Hello,
as part of an effor to clean up matlab answers, this response is being made even though it is far too late to be of use to the asker:
You can ignore zero-sequence to get a basic idea of how your system will perform, especially if it is balanced, however, instead of leaving it at zero, you might consider making the same as your positive sequence (or a bit smaller) This is not ideal however. There are tools to help estimate these parameters if you know your conductor's geometry.
Regards,
Joel
