Decoupling Observer Algorithm for Cross-Sensitive Exhaust Gas Sensors
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Solution Overview
Problem
Current sensor technologies for measuring NOx and NH3 in diesel exhaust are cross-sensitive, making it difficult to control SCR devices efficiently, and existing solutions are expensive and unsuitable for automotive applications.
Innovation Solution
A method and system that combines signals from sensors with dissimilar sensitivities and applies a decoupling observer algorithm to simultaneously measure NOx and NH3 concentrations, enabling the use of less expensive sensor technologies and improving control module and intelligent sensor configurations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If two identical sensors are used to measure NOx and NH3 by splitting the exhaust path, then measurement precision is improved, but device complexity and cost increase significantly
Solution Approach 1:
The patent combines two sensors with different sensitivities into a single measurement system, merging their outputs through signal processing to achieve simultaneous measurement of both NOx and NH3 without requiring separate physical measurement paths
Solution Approach 2:
The patent introduces a decoupling observer algorithm as an intermediary computational layer that processes the combined sensor signals, separating the cross-sensitive measurements to extract accurate individual concentrations of NOx and NH3
2Productivity
If sensors with high speed response are used for immediate control, then productivity is improved, but cross-sensitivity to each other increases
Solution Approach 1:
The decoupling observer algorithm continuously processes sensor outputs with feedback mechanisms, using the known sensitivity characteristics of each sensor to mathematically separate their cross-sensitive responses and provide accurate individual component measurements for immediate control
Solution Approach 2:
The patent changes the approach from physical separation to mathematical separation by transforming the sensor signal parameters through the decoupling observer algorithm, converting cross-sensitive measurements into accurate individual component concentrations
Data Source
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AI summary
A method for simultaneously measuring one or more properties (e.g. temperature, concentration of NOx and ammonia, etc) in an exhaust gas mixture. Signals from one or more sensors that are cross-sensitive to one or more gases can be combined. A decoupling observer algorithm can be applied, such that these cross-sensitivities are decoupled. The sensors simultaneously obtain an estimate of one or more gases in the diesel exhaust. .A decoupling observer algorithm can be structured and arranged to be operable among a plurality of positions corresponding to several internal configurations.