wireless power transfer

[mhowaidi]

I'm looking for inverter that I can use it in the applications to charge automated guided vehicle, this inverter should be capable to give 48V output voltage at 100kHZ.
any recommendations please.

 

[BradtheRad]

The thread says 'Wireless charging', which is suited for small batteries (hearing aid, electric toothbrush). Then there's cabled charging which you're likely to need for vehicles. (Which means this thread may need a different title.) Anyway do you wish to convert a low battery voltage to 48V?
Do you wish to obtain 48V DC or 48 VAC 100kHz?

 

[mhowaidi]

The thread says 'Wireless charging', which is suited for small batteries (hearing aid, electric toothbrush). Then there's cabled charging which you're likely to need for vehicles. (Which means this thread may need a different title.) Anyway do you wish to convert a low battery voltage to 48V?
Do you wish to obtain 48V DC or 48 VAC 100kHz?

48V AC 100kHz

 

[FvM]

Powerlevel?

 

[mhowaidi]

Powerlevel?

1.8kw

 

[BradtheRad]

Over a kW...My quick search leads to websites that present wireless charging of industrial batteries. The idea appears legit although power transmission at high levels seems too good to be true. Wireless charging promises so much and is in such huge demand, yet even today we need massive cables to do ordinary charging. A system just to light an LED (a few mW) through the air is a challenge to build. Youtube has videos demonstrating this. The principle has two air-coils close together...

Oriented sort of like an loosely-coupled transformer. Run one coil (sender) at high frequency. Tune the other coil (receiver) to be most sensitive to oscillating at that exact frequency.
My surmise is that industrial usage involves scaling this concept up to large coils of thicker wire. Many Watts of electricity must be conveyed to the sending unit. I have a hunch the price is more expensive than solar power for example.

 

[decook1110]

This is a subject I'm following, we're planning to use PSFB inverters to drive parallel 85kHz WPT system inverters.

This link has a very good presentation from the University of Aukland on power electronics for WPT. What I like about the UofA presenstation is its breakdown of different topologies and exercised in spice simulation software.

Like the other responders in this thread I'm still not clear exactly what is being specified. If this is for a 48volt 100kHz AC waveform and 1.8kW of power, what is the final rectified DC voltage level in the vehicle? What coupling factors (min-max) are being expected in this application?

 

[BradtheRad]

I think the heart of your experimental approach is similar to making an old-fashioned 'crystal' radio. These run on no batteries yet harvest a broadcast out of the air and play it in headphones, all using power from nowhere but the airwaves. Suppose you place a simple coil near your simple radio receiver (relying on near-field effect, not far-field effect), seems to me you want to play a strong continual sine tone at the exact resonant frequency through the simple coil, so it's harvested by your homebrew radio receiver.

Your link (Auckland) is an excellent source of info. To me the big (and most rewarding) hurdle is getting power through the air. I would focus on schematics pages 28 & 32. Once I optimize my coil setup I'd work on building conventional equipment upstream and downstream of those coils.

The receiver circuitry must be the kind that runs on tiny volt levels ('Joule thief' design, or blocking oscillator design.) These make use of small coils or transformers. I've made such projects to run on 0.7 VDC. Follow this with impedance-matching circuitry which makes best use of volt and Ampere ratios. Illuminate one led and your colleagues will say that's got 'Wow factor'.