Hi Vikash,
There is not a way to schedule PAM process backups in Process Automation. If you need to backup one or processes in a specific folder you would need to right click on the folder or process and export it to xml as you stated. If you need to backup the entire orchestrator, you may want to work with your Network Admins to come up with the best plan needed for your site to backup the system.
1. Backup entire PAM install folder.
2. Backup DB.
An automated backup of the processes through Process Automation would be an enhancement. Please feel free to open an "Idea" through the Process Automation communities. Thank you.