Patent ID: 9091467
Filing Date: 2015-07-28
Classification: F25B,F25D,G01N

Abstract:
1. An apparatus, comprising: a thermal chamber; an external heatsink disposed externally to the thermal chamber; an internal heatsink disposed within the thermal chamber; one or more thermoelectric devices thermally coupled to the external and internal heatsinks to transfer heat therebetween in response to a pulse-width modulated power signal; a first temperature sensor disposed within the thermal chamber continuously measuring a chamber temperature; a second temperature sensor coupled to the internal heatsink within the thermal chamber continuously measuring temperature at the internal heatsink; and a feedback control system including a first controller in communication with the second temperature sensor as part of a first feedback control loop, the controller calculating the duty cycle of the pulse-width modulated power signal at which to operate the one or more thermoelectric devices in response to a target internal heatsink temperature and a real-time internal heatsink temperature measured by the second temperature sensor, wherein the feedback control system includes a second controller in communication with the first controller and the first temperature sensor as part of a second feedback loop, the second controller calculating the target internal heatsink temperature in response to a target chamber temperature and a real-time chamber temperature measured by the first temperature sensor, wherein the second controller passes the calculated target internal heatsink temperature to the first controller, and the first controller supplies the pulse-width modulated power signal to the one or more thermoelectric devices.