Segmented Power Terminals for Hot-Swap Inrush Current Limiting

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional electrical devices with high power and high power density experience sparking and ablation during hot swap due to large transient impulse currents when connected to power sourcing equipment with high output voltage, affecting electrical connections and user experience.

Innovation Solution

The electrical device is designed with power terminals partitioned into two conductive sections connected in series by a resistor, and capacitors are placed between these terminals to limit current, ensuring stable voltage and reduced impulse currents during hot swap.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional edge connector with two connection terminals is used for hot swap connection, then electrical connection can be established, but sparking and ablation occur due to large transient impulse currents

Engineering Contradiction:
Improveelectrical connection stabilityVSAvoidsparking and ablation
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The power terminal is segmented into two conductive sections (first and second conductive sections) spaced along the insertion direction. This segmentation allows sequential contact during insertion, where the first conductive section contacts first to perform current-limiting charging through the resistor, and the second conductive section contacts later to complete the power connection, thereby reducing transient impulse currents and preventing sparking and ablation

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A resistor is introduced as an intermediary element connected in series between the two conductive sections. This resistor acts as a current-limiting device that controls the charging current of the capacitor during the hot swap process, preventing large transient impulse currents from directly flowing through the power terminal and causing harmful sparking and ablation effects

Inventive Principle:
Principle #24Intermediary (Mediator)

2Power

If high power and high power density are used in electrical device, then power output capability is improved, but transient impulse currents increase causing sparking and ablation

Engineering Contradiction:
Improvepower output capabilityVSAvoidtransient impulse currents
Core Design Contradiction:
PowerVSObject-affected harmful factors

Solution Approach 1:

A capacitor is connected in parallel with the power terminal to perform preliminary energy storage. During the hot swap insertion process, the capacitor is charged through the current-limiting resistor before the full power connection is established. This preliminary action prepares the electrical device for high power operation while controlling the transient impulse currents that would otherwise cause sparking and ablation

Inventive Principle:
Principle #10Preliminary action

3Ease of operation

If connection terminals are spaced at interval for separate electrical contact, then hot swap connection is enabled, but large voltage difference causes impulse currents during connection

Engineering Contradiction:
Improvehot swap capabilityVSAvoidelectrical connection stability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The power terminal is divided into two spaced conductive sections that make separate contact during hot swap insertion. This segmentation enables hot swap capability while the resistor-capacitor circuit manages the voltage difference between sections, preventing impulse currents and maintaining electrical connection stability

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The resistor and capacitor parameters are specifically designed to control the charging process. The resistor limits the charging current rate, and the capacitor stores energy to smooth voltage transitions. By carefully selecting these parameter values, the system achieves both hot swap capability and electrical connection stability without impulse currents

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This design reduces the risk of sparking and ablation, improves contact impedance stability, and protects components by minimizing impulse currents, enhancing user experience and electrical connection stability.

Implementation Method 1

the first conductive section, the resistor, and the second conductive section are connected in series

Methodology Applied
Scientific EffectElectrical Resistance: Electrical Resistance

Implementation Method 2

capacitors are disposed between power circuits that are electrically connected to two power terminals

Methodology Applied
Scientific EffectCapacitance: Capacitance

Data Source

PatentEP4383957B1Electrical device
Publication Date: 2026.02.04 HUAWEI DIGITAL POWER TECH CO LTD
  • EP4383957B1 patent drawingFigure 1
  • EP4383957B1 patent drawingFigure 2
  • EP4383957B1 patent drawingFigure 3

AI summary

Embodiments of this application provide an electrical device, including a substrate and two power terminals that are disposed at an interval on the substrate. At least one of the power terminals is partitioned into two conductive sections that are spaced along an insertion direction of the substrate and are connected in series by using a resistor; and capacitors are disposed between power circuits that are electrically connected to the two power terminals. When hot swap is performed between the electrical device and a piece of power sourcing equipment, current-limiting charging is first performed on the capacitors by using a conductive section located in the front of the insertion direction of the substrate; and then a conductive section located at the rear of the insertion direction of the substrate is connected to implement power input. In this way, even if an output voltage of the power sourcing equipment is high, phenomena such as sparking and ablation are not likely to occur at the two power terminals, and electrical connections between the electrical device and the power sourcing equipment are not easily affected.