US Patent 11569751 Systems and methods for combining power sources in datacenters

A device for providing power to a server rack includes a first AC input port, a second AC input port, a first relay, a second relay, and an output port. The output port is electrically connected to both the first AC input port and second AC input port. The first relay is electrically between the first AC input port and the output port, and the second relay is electrically between the second AC input port and the output port. The first relay and second relay are configured to compare a first phase of a first voltage from the first AC input port to a second phase of a second voltage from the second AC input.