"OEG Policy Center is intended for managing policy deployments across multiple Oracle Enterprise Gateways (multiple-gateway policy management). OEG Policy Center manages policy migration between development, staging, and production."
It is essentially a process you start ala the gateway itself and you then connect to it via Policy Studio. Here I have 2 OEG instances and policy center started.
I can then start Policy Studio and connect to Policy Center -
Note the default policy center port is 8060
As you can see, I have added the 2 OEG instances to the "process" list
I added a new user and a couple of Alerts to the Test instance. Now I export the configuration, saving to file exportUsers.xml
Return to the main Policy Center screen
I select the "production" instance