The voltage in the scope is coming out to be zero because of a short in your circuit. So, its effectively measuring the short circuit current (which is why the current is nonzero) and the short circuit voltage (zero).
To fix this, we can remove the short. I have simplified the Model by considering a Variable Resistor block as load and the rest of the connections are kept the same. The cell temperature is set from mask of the PV Array from the advanced tab, so we do not need to use a Constant block. To plot the characteristic curves, I have used XY-Graph blocks. This is shown below:
The plots we get as output are shown below:
I-V Curve:
P-V Curve:
Hope it helps!
