DPF PM Accumulation Evaluation with Sensor Failure Redetermination

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing exhaust gas purification systems for engines with diesel particulate filters (DPF) face challenges in accurately estimating PM accumulation states and scheduling regeneration treatments due to sensor failures, leading to potential engine output reduction, DPF damage, or increased fuel consumption.

Innovation Solution

An exhaust gas purification system that includes a PM accumulation evaluation part with a current stage determination, evaluation stage determination, defect detection, and redetermination mechanisms, allowing for continuous evaluation and adjustment of PM accumulation stages even when sensors fail, using alternative indices and units to maintain accurate PM accumulation state estimation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If multiple sensors are used to calculate evaluation indices for PM accumulation state, then measurement precision is improved, but reliability deteriorates due to sensor failures

Engineering Contradiction:
ImprovePM accumulation state estimation accuracyVSAvoidsystem reliability under sensor failure
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The system dynamically changes the parameters used for evaluation based on sensor status. When a sensor fails, the system switches from using multiple evaluation indices (including sensor-based ones) to using only non-sensor-based indices or alternative sensor data, thereby maintaining reliability while adapting to the degraded state

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The system prepares alternative evaluation methods in advance for when sensor failures occur. By pre-establishing backup evaluation indices that do not depend on faulty sensors, the system cushions against the impact of sensor failures and maintains continuous reliable operation

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

2Reliability

If regeneration treatment is performed frequently to prevent DPF damage and maintain engine output, then reliability is improved, but fuel consumption increases

Engineering Contradiction:
ImproveDPF performance maintenanceVSAvoidfuel consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The system continuously monitors multiple evaluation indices (PM accumulation amount, cumulative operation time, cumulative fuel consumption, DPF pressure difference) and uses this feedback to dynamically adjust regeneration timing. This feedback mechanism ensures regeneration is performed only when necessary, preventing both premature and delayed regeneration

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The regeneration control strategy is dynamic rather than static. The system adapts regeneration timing based on real-time conditions and the combined evaluation of multiple indices, allowing optimal balance between maintaining DPF performance and minimizing fuel consumption under varying operating conditions

Inventive Principle:
Principle #15Dynamics

3Use of energy by moving object

If regeneration treatment is delayed to reduce fuel consumption, then energy use is reduced, but engine output decreases and DPF may be damaged

Engineering Contradiction:
Improvefuel consumption reductionVSAvoidengine output and DPF integrity
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The continuous monitoring of multiple evaluation indices provides real-time feedback on PM accumulation state, enabling the system to identify the optimal regeneration timing that balances fuel consumption with maintaining engine output and DPF integrity

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system performs regeneration treatment preliminarily determined based on the evaluated PM accumulation state before critical thresholds are reached, preventing engine output reduction and DPF damage while avoiding excessive early regeneration

Inventive Principle:
Principle #10Preliminary 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

Enables accurate PM accumulation state estimation and timely regeneration treatments, even with sensor failures, thereby preventing engine output reduction, DPF damage, and fuel consumption issues.

Implementation Method 1

DPF is a device for collecting PM employing a filter

Methodology Applied
Scientific EffectFiltration: Filter (physical)

Implementation Method 2

a regeneration treatment for the filter where PM accumulated in the filter is combusted

Methodology Applied
Scientific EffectCombustion: Combustion

Data Source

PatentEP2806124B1Engine exhaust purification system
Publication Date: 2018.01.03 MITSUBISHI HEAVY IND LTD
  • EP2806124B1 patent drawingFigure 1~2
  • EP2806124B1 patent drawingFigure 3
  • EP2806124B1 patent drawingFigure 4

AI summary

An exhaust gas purification system of engine 2 configured to classify a PM accumulation state of DPF 34 into multiple evaluation stages based on a plurality of evaluation indices, and to repeatedly perform determination of the current evaluation stage by the current stage determination part 52a and determination of whether to move up the current evaluation stage to the evaluation stage of the next rank by the evaluation stage determination part 52b, wherein upon a defect of a sensor among different types of sensors being detected by the defect detection part, the current evaluation stage is newly redetermined by the current stage redetermination part 52c as substituted for the current evaluation stage determined by the current stage determination part 52a.