Method and apparatus to provide platform power peak limiting based on charge of power assist unit

A method, comprising:

• coupling a power supply unit to a power rail of an information handling system, wherein
• the power supply unit is configured to provide up to a maximum power (PAvailable)
• to a load of the information handling system;
• coupling a power storage element of power assist unit of the information handling system to a converter of the power assist unit:
• coupling the converter to the power rail;
• receiving, by power assist enable logic gates, a power-OK signal from the power supply unit and a constant-current signal from the power supply unit;
• providing, by the power assist enable logic, an enable signal to the power assist hardware;
• in response to receiving by the power assist unit the enable signal,
• determining, by a controller of the power assist unit, that a charge level on the power storage element is above a peak charge level threshold;
• receiving, by the controller, a current level indication indicating a current provided to a load of the information handling system in response to determining that the charge level is above the peak charge level threshold;
• directing, by the controller, the converter to provide power from the power storage element to the power rail when the charge level is above the peak charge level threshold;
• directing, by the controller, the converter to charge the power storage element at a maximum charge rate (CR) from the power rail when the charge level is below the peak charge level threshold, wherein the maximum charge rate (CR) is given as:
• CR=PAvailable−PBudget
• where (PAvailable) represents a maximum available power based upon the current level indication and PBudget represents a power budget for the information handling system;
• providing a charge level indication that indicates an amount of charge on the power storage element;
• receiving, by a baseboard management controller of the information handling system, the charge level indication;
• and
• setting a peak power limit for power consumed by the load based on the charge level indication.

An information handling system, comprising:

• power supply configured to provide a power rail to power a load of the information handling system, and to provide a current level indication indicating a current provided to the load by the power supply wherein the power supply unit is configured to provide up to a maximum power (PAvailable) to a load of the information handling system;
• power assist unit coupled to the power rail, the power assist unit including:
• a power storage element;
• a converter coupled to the power storage element and to the power rail;
• and a controller;
• power assist hardware enable logic gates configured to receive a power OK signal from a power supply unit and a constant-current signal from the power supply unit, and to provide an enable signal to the power assist unit based upon the power-OK signal and the constant-current signal, wherein, when the power assist unit receives the enable signal, the controller is configured to receive the current level indication, 1) to determine that a charge level on the power storage element is above a peak charge level threshold, to direct the converter to provide power from the power storage element to the power rail when the charge level is above the peak charge level threshold, and 2) to direct the converter to charge the power storage element at a maximum charge rate (CR) from the power rail when charge level is below the peak charge level threshold, and to provide a charge level indication that indicates an amount of charge on the power storage element, wherein the maximum charge rate (CR) is given as:
• CR=PAvailable−PBudget
• where (PAvailable) represents a maximum available power based upon the current level indication and PBudget represents a power budget for the information handling system;
• and
• a baseboard management controller configured to receive the charge level indication, and to set a peak power limit for power consumed by the load based on the charge level indication.