Dynamic power management based on measurements of usb power from aircraft power system to passenger electronic devices

A method by a power management system including a plurality of power monitor and control circuits connected to power outputs configured to supply power to user electronic devices (UEDs), where each of the power monitor and control circuits are configured to measure actual power supplied through one of the power outputs to one of the connected UEDs and to responsively generate a measured power indication, the method comprising:

• for each of the UEDs, negotiating with the UED an agreement for a subscription power level that the UED is authorized to be supplied by the power management system, wherein the negotiations allow an oversubscription state by agreeing to subscription power levels for the UEDs that when combined into a total subscription power level exceeds a maximum power supply capability of the power management system, wherein method controls power level supplied to the connected UED based on the subscription power level for the UED and/or based on a command from the power manager circuit,
• for each of the UEDs, determining a present actual power usage of the UED based on the measured power indication from the power monitor and control circuit measuring actual power supplied through the power output connected to the UED,
• determining a present total actual power usage of the UEDs based on a combination of the measured power indications from the power monitor and control circuits, and
• responsive to determining the present total actual power usage of the UEDs exceeds the maximum power supply capability of the power management system minus a first threshold offset, renegotiating an agreement with at least one of the UEDs for a lower subscription power level that the at least one of the UEDs is authorized to be supplied so that the total actual power usage of the UEDs will cease exceeding the maximum power supply capability of the power management system minus the first threshold offset.

A computer program product comprising a non-transitory computer readable medium storing instructions executable by at least one processor of a power management system including a plurality of power monitor and control circuits connected to power outputs configured to supply power to user electronic devices (UEDs), where each of the power monitor and control circuits are configured to measure actual power supplied through one of the power outputs to one of the connected UEDs and to responsively generate a measured power indication, the instructions when executed by the at least one processor perform operations comprising to:

• for each of the UEDs, negotiate with the UED an agreement for a subscription power level that the UED is authorized to be supplied by the power management system, wherein the negotiations allow an oversubscription state by agreeing to subscription power levels for the UEDs that when combined into a total subscription power level exceeds a maximum power supply capability of the power management system, wherein operations control power level supplied to the connected UED based on the subscription power level for the UED and/or based on a command from the power manager circuit,
• for each of the UEDs, determine a present actual power usage of the UED based on the measured power indication from the power monitor and control circuit measuring actual power supplied through the power output connected to the UED,
• determine a present total actual power usage of the UEDs based on a combination of the measured power indications from the power monitor and control circuits, and responsive to determining the present total actual power usage of the UEDs exceeds the maximum power supply capability of the power management system minus a first threshold offset, renegotiate an agreement with at least one of the UEDs for a lower subscription power level that the at least one of the UEDs is authorized to be supplied so that the total actual power usage of the UEDs will cease exceeding the maximum power supply capability of the power management system minus the first threshold offset.