Solar Controllers--Don't be a Sucker! :(
Just got to say it again, how it is we are sitting here for five months off grid on solar with no problems at all (third season on solar like this), using the non-programmable, non-MPPT, solar control...
Forum Discussion
Sounds like some think that mppt excels during dawn and dusk. They think panel voltage will be available sooner. I don't share that view. It may be slightly better, but nothing to crow about.
If you look at the plot Current-Voltage PV Characteristics at various irradiance, you'll see current varies greatly when going from 1000W/m^2 to 200W/m^2. The voltage stays in a relatively narrow zone. In other words, you shouldn't have to wait very long to get a good operating voltage for pwm.
http://www.wholesalesolar.com/products.folder/module-folder/kyocera/KD135GX-LPU.html
Also, the harvesting current at these time periods is very small. How much energy does the sun have when you can look straight at it?
I don't have this data as direct sun rays are blocked at lower elevations at my test site.
Sal
If you look at the plot Current-Voltage PV Characteristics at various irradiance, you'll see current varies greatly when going from 1000W/m^2 to 200W/m^2. The voltage stays in a relatively narrow zone. In other words, you shouldn't have to wait very long to get a good operating voltage for pwm.
http://www.wholesalesolar.com/products.folder/module-folder/kyocera/KD135GX-LPU.html
Also, the harvesting current at these time periods is very small. How much energy does the sun have when you can look straight at it?
I don't have this data as direct sun rays are blocked at lower elevations at my test site.
Sal
HiTech wrote:
What does MPPT vs. PWM look like for dawn to dusk? Those ends of the graph are of interest too.
Jim
