It's not possible to answer definitively: What model system (Inspiron 3551, 5559, etc.)? Is this on AC power or battery? Does the system correctly recognize the AC adapter (F2 at powerup to check in setup;  make sure the adapter is reporting its power output, and not showing "unknown"). Is the DC plug firmly connected to the system's jack or USB-C port?  
i have dell laptop and facing automatically shutdown issue. i install the new window10 but again the same issue is facing after few minutes laptop shutdown auto.  no over heating problem  
laptop