runspace = System.Management.Automation.Runspaces.RunspaceFactory.
CreateRunspace(psConnectionInfo);
runspace.InitialSessionState.ImportPSModule(new[] { "ActiveDirectory" });
runspace.Open();

Pipeline pipeline = runspace.CreatePipeline();

        PowerShell powershell = PowerShell.Create();
        powershell.Runspace = pipeline.Runspace;

        powershell.Runspace.InitialSessionState.ImportPSModule(new[] { "ActiveDirectory" });