Try the following...
1. You would need to go into "Control Panel" then click on "Power Options".
2. Next click on the "Change plan settings" link next to whichever plan you have selected.
3. On this next screen click the "Change advanced power settings" link.
4. You will get a new window listing all the different things/options that can be changed to not do anything, power off, sleep and hibernate. Go through each of them to make sure none are set to turn it off/sleep/hibernate unless it is for a time when you want it to. Like when closing the lid.