I have been having the same problem with wireless connection

If you go to control panel - network connections - right-click on the wireless connection and choose Properties.
click on the Configure button - under "Power Management" there was a tick in a box beside the comment "Allow the computer to turn off this device to save power"
I removed the tick and saved.

Since doing that my connection has not dropped off once.

Well some other reasons you are facing this issue are:

1)Your Router Is Overburdened By Heavy Network Use :
your router may be working fine but is just not the right match for your networking needs. Don’t limit your internet use because your router can’t handle it

2)Your Wi-Fi Signal Is Weak or Doesn’t Extend Far Enough:
Wi-Fi connections can easily drop when the connected device is located near the edge of your network’s wireless signal range.

Upgrading your router to one that is more powerful can definitely help you.

Well you can get more information about WIFI connection at:
https://zappedia.com/wifi-internet-connection/

3)You’ve Got Too Much Wireless Interference:
Your router isn’t the only device in your house emitting a signal. Several household items like Bluetooth devices, microwaves, TVs and cordless phones are pumping out radio signals that can interfere with your Wi-Fi network signal when they are in use.

Moving your router away from devices like these is an easy solution

4)Your Firmware or Drivers Need An Update:
Your computers connect to a Wi-Fi network using a device driver and your router creates a Wi-Fi signal based on its firmware. Network drivers and firmware can occasionally affect your network connection if either/both requires an update.

Check your computer for any driver updates and install new firmware for your router from the product page on the manufacturer’s website.

You can read some amazing articles at:
https://: https://zappedia.com

I suggest update the firmware of D7 http://www.tp-link.com/faq-652.html

I have exactly the same problem in that the 5GHZ wireless SSID disappears and I lose network connection.

My firmware details are:

Device Information


Firmware Version:
1.8.0 0.9.1 v0051.0 Build 170511 Rel.51715n


Hardware Version:
Archer D7 v1 00000000

I learned that tp-link has beta firmware for this 5G disappear issue, suggest you guys contact the support team at [EMAIL="support@tp-link.com"]support@tp-link.com[/EMAIL] for the beta

Already have the Beta. Seems to be stable. Few bugs though and it has confidential test version plastered all over it