Windows Update Powershell Commands
From DFWLPiki
The PSWindowsUpdate set of commands is required.
Install the PSWindowsUpdate module:
Install-Module -Name PSWindowsUpdate –Force
Apply all available updates:
Install-WindowsUpdate -AcceptAll
List all available updates
Get-WUList
Show Updates sources and which is default (Desired state is usually "true" for Windows Server Update Service)
Get-WUServiceManager