17.5fps is very fast gearing for a 130 pound robot. It is not surprising that you are hitting the brown out protections at the end of the matches.
If we didn’t put good batteries in our robot last year we would hit brown out protection near the end of matches. We were geared at about 16.3fps.
You might consider changing your gearing if possible. If you are using Talon SRXs it would be a good idea to enable current limiting. This would help mitigate the issue as well.