Implement maximum power for IV sweep for solar cells in the field using CompactRIO

[illuminance meter]

Hi Everyone,

I'm sorry. Has anyone ever experienced on implementing maximum power point for solar cell using CompactRIO? I have NI 9074, NI 9221 (Voltage) and NI 9227 (current) modules at my system and I'm using Labview RT. There's a tutorial on MPPT using cRIO at the website http://zone.ni.com/devzone/cda/tut/p/id/8106   .However, it doesn't have an example code to get started with or explanation to configure the system. Anyway, how can I possibly implementing it on my machine? Do I need an additional module or a third party hardware to implement it? Please advice.

Thanks,

Akram 

[Ben.h]

Hi Akram,

Are you trying to implement a complete solar tracking system or just trying to build a VI that carries out a IV sweep? What are you using the cRIO for? You could write a code that finds the maximum product from the current and voltage hence the maximum power point. Then continuously find the maximum power point by comparing the different products of the voltage and current compared with the previous maximum power point.

Regards

Ben Hartrick

NI AE

[illuminance meter]

Hi Ben,

How are you? I'm sorry and thanks for your response. I'm actually try to measure the current (Isc) and voltage (Voc) curve from a solar module on the building roof to generates the maximum power point (Pmax) (Outdoor measurement). The curent (sourcing) and the voltage will be at 1st quadrant.

( http://zone.ni.com/devzone/cda/tut/p/id/7230  ) However, I couldn't find any cRIO modules that are able to have 4 -Quadrant operation. ( https://www.ni.com/en-us/shop/model/pxi-4130.html ). Anyway, Is it possible to write a code to measure the IV curve and Pmax (1st quadrant) using my existing cRIO modules only? Or do I need to have a thrid party hardware ( i.e keithley) to ? Please advice.

Best Regards,

Akram

[Ben.h]

Hi Akram

I have been looking at the specifications for both the modules you are using with your cRIO

https://www.ni.com/en-us/shop/model/ni-9227.html

Both modules will produce negative values and therefore all 4 quadrants of the solar module can be displayed in LabVIEW.

You can use LabVIEW to convert all values read from both modules to positive values so that you are effectively working in the first quadrant all the time and hence real values of maximum power can be found. There are functions in the maths palette which can facilitate this need. I have written some example coe for you which I have attached as a VI.

Kind Regards

Ben Hartrick

Applications Engineer