High Power USB Charger current limiting ( +40 Watts )

[Richard Crowley]

As with previous USB versions, USB 3.0 ports come in low-power and high-power variants, providing 150 mA and 900 mA respectively, while simultaneously transmitting data at SuperSpeed rates.[24] Additionally, there is a Battery Charging Specification (Version 1.2 – December 2010), which increases the power handling capability to 1.5 A but does not allow concurrent data transmission.[21] The Battery Charging Specification requires that the physical ports themselves be capable of handling 5 A of current[citation needed] but limits the maximum current drawn to 1.5 A.

And for USB 3.1....

Native Type-C connectors support power currents of 1.5 A and 3.0 A over the 5 V power bus in addition to baseline 900 mA; USB Power Delivery 2.0 profiles are optionally supported.
http://en.wikipedia.org/wiki/USB#USB_3.1

You seem to be designing something that uses USB connectors at higher currents than they were designed for. Beware of the safety/heat/fire implications.