This community PowerShell module created by MVP Ryan Andorfer will give you the ability to interact with Orchestrator Web Service trough PowerShell. Here is full description from the author:
A set of PowerShell cmdlets for interacting with the System Center 2012 Orchestrator web service, complete with help documentation. Supports invoking runbooks with parameters and the parameters can have html characters! This PowerShell Library contains the following functions
Name
—-
Get-SCOEvents
Start-SCORunbook
Stop-SCOJob
Get-SCOMonitorRunbook
Get-SCORunbookServer
Get-SCOSubfolders
New-SCOWebserverURL
Get-SCOJob
Get-SCORunbook
You can download the PowerShell module from TechNet Gallery.