Engine Control Method for Diesel Particulate Filter Regeneration

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The frequent injection of diesel fuel into the combustion chamber to regenerate particulate filters in diesel engines leads to fuel dilution in the lubricating oil, causing increased viscosity reduction, lubricating properties degradation, and premature oil aging, necessitating shorter oil change intervals, which is undesirable.

Innovation Solution

A method to control the frequency of regeneration fuel injections based on calculating the foreseeable fuel concentration in the oil, adjusting the number of regenerations to maintain the fuel concentration below a predetermined threshold, thereby extending oil change intervals without degrading engine performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If frequent regeneration fuel injections are performed to meet emissions standards, then particulate filter regeneration is improved, but fuel dilution in lubricating oil increases

Engineering Contradiction:

Improveparticulate filter regenerationVSAvoidfuel dilution in lubricating oil

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The control system dynamically adjusts the regeneration strategy based on real-time monitoring of fuel dilution levels in the lubricating oil. When dilution exceeds a threshold, the system adapts by modifying injection parameters or timing to reduce further dilution while maintaining acceptable regeneration performance

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes operational parameters such as injection timing, injection quantity, or injection pressure to optimize the balance between regeneration effectiveness and fuel dilution control. By adjusting these parameters, the system can reduce fuel dilution while still achieving adequate particulate filter regeneration

Inventive Principle:

Principle #35Parameter changes

2Duration of action of stationary object

If fuel dilution in lubricating oil is reduced by decreasing regeneration frequency, then oil change intervals are extended, but emissions compliance may be compromised

Engineering Contradiction:

Improveoil change intervalVSAvoidemissions

Core Design Contradiction:

Duration of action of stationary objectVSObject-generated harmful factors

Solution Approach 1:

The control system continuously monitors fuel dilution levels in the lubricating oil and uses this feedback to adjust regeneration strategies. This closed-loop control ensures that emissions compliance is maintained while extending oil change intervals by optimizing the balance between regeneration frequency and dilution control

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

Instead of continuous or frequent regeneration injections, the system implements periodic regeneration cycles that are timed and dosed to achieve necessary filter regeneration while allowing sufficient intervals for fuel evaporation from the oil, thereby extending oil change intervals while maintaining emissions compliance

Inventive Principle:

Principle #19Periodic action

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 approach ensures the lubricating oil's properties remain intact, reducing the risk of mechanical failure and compliance with emissions standards by maintaining a lower fuel concentration in the oil, thus extending oil change intervals without requiring a degraded engine operating mode.

Implementation Method 1

The combustion of this diesel fuel within an oxidation catalyst upstream of the filter heats the exhaust gases and temporarily raises the filter temperature to 600°C

Methodology Applied

Scientific EffectCombustion: Combustion

Implementation Method 2

Because these injections occur after combustion, a significant portion of the injected fuel is deposited on the combustion chamber walls

Methodology Applied

Scientific EffectDeposition: Deposition (physical)

Implementation Method 3

the presence of fuel in the oil causes a drop in its viscosity and therefore its lubricating properties

Methodology Applied

Scientific EffectDilution:

Data Source

PatentEP2472088B1Engine control method which ensures an oil dilution which does not exceed a a maximum oil dilution at the next service

Publication Date: 2020.01.01 PSA AUTOMOBILES SA

Figure 1~2
Figure 3

AI summary

The method involves determining remaining distance to be traveled (100) till next lubricating oil change in an internal combustion engine. Concentration of fuel in the oil expectable at the next oil change is calculated (102) based on current frequency of regeneration fuel injections. A regeneration fuel injection frequency, for which the concentration of fuel expectable at the next oil change is less than a preset threshold (104), is calculated (106) if the calculated concentration exceeds the threshold. The regeneration fuel injections (108) are carried out with the calculated frequency.