Running SSIS ETL Package with Invoke PowerShell

I am having trouble invoking a PowerShell script in Studio, to run an SSIS package. The script runs fine on our server where the SSIS package lives, but will not run in Studio. I tried hard-coding the server username/password in the script as a test but that did not work. My question is, how to connect to SQL server within the PS script to run the SSIS package?