I think there has been a confusion.
Where are you getting 3 from ? (the image is just an example, not suggesting that your series will be identical)
A PV Panel with open circuit voltage of 21.5 Volts will have its maximum power point voltage around 17.5 Volts.
80 Watts peak at approximately 17.5 Volts = approximately 4.5 amps
If you put 2 of these panels in series you will have a string of
- Open circuit voltage = 43 Volts
- Maximum power point voltage = 35 Volts
- String current at maximum power = 4.5 Amps
Currently with these 2 panels you only have 160Wp. You have 20 panels in total which you want to use to have a total 1600 Watts peak.
Place 10 of these strings in parallel (protect your strings with a fuse, 10 amps per string for example) and you will have the combination you are looking for.
- Array Open circuit voltage = 43 Volts
- Array Maximum power point voltage = 35 Volts
- Array current at maximum power = 45 Amps
But if it is good enough for your inverter is all just guess work, because we don't know your inverter characteristics.
Anyway, from your comment looks like you already have your answer, best of luck with your tests.