Direct-Coupled IT Load

A DC load for use in a data center, the load comprising:

• a motherboard including at least one digital processor operative to process data received over a network;
• a DC bus configured to deliver operating power to the motherboard, the power being received from a power source connected across the DC bus;
• and
• an uninterruptible power supply (UPS) integrated with the DC load, the UPS comprising:
• a battery circuit configured to operatively connect a battery across the DC bus during a fault condition in which an AC input voltage signal falls outside of a normal operating range;
• an AC-to-DC rectification stage comprising a PFC-boost AC-to-DC conversion circuit configured to convert a substantially unconditioned AC input voltage signal to a single DC output voltage signal across the DC bus when the AC input voltage signal is within the normal operating range, wherein the AC-to-DC conversion circuit is configured to regulate the DC output voltage signal to a voltage level above and substantially near a maximum nominal charge voltage of the battery;
• and
• a controller configured to selectively activate the AC-to-DC conversion circuit to resume supplying operating power to the DC load in response to a signal that indicates that the AC input voltage signal has returned to the normal operating range.

A method of providing uninterruptible power to at a motherboard in a data center, the method comprising:

• connecting a DC bus to supply a single DC voltage to at least one DC load, each DC load comprising at least one digital processor;
• operating a PFC-boost AC-to-DC converter when an AC input voltage signal from the electric utility grid is within a normal voltage range, the operating step comprising:
• converting the AC input voltage signal to a DC voltage on the DC bus, wherein the converting step comprises the only AC-to-DC rectification of electric power generated by the electric utility grid and delivered to the DC load;
• regulating the converted DC bus voltage to a set point voltage, the set point voltage being substantially close to a voltage in a nominal voltage range for a back-up battery;
• in response to detecting a fault condition of the AC input voltage signal, connecting a battery circuit directly across the DC bus to enable the back-up battery in the battery circuit to provide operating power to the DC load such that the DC load continues to operate for a period of time after detecting the fault.