Solar Freaks

Very neat design TonyB.

some questions, I hope they are not too stupid.

1. How do you measure such a high current on high side. Are you using some differential amp across a resistor.

2. Why cant you drive the Mosfets directly from micro pins.

rgds / techie.

Hi,
There is a high side current sense amplifier there.
Also, there is a mosfet driver, so the FETs are not driven straight from the micro controller.

Which mosfet driver are you using. I had a look at some datasheets. Most require at least 12-16 volts Vcc. With an input from 10V, and then using a regulator, how do you power up the driver.

techie

very nice !

Hi all!

I need a MPPT to ride a string of 16 solar panels 200W each, 7.52A@26.6Vmp, 469 Voc@string.

Ouput voltage at maximun load between 428Vcc to 340Vcc depending on temperature.

Could you desing FATMAX at these parameters?

I wont to use one FATMAX per solar panel.

Thank you.

I am making a solar powered RC aircraft that can run on solar power and batteries. I need to get a MPPT for our project that can regulate the power for use with lipo batteries that are 8000 mah and 11.1 volts as well as solar panels. the aircraft has to be able to switch between battery use for night flying and solar use for daytime flying and also be able to keep the batteries fully charged when not in use. Can you recommend anything that will allow me to do so? If i need other equipment other than an mppt can you please let me know.

thanks

Hi hawkstriker512,

Have you posted on rcgroups.com? They have lots of discussions on that. (I can probably jump in on your thread if you want me to.)

The first thing you need to figure out is your wing loading ratio. In straight and level flight (no wind) you can maintain altitude for a certain weight of solar panels that generate X watts/square meter only if your wing design can generate enough lift for that watt output at the propeller. You should derate by a significant percentage for: conversion of sunlight to electricity when the sun is not straight overhead, conversion from electricity to prop rotation, and conversion from prop rotation to thrust.

Post over on rcgroups.com and they will be able to help you do the math.

How do i aquire one of these MPPT's and how much is it in US currency.

Before I set out to design my own MPPT boost/buck solar charge controller, can anyone please tell me if the following is commercially available ?

An MPPT boost/buck solar charge controller with:
400<Vin<600
0<Iin<12A
400<Vout<600
0<Iout<12A
Power rating at least 4500kW
Efficiency>98%

I have searched for quite a few hours and found NOTHING. The application is simply to add another MPPT to my SMA SMC 9000TL inverter which only has one MPPT in it. I would place it between one string and the inverter's input. At that input to the inverter there would also be another string in parallel. Currently the two strings are in parallel but aren't sufficiently well balanced for my liking despite having identical conditions and panels.

Is The FATMAX available for sale? Is the design available? I have searched the forum for this information but I can't find answers. Thanks.

hi! i have taken this as my final year project in my college. can you maill me the detailed specs and coding for the same charge controller. i am impressed by the compactness of the unit. i made on a bread-board but it turned out to be huge.
pls mail me at pujan1989@gmail.com

pujandoshi wrote:hi! i have taken this as my final year project in my college. can you maill me the detailed specs and coding for the same charge controller.

At the very least you should post your design first to convince the author you have made a reasonable attempt. Finally, the submission you make at college for such a major undertaking shouldn't look too similar to the author's.