mosfet transistor full wave rectifier for energy harvesting applictions

[juni1122]

hi
i have been assigned to design this topic for my thesis i cannot understand where to start from.
if someone has any knowledge please share.it is an application of nanoelectronics

 

[tgootee]

Presumably, you will have some source of a small AC voltage, from which to harvest energy. It could be radio waves from the air, or the output of a vibration transducer, or something else.

You will need to rectify it, so that it is all of one polarity, in order to be able to charge a battery, or power some other device, or send the current somewhere.

The reason to use an active rectifier circuit, instead of a diode, is that your AC input signal's amplitude will be very small, relative to the forward voltage of any diode. An active rectifier circuit can rectify all the way down to about zero volts. So it can be used for even tiny AC amplitudes.

 

[juni1122]

i am going to use RF waves
where shall i start from?

 

[betwixt]

Start by analysing the source of energy and quantifying the amount available and the amount you need to produce.

Hint: there is VERY, VERY LITTLE energy available in most circumstances and if you want to make use of it, the energy has to be enough to not only supply your load but the circuits used to harvest it. There is no point in using active rectifiers unless you have harvested enough power to make them operate.

Brian.

 

[tgootee]

OK. There are some physical circumstances where it would make a lot of sense to harvest RF energy. Off the top of my head, the best one might be near powerful RF broadcast antennas, basically as part of the broadcast facility. They might want to harvest the RF from areas that are not in the desired antenna pattern. e.g. An FM station or a cellular phone tower would typically only want to send RF toward receiving antenna locations, i.e. mostly horizontally or slightly downward. Everything that goes at too steep of an angle either upward or downward would normally be wasted.

Another area that MIGHT be worth looking into would be in cell phones, themselves. Perhaps you could harvest the energy that goes toward the keypad side, i.e. the RF that would have been going toward the user's head, and put the energy back into a battery, or a capacitor, or help power the phone at the time.

I don't know enough about the topic to be of a lot of help. Sorry. The article at https://www.digikey.com/us/en/techz...s/tune-in-charge-up-rf-energy-harvesting.html has a few ideas, and there are links to app notes and papers on that page. A google search for RF Energy harvesting shows lots of promising-looking links.

if you are doing a thesis, normally one of the first places to start is with a literature search, so you know everything that has been done, to date, and also so you don't duplicate someone else's efforts. So, search all of the technical journals and read all of the papers that are out there. Then you will know exactly where to start, so that your work will be something new that is advancing the current state of the art.

Perhaps you will only work on one small part of an energy harvesting system, such as methods for RF-to-DC conversion. But you would still need to be cognizant of the whole system, in order to understand the design requirements and constraints.

The link below has all of the IEEE article titles and abstracts, for 2005 to 2013, from a search for "RF Energy Harvesting", along with a list of all of the authors and how many publications they have in this area. Reading the abstracts of some of these papers should give you a good start on your literature search.

https://ieeexplore.ieee.org/search/...ue&queryText=RF+energy+harvesting&.x=27&.y=15

 

[juni1122]

i have downloaded it all
i think it will take a while to go through it
anyother links which give up to date knowledge about the work done untill now
research papers are preferable

 

[juni1122]

it took me a long time to read all the literature review
now i am ready to do practical designing
i have chosen the hexagonal spiral array as an antenna
i want to simulate it first in hfss
can anyone guide me in simulation and designing i shall be very thannkful