TEG&Li+ batteries to power data collection sensors

[omar-us]

Hi all,

This is Omar undergraduate electrical engineering student. I am doing my senior project on powering data collection sensors( 3- resistance temperature detectors and 1- pressure transducers) of autoclave by using thermoelectric generator!. the sensors are connected in // to a 24V common node and use a roughly 2A when the sensors are transmitting data to the receiver"its peak value!". As the autoclave uses steam, I was asked to build a complete power system that can supply the sensors as its without redesigning being involved by using the TEG's!. After days of thinking and reading across the internet, I realized there is no such a way to power the high power consuming sensors I am dealing with by TEG's alone!. I came up with an Idea and I would like to get your inputs and advice to achieve it if its valid!.

The idea is based on the cell-phone charging! I mean we can use the cell-phone while we are charging its battery and I figured why not to use a rechargeable battery that can supply enough energy and use boost converter to get to 24V while there will be a trickle charge circuit that can store the TEG's output power "SC" and supply the battery with charge when its efficiency below 85%.! Also, the hole system has to be self controlled " ex: when the autoclave is not operating the battery has to stop supplying the sensors! I am thinking about using MOSFT transistor as a switch that is base is dependent on the TEG's output in order to kill the power line!. On the other hand, I am totally lost where should I start in order to build the system! I have read a lot regarding on rechargeable battery types how to trickle charge it but no Idea how to build voltage controlled current source by using TEG's and determine the correct value of SC to store the energy and how to trickle charge the circuit when the efficiency 85%!Plus, how I can trickle charge the battery while its supplying the sensors and is it possible! and the big question is how to isolate the stages! is didoes enough to prevent current change direction! " there will be voltage drops and I am trying to save as much power as I can"!.

any thoughts will be highly appreciated. BTW English is not my first language so excuse me if you don't understand what I am saying will be happy to explain again ^_^''

Regards

 

[Rive]

Hi,

... sensors are connected in // to a 24V common node and use a roughly 2A

Just what kind of (transmitting data -> digital?) sensors would consume 50W total in operation? Are you sure about those numbers?

2A is just extreme. To power it with TEG would require so much effort, that - by my opinion - to replace those sensors with some decent ones (which are not some leftovers from the cold war era, judged by the consumption) would result in a far cheaper project.