This feature is in maintenance mode, meaning that it might be removed in a future version of SQL Server. The SQLPS module should be used instead.
The replacement seems to be sqltoolsps.exe.
Apparently, even the SQLPS is now deprecated in favor of the SQLServer module.
c:\> sqlps
PS> cd sqlserver:\
PS> ls
PS> cd SQL
PS> ls
PS> cd $env:COMPUTERNAME
PS> ls
PS> $wmi = (get-item .).managedComputer
PS> $sqlServerInstance = $wmi.services['MSSQLSERVER']
PS> $sqlServerInstance.stop()
PS> $sqlServerInstance.start()