Hello there! Sorry to hear about your iPad it sounds like the iOS is having issues managing your power. We will need to do the following steps to reinstall the iOS. This will delete everything on your ipad however if you are signed into iCloud all your information will be restored. You will need a mac or pc with itunes installed to complete the following steps.
if you do not have itunes you can get it from the link below.
Make sure the iPad's screen is blank and no logos are present
Restore with itunes. Once the iPad finishes restoring you can sign in with your icloud email and password ***** all your information will be sync'd