All recent versions of Microsoft Office programs come with a feature called AutoRecover. The AutoRecover feature is enabled by default but only saves every 10 minutes.

AutoRecovery of Office files every ten minutes automatically saves the documents you're working on in Office and restores the file for you in the event of a crash or if you shut down your computer without saving. But sometimes ten minutes is too long.
And surely all of you have experienced losing a file due to an unplanned shutdown and then recovering it and not remembering how you had edited it. Losing ten minutes of work may not be the worst thing that can happen to someone, but it is not the most pleasant either.
What if you changed this setting and now Office applications automatically recovered every minute? Note that this should not be confused with AutoSave, which performs the same task, but only when working on a file stored in OneDrive.
AutoRecover automatically saves the file you're working on in the background. And because it does so in the background, you don't see any messages or notifications on your screen. When you start the same Office program after a crash, the program offers to restore the file that was automatically saved, through the AutoRecover feature.
Make Office Word, Excel, and PowerPoint Save Files Every Minute
NOTE: In this example, we'll be making changes to the Word program. You can follow the same instructions to make changes to Excel, PowerPoint, and other Office programs, too. Remember, you have to make the change in each Office program separately.
Step 1: Open Word and click the “File” menu and then click the “Options” button to open the Options dialog box.
Step 2: In the left pane, click the “Storage” tab.
Step 3: In the right pane, in the field next to “Save AutoRecover information every,” set the box to 1 minute to force the Office program to save the data every minute. Click OK.

According to Microsoft, entering a lower number may slightly slow down the Office program. However, this depends on your computer and its capabilities. If you notice that you think your Office program has slowed down, change the value to 2 or 5.
