Outlook does not support CalDAV, and therefore it is also not possible to sync with PH Cloud (or any other CalDAV implementation).
There's a few plugins though that add this functionality to outlook:
Bynari WebDAV collaborator is a very active, non-free plugin for outlook. It works well with PH Cloudand syncs contacts, calendars and tasks.
iCal4OL is another (non-free, but it has a trial). I have personally not tested it so if it worked with PH Cloud, but we have had good reports.
Open Connector is a free plugin for Outlook that is supposed to provide support for this, but the project appears unmaintained since 2008, and I personally haven't gotten it to work. If you did, let me know how.