DPF Soot Preloading After Regeneration for Stable PM Filtration

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Diesel particulate filters (DPFs) experience reduced particulate matter reduction efficiency after regeneration due to larger pore sizes allowing soot to pass through, failing to meet stringent particulate number (PN) regulations without structural changes or improvements.

Innovation Solution

A method involving regenerative, efficiency enhancement, and normal operation modes to manage soot deposition in DPFs, using parameters like engine rpm, torque, and air-fuel ratio to stabilize efficiency, with adjustments in EGR, common rail pressure, fuel injection timing, and throttle position.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the diesel particulate filter is regenerated to remove all accumulated soot, then the particulate matter removal capability is restored, but the pore size becomes relatively larger allowing soot to pass through easily, which lowers particulate matter reduction efficiency and may fail to meet regulatory standards

Engineering Contradiction:
Improveparticulate matter reduction efficiencyVSAvoidsoot passing through filter
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent applies preliminary action by intentionally depositing a controlled amount of soot back into the DPF after regeneration. This pre-deposition creates a barrier layer before normal operation resumes, preventing soot from passing through the enlarged pores while maintaining filtration efficiency. The soot is deposited in advance to prepare the filter for efficient particulate matter capture.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If the amount of particulate matter deposited in the diesel particulate filter increases, then the particulate matter reduction efficiency increases up to a certain extent, but when it accumulates to a limit and becomes clogged, regeneration is required which causes pore size enlargement

Engineering Contradiction:
Improveparticulate matter reduction efficiencyVSAvoidpore size structure
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent implements periodic action by cycling between regeneration phases (which enlarge pores) and controlled soot deposition phases (which restore filtration efficiency). This periodic alternation prevents the filter from remaining in a continuously degraded state with enlarged pores, instead rhythmically restoring its particulate matter capture capability through controlled soot accumulation followed by regeneration.

Inventive Principle:
Principle #19Periodic action

3Reliability

If structural changes or improvements are made to the diesel particulate filter to maintain efficiency after regeneration, then particulate matter reduction efficiency can be maintained, but device complexity and manufacturing cost increase

Engineering Contradiction:
Improveparticulate matter reduction efficiencyVSAvoidfilter structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies parameter changes by modifying the soot deposition parameter (amount and timing) rather than changing the physical structure of the DPF. By controlling the soot deposition quantity to a preset initial deposition amount after regeneration, the system maintains filtration efficiency through operational parameter adjustment instead of structural modification, thereby avoiding increased device complexity and manufacturing costs.

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

Stably maintains particulate matter reduction efficiency post-regeneration, meeting exhaust gas regulations without altering the DPF structure.

Implementation Method 1

diesel particulate filters (DPFs) are widely used to reduce particulate matter (PM) emitted from diesel engines

Methodology Applied
Scientific EffectPhysical filtration: Filter (physical)

Implementation Method 2

it goes through a regeneration process that removes the deposited particulate matter by burning it at high temperatures

Methodology Applied
Scientific EffectCombustion: Combustion

Implementation Method 3

the exhaust gas contains sufficient oxygen to internally burn the soot deposited in the diesel particulate filter (DPF)

Methodology Applied
Scientific EffectOxidation: Oxidation

Data Source

PatentEP4722509A1Method for removing particulate matter
Publication Date: 2026.04.08 HD HYUNDAI INFRACORE CO LTD
  • EP4722509A1 patent drawingFigure 1
  • EP4722509A1 patent drawingFigure 2
  • EP4722509A1 patent drawingFigure 3

AI summary

The present invention relates to a particulate matter reduction method for reducing particulate matter emitted from an internal combustion engine using a Diesel Particulate Filter (DPF), wherein the particulate matter reduction method according to an embodiment of the present invention comprises: a step of operating in a regenerative operation mode to combust and remove deposited particulate matter when particulate matter in the Diesel Particulate Filter exceeds a preset allowable deposition amount; a step of operating in an efficiency enhancement mode to forcibly increase a soot amount to deposit particulate matter up to a preset initial deposition amount in the Diesel Particulate Filter after the regenerative operation mode is terminated; and a step of stopping the forced increase of the soot amount and operating in a normal operation mode when the efficiency enhancement mode is terminated.