Using a FPGA to run a single axis solar tracking system.

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For my electrical engineering senior cap stone I'm using a FPGA ( Spartan 3e starter kit) to try and run a vertical stepper motor to move two solar panels(that are fixed side by side) horizontally.

My problems so far is how am I going to measure the output voltage of the solar panels and input the value into the FPGA so it can measure the value, and how do I store the value once I get them. I plan on using these values to know how to turn the motor so the panels are at optimal position for power generation.

Also how do I control/move the stepper motor? Am I going to have to get a controller/driver for it and interface the FPGA with it? or is there a way to control the motor with just the FPGA? I'm trying to keep cost down, but also work load.

Are you asking for professional consultation from a qualified electrical engineer?

FPGA is just overkill for this kind of application. Probably an 8-bit MCU like Atmel ATmega88 etc.. will do just fine. And if not any 32-bit ARM cpu like STM.. series will do it.

To input the voltage value from the solar panel is done by wiring it to an A/D on the MCU. And adjust the scale with Vref, resistor divider etc.

As stoneturtle says, an FPGA is not an ideal solution for this problem. Take a look at the Arduino. It is based on an Atmel microcontroller and comes with a range of useful libraries that take care of running steppers, reading ADCs etc. However, if the aim is more to find a use for an FPGA rather than the simplest solution then it can be done.

Basically you need an analog to digital converter to read the voltage. You can drive the motor directly from the FPGA using two H-bridges but it is easier to use a dedicated controller chip or module. Do some research on steppers. There is loads of information out there. The same goes for analog to digital converters.

aside from the FPGA this is like electronics 102.
single axis is easy, two limit switches, stepper driver... you're going to burn up more joules in the fpga than the steppers!
its not even worth trying to dither the solar panel angle to get the most sun, even 5 degrees off center and the power drops like 2% or less, you'll be hunting for the highest solar output all day long.
all the micro proc has to do is remember how many steps it takes to swing the panel from sun up to sun down.
when the panel is installed just set the date and latitude....

/grumbles about why i'm not getting paid yet...
here's what i did today.


now i just need to figure out how to build an electromagnetic beer bottle capper.
That would be sure to hit hackaday.

well, we started out trying to make an electromagnetic induction launcher
didn't get anywhere with that because the coils kept exploding, a piece of which cut my lip open..
the photo is just a copper pipe cut in half after half a million amps flowing around in a circle within it, flattened it.

there's hundreds of youtube videos of people cutting alumium cans in half with a coil wrapped around it. same thing essentially.

Ah I see. Yes, I guess half a million amps would do some pretty odd things to a pipe . I've always wanted to have a go at coin shrinking. That looks like fun. Destruction, dangerous amounts of electricity and loud explosions - what more could you want?

What caps are you using and how are you switching them?