Are you using Windows built-in utility or TP-LINK utility to connect Wi-Fi?
With either of them, there is an option to connect automatically. It won't work?
In profile list, it is not saved there?
How about signal strength showing on your PC?

Thanks for the quick response!!
To answer your questions:
I am using TP-Link utility the option to connect automatically is on and the profile is on my saved list. Also the signal strength is 100% almost all the time and if it drops it goes down to 98%.
In spite all of these at random times it keeps disconnecting (up to 8 times/6hours).After i write the password it reconnects but i don't think this is how it should work!!

Try to update chipmaker's driver(RTL8192CU) and connect with built-in utility on Windows 7..
http://www.realtek.com.tw/downloads/downloadsView.aspx?Langid=1&PFid=48&Level=5&Conn=4&ProdID=277&DownTypeID=3&GetDown=false&Downloads=true
http://www.tp-link.com/en/faq-306.html