DIY 1kW MPPT Solar Charge Controller
instructables.com
DIY 1kW MPPT Solar Charge Controller
1–10 of 12 posts
Re: DIY 1kW MPPT Solar Charge Controller
#2Re: DIY 1kW MPPT Solar Charge Controller
#3This is incredible! It would be the front page if HN hadn't become Reddit 2.0
Great work!
I'm kinda sad nobody has replied in hours :( . My dad was an ELE and this is beyond the quality of most professional work as far as research and implementation.
As a dev that knows electronics fairly well, your project is great OP
Re: DIY 1kW MPPT Solar Charge Controller
#4This is a fantastic instructables
Re: DIY 1kW MPPT Solar Charge Controller
#5This is really cool! Does anyone understand the physics well or have a reference? I don’t fully understand why there’s a maximal power point.
Re: DIY 1kW MPPT Solar Charge Controller
#6This is really cool! Does anyone understand the physics well or have a reference? I don’t fully understand why there’s a maximal power point.
Power is voltage times current.
With an open circuit (infinite resistance load), the voltage is a finite number but current is zero, so power is 0.
With a short circuit (zero resistance load), voltage is 0 and current is some finite number, so again power is 0.
With loads in between short circuit and open circuit (i.e. some finite nonzero resistance), both voltage and current are nonzero, so nonzero power is produced.
One or more of those load points will result in a maximum in the power production curve. With real PV cells and real light, one point is the maximum at any given time.
Re: DIY 1kW MPPT Solar Charge Controller
#7This is really cool! Does anyone understand the physics well or have a reference? I don’t fully understand why there’s a maximal power point.
A crude explanation is that solar panels are basically a Constant Current source.
They have a maximum Voltage when open circuit, and a maximum Current when shorted.
And the maximum power point is somewhere between those two extremes.
Exactly where depends on various conditions, like the strength of the sunlight (clouding, etc).
Re: DIY 1kW MPPT Solar Charge Controller
#8This is really cool! Does anyone understand the physics well or have a reference? I don’t fully understand why there’s a maximal power point.
Power is voltage times current. With an open circuit (infinite resistance load), the voltage is a finite number but current is zero, so power is 0. With a short circuit (zero resistance load), voltage is 0 and current is some finite number, so again power is 0. With loads in between short circuit and open circuit (i.e. some finite nonzero resistance), both voltage and current are nonzero, so nonzero power is produced…
Seems like you are implying there's a non-real solution to that curve's maximum as well, which makes sense. Obviously directly these aren't useful, but I wonder if there are any situations where imaginary solns might also be helpful to know?
Re: DIY 1kW MPPT Solar Charge Controller
#9Earlier quoted context omitted.
Power is voltage times current. With an open circuit (infinite resistance load), the voltage is a finite number but current is zero, so power is 0. With a short circuit (zero resistance load), voltage is 0 and current is some finite number, so again power is 0. With loads in between short circuit and open circuit (i.e. some finite nonzero resistance), both voltage and current are nonzero, so nonzero power is produced…
Seems like you are implying there's a non-real solution to that curve's maximum as well, which makes sense. Obviously directly these aren't useful, but I wonder if there are any situations where imaginary solns might also be helpful to know?
I think they're just hedging for the fact that there could theoretically be multiple local maxima, but in practice the current-voltage curves of PV panels are boringly well-behaved and so there's just one maximum.
(In electronics if you find complex numbers they're usually being used as shorthand for complex exponentials via a Laplace transform — in this case, an imaginary or complex solution would mean that the PV panel has some kind of weird resonant behavior — again, unlikely to be the case for any panel you actually have.)
Re: DIY 1kW MPPT Solar Charge Controller
#10Impressive work. Not often do you see execution so well documented.