Hello everyone

I am currently working on a project as a student where I need to transfer power wirelessly.
I need help finding a circuit that can convert a DC signal to AC and transfer 5W from one coil to another.
Input is 15V DC.

I came across an osciallator called "Royer osciallator" which should be able to produce high power on the output coil but I must admit that I do not fully understand it.

Does anyone have an idea to a circuit that can help me transfer 5W from DC to AC via an inductor?

Thanks a lot!

 

How far apart are the transmitter and receiver? Do you really need wireless transfer, the losses, the complications or it it just something neat.

 

How far apart are the transmitter and receiver? Do you really need wireless transfer, the losses, the complications or it it just something neat.

Hello. We are making a wireless phone charger and my responsibility of the project is to convert 15V DC to AC and make the transmitter.
The transmitter and receiver will be placed very close. maximum 0,5cm apart I believe.

edit: I need to send as much power as possible. Ideally we would like 6W but 5W is fine as well

 

I wouldn't want to charge my phone that way. If I had a phone. Too many people today always run their battery down.....before charging. By plugging the phone in......you can use phone and charge.

Can one use a phone while wireless charging? Wireless charging requires another platform and more area.....takes up more precious space.

It's not the connected wire that takes time to charge. It's the battery. A phone that could stay in operation for the time it takes to change a battery......would be a great feature.

 

I wouldn't want to charge my phone that way. If I had a phone. Too many people today always run their battery down.....before charging. By plugging the phone in......you can use phone and charge.

Can one use a phone while wireless charging? Wireless charging requires another platform and more area.....takes up more precious space.

It's not the connected wire that takes time to charge. It's the battery. A phone that could stay in operation for the time it takes to change a battery......would be a great feature.

It is a project we are doing student... It doesn't matter if it is practial or not that is not the point. The point is learning about wireless transfer.

 

Hello. We are making a wireless phone charger and my responsibility of the project is to convert 15V DC to AC and make the transmitter.
The transmitter and receiver will be placed very close. maximum 0,5cm apart I believe.

edit: I need to send as much power as possible. Ideally we would like 6W but 5W is fine as well

You should be able to use a simple induction charger circuit like this.
http://www.nutsvolts.com/magazine/article/august2013_Bates

 

Something worth a shot is a Google of "Electric toothbrush charging circuit" and then take a look at Images for Electric toothbrush charging circuit That should give you an idea of how wireless charging circuits work. Inductive coupling through air really limits the power but it does work.

Ron

 

You might find the information here useful, at least as background:

http://batteryuniversity.com/learn/article/charging_without_wires

A more impressive project, IMNSHO, would be to forget about the phone charger -- once you've transmitted the power the phone charger is off-the-shelf (unless you are doing all of the circuitry for the phone charger including temp and state of charge sensing and all that). Instead, have your project measure the efficiency for a few different designs of wireless power transfer systems under various conditions, such as how well aligned the transmitter/receiver are and how much power is actually being used. More engineering, more science, more analysis -- better project all around.

 

I wouldn't want to charge my phone that way. If I had a phone. Too many people today always run their battery down.....before charging. By plugging the phone in......you can use phone and charge.

Can one use a phone while wireless charging? Wireless charging requires another platform and more area.....takes up more precious space.

It's not the connected wire that takes time to charge. It's the battery. A phone that could stay in operation for the time it takes to change a battery......would be a great feature.

Hi,

The only advantage i see for wireless charging is the ability to charge without having to rely on a physical connection to make the current flow get to the battery. Connectors can be a problem because they wear out and with the smaller USB connectors being used these days they can get screwed up and break off for example. I've read about horror stories like that.

But in spite of that i am still almost 100 percent against wireless charging, as per state of the art as it exists today, because it is not efficient enough. I say "almost" because i believe there is much room for improvement both physically and electrically. I may even try to improve this technology myself as i havent done anything really that important in years now Maybe start a group project here as there are several approaches that can be explored yet.

There is also a government agency that may start to argue against the use of this technology if it does not improve. I've have to look up the name again, but it is mostly concerned with the 'green' aspects of all technology. We went through the change from regular transformer/rectifier/cap wall warts to more efficient regulated higher frequency wall warts after studies had shown really nasty power wasting with the older technology, so we dont need to truncate that improvement by slapping together a new technology that wastes even more power just because it has the appearance of making it more convenient for people. Time will tell what happens in this area i guess.

 

Love this from your link @WBahn