Re: [TRNSYS-users] Photovoltaic arrays

[Anton Driesse <driessea@post.queensu.ca>]

Hi David,

I like the fact that there are different outputs available 
simultaneously so I can choose from different operating modes.  I am 
trying to model an array with multiple units under under different 
conditions, where a single unit might experience some extreme 
conditions.  Is V permitted to go negative?

Would you also clarify the following comment from IISiBat, which refers 
to parameter 18:

"In this mode of Type94, the slope of the IV characteristic at the short 
circuit current point is positive, effectively modeling single or 
polycrystalline silicon photovoltaic panels."

I am having trouble understanding where the positive slope comes from.

Thanks!

Anton


David Bradley [SEL] wrote:
> Dear Anton,
>  Neither Type94 nor Type180 model electrical energy absorption. In both 
> models, if the load voltage is greater than the array's open circuit 
> voltage, the power output of the array is set to zero. Neither of the 
> two models has an input for the current across the array (these are 
> outputs, not inputs). I might also mention that Type94 has two power 
> outputs. One is the power at the maximum power point, a value that is 
> independent of the user supplied load voltage. The other is the "array 
> power." This second output is dependent on load voltage and represents 
> the intersection point of the array's current voltage characteristic 
> curve and the load voltage.
> Kind regards,
>  David
>
>  >Do either TYPE 94 or 180 permit a PV array to absorb electrical energy 
> and/or correctly model this?  (V > Voc and I < 0)
>  >
>  >Anton Driesse