , wherein the first temperature sensor is coupled to the heat dissipation device. 
     
     
         6 . The thermal management system of  claim 1 , wherein the heat dissipation device is a heat sink having a plurality of fins. 
     
     
         7 . The thermal management system of  claim 1 , wherein the heat dissipation device is a liquid cooling device. 
     
     
         8 . The thermal management system of  claim 1 , wherein the heat dissipation device dissipates heat to the surrounding environment by conduction. 
     
     
         9 . The thermal management system of  claim 1 , further comprising a fan forcing fluid over the heat dissipation device to dissipate heat to the surrounding environment by forced convection. 
     
     
         10 . The thermal management system of  claim 1 , further comprising a pump forcing liquid over the heat dissipation device to dissipate heat to the surrounding environment by forced convection. 
     
     
         11 . The thermal management system of  claim 1 , wherein the energy storage device is a battery. 
     
     
         12 . The thermal management system of  claim 1 , wherein the energy storage device powers the thermoelectric module during cooling mode. 
     
     
         13 . The thermal management system of  claim 1 , further comprising a portable electronic device into which the thermal management system is integrated. 
     
     
         14 . The thermal management system of  claim 13 , wherein the portable electronic device is a portable computing device. 
     
     
         15 . A method for controlling a dynamic switching thermoelectric thermal management system that includes a thermoelectric module having a first side thermally coupled to a heat source and a second side thermally coupled to a heat dissipation device, the method comprising:
 monitoring a heat source temperature of the heat source;   monitoring an ambient temperature of the ambient environment surrounding the thermal management system;   dissipating heat from the heat source using the heat dissipation device;   when the heat source temperature is greater than the ambient temperature and less than a critical working temperature, putting the thermal management system in a power generation mode for charging an energy storage device using the temperature difference across the thermoelectric module; and   when the heat source temperature is greater than the critical working temperature, putting the thermal management system in a cooling mode for cooling the heat source using a voltage difference across the thermoelectric module.   
     
     
         16 . The method of  claim 15 , wherein the energy storage device is used to create the voltage difference across the thermoelectric module when the thermal management system is in the cooling mode. 
     
     
         17 . The method of  claim 16 , further comprising conducting heat from the heat source to the thermoelectric module through a heat spreader that includes a proximal end coupled to the first side of the thermoelectric module and a distal end coupled to the heat source. 
     
     
         18 . The method of  claim 17 , wherein the temperature sensor for monitoring the heat source temperature is coupled to the distal end of the heat spreader. 
     
     
         19 . The method of  claim 18 , wherein the temperature sensor for monitoring the ambient temperature monitors the temperature near the heat dissipation device. 
     
     
         20 . The method of  claim 19 , wherein the heat source temperature and the ambient temperature are monitored periodically.