Power Supply Idle Control Line Efficiency

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Solution Overview

Problem

Traditional desktop power supplies are inefficient at low loads, resulting in significant energy losses, as their efficiency decreases with decreasing load, leading to substantial waste in power and heat generation.

Innovation Solution

A system that includes a power supply unit (PSU) and a computing device with an interface featuring an idle control line, allowing the computing device to indicate its idle state to the PSU, which then reduces consumption and increases efficiency by turning off fans, power supply phases, or providing power on select power rails.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If traditional desktop power supplies operate at low loads, then they can support modern computing devices trending towards low power states, but their efficiency decreases significantly leading to energy losses of 50% to 60%

Engineering Contradiction:

Improveability to support low power operating statesVSAvoidenergy losses

Core Design Contradiction:

Adaptability or versatilityVSLoss of energy

Solution Approach 1:

The power supply unit dynamically adjusts its operational characteristics based on load conditions. The control circuit monitors the load level and switches between different operational modes: at full load it operates in conventional mode, while at low load it transitions to a power-saving mode where it stops switching the primary side switch and regulates output voltage through pulse-frequency modulation on the secondary side, thereby maintaining efficiency across varying load conditions

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes key operational parameters based on load conditions. At low load, the control circuit alters the switching frequency and duty cycle of the primary side switch, transitions from continuous to discontinuous conduction mode, and adjusts the regulation method from primary-side voltage regulation to secondary-side current regulation, optimizing efficiency for low-power operation

Inventive Principle:

Principle #35Parameter changes

2Reliability

If power supply operates continuously to maintain readiness, then it can respond immediately to load demands, but it generates significant heat and consumes excess power during idle states

Engineering Contradiction:

Improvereadiness to respond to loadVSAvoidheat generation

Core Design Contradiction:

ReliabilityVSTemperature

Solution Approach 1:

The power supply employs periodic switching action only when necessary. During low-load conditions, instead of continuous switching, the system uses periodic pulse-frequency modulation on the secondary side to maintain output voltage while allowing the primary side to remain in a low-power state, reducing heat generation while maintaining readiness

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The control circuit extracts and removes the excessive power consumption and heat-generating components from the system during idle states. By detecting low load conditions, it disables the primary side switching and associated high-power components, keeping only the essential secondary side regulation active, thereby reducing heat generation while maintaining basic functionality

Inventive Principle:

Principle #2Taking out (Extraction)

Data Source

PatentUS10481661B2Power supply interface light load signal

Publication Date: 2019.11.19 INTEL CORP

AI summary

A system to provide an indication to a power supply unit that a computing device operably coupled to the power supply unit is idle. The system includes an interface including power rails to provide power from the power supply unit to the computing device and an idle control line to provide an indication from the computing device to the power supply unit that the computing device is idle.