The following commands will create a new device collection in SCCM 2012 (or later) with the name Foo that is configured for incremental updates, and for a weekly full refresh (on Saturday at 9pm):
$Schedule = New-CMSchedule -Start "01/01/2016 9:00 PM" -DayOfWeek Saturday -RecurCount 1
$Collection = New-CMDeviceCollection -Name Foo -LimitingCollectionName "All Systems" -RefreshType Both -RefreshSchedule $Schedule
Similarly, to create a collection with a daily full refresh (at 11pm), and no incremental updates:
$Schedule = New-CMSchedule -Start "01/01/2016 11:00 PM" -RecurInterval Days -RecurCount 1
$Collection = New-CMDeviceCollection -Name Bar -LimitingCollectionName "All Systems" -RefreshType Periodic -RefreshSchedule $Schedule