Once you have been granted a permanent visa it has an initial five (5) year validity period. This validity period is essentially a travel facility. If you remain in Australia beyond the five years your permanent residence does not expire, only your ability to depart and then re-enter Australia as a permanent resident is affected.
To obtain a new five (5) year travel facility (called a resident return visa, or RRV) the basic criteria is that you have spent at least two (2) years out of the last five (5) physically present in Australia as the holder of a permanent visa
If you cannot meet the ‘2 in 5’ requirement you may be eligible for a resident return visa with one year travel validity. As noted above, if you remain in Australia beyond the one year validity period your permanent residence does not expire, only your ability to depart and then re-enter Australia as a permanent resident is affected.
To meet the requirements for the one year RRV you must demonstrate that you have substantial ties to Australia that are of benefit to Australia. Substantial ties can be under any of the following:
Permanent residents who have less than 2 years’ physical presence in Australia and who have not yet established substantial ties of benefit to Australia may be eligible for a three month RRV. For example, you may have settled in Australia when nearing the end of your migrant travel facility and need to travel overseas before you have established substantial ties.
As above, if you remain in Australia beyond the 3 month validity period your permanent residence does not expire, only your ability to depart and then re-enter Australia as a permanent resident is affected.