NSR Catalyst Control Apparatus for Dynamic Rich Spike Processing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing technologies for internal combustion engines with NOx storage reduction catalysts (NSR) often perform unnecessary rich spike processing, leading to increased fuel consumption and NOx discharge, even when there is still storage capacity available in the NSR catalyst.
Innovation Solution
A control apparatus that determines whether to perform rich spike processing based on the NOx storage capacity and temperature of the NSR catalyst, only executing the process when storage ability is exhausted, and avoiding it when there is still margin, thereby optimizing fuel efficiency and reducing NOx discharge.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If rich spike processing is performed when transitioning from lean to stoichiometric air fuel ratio, then NOx discharge from NSR catalyst is suppressed, but fuel consumption increases due to unnecessary processing
Solution Approach 1:
The invention changes the control parameter from a fixed threshold-based approach to a dynamic approach that considers both NOx storage amount and temperature. By adjusting the determination criteria based on temperature conditions, the system performs rich spike processing only when necessary, avoiding unnecessary fuel consumption while maintaining effective NOx discharge suppression.
Solution Approach 2:
The invention implements feedback control by continuously monitoring both the NOx storage amount and temperature of the NSR catalyst. The control unit uses this real-time information to dynamically determine whether to execute rich spike processing, ensuring that processing is performed only when the actual conditions indicate necessity, thereby optimizing the balance between NOx control and fuel efficiency.
2Reliability
If rich spike processing is performed based on fixed threshold values, then NOx storage capacity is maintained, but processing is executed unnecessarily when storage ability remains
Solution Approach 1:
The invention transitions from a static threshold-based control system to a dynamic control system that adapts to changing temperature conditions. By making the determination criteria dynamic and temperature-dependent, the system maintains reliable NOx storage capacity management while avoiding unnecessary rich spike processing that would reduce fuel efficiency.
3Use of energy by moving object
If rich spike processing is avoided to reduce fuel consumption, then NOx may be discharged from NSR catalyst when storage ability is exhausted
Solution Approach 1:
The control unit continuously monitors both NOx storage amount and temperature, using this feedback to make informed decisions about when rich spike processing is necessary. This ensures that processing is not avoided prematurely, preventing NOx discharge while minimizing unnecessary fuel consumption.
Solution Approach 2:
The invention adjusts the control parameters based on temperature conditions, lowering the threshold for initiating rich spike processing at higher temperatures where NOx discharge risk is greater. This dynamic parameter adjustment ensures adequate NOx control while avoiding excessive processing at temperatures where it would be unnecessary.
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 effectively suppresses NOx discharge from the NSR catalyst while minimizing unnecessary fuel consumption by aligning rich spike processing with the actual NOx storage capacity and temperature conditions, enhancing engine efficiency and emission control.
Implementation Method 1
a catalyst container comprising means absorbing nitrogen oxides contained in said gases
Implementation Method 2
the air fuel ratio of exhaust gas flowing into the NSR catalyst is controlled from the stoichiometric air fuel ratio to a rich air fuel ratio (rich spike processing), so that the NO X stored in the NSR catalyst is reduced and purified (removed)
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A control apparatus for an internal combustion engine having an exhaust gas purification device which is arranged in an exhaust passage and includes a NOx storage reduction (NSR) catalyst. The control apparatus, when the air fuel ratio of the air-fuel mixture is shifted from a lean air fuel ratio to the stoichiometric air fuel ratio, determines a predetermined NOx amount so as to be larger when the temperature detected by the first detection unit is high in comparison with when the detected temperature is low, and when the storage amount of NOx in the NSR catalyst is larger than the predetermined NOx amount, performs the rich spike processing and then controls the air fuel ratio to the stoichiometric air fuel ratio, whereas when otherwise, controls the air fuel ratio to the stoichiometric air fuel ratio without performing the rich spike processing.