My name is Ajit Singh and i work for dell social media and community.
I am afraid a USB 2.0 cannot be upgraded to USB 3.0. First you need a motherboard which can support USB 3.0 to get the maximum out of it and secondly both the receiver device and sending device should be on USB specification. One more point is, if you check connector on USB 2.0 and USB 3.0 they are different, so if you will try to connect a USB 3.0 cable on USB 2. 0 port it will not fit.
So it is a must to get a new system which is already configured to USB 3.0.