Engine Sensor Drift Compensation via Joint Evaluation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for operating internal combustion engines face challenges in accurately determining engine performance quantities for combustion control due to the lower accuracy and greater tolerances of structure-borne noise sensors compared to pressure sensors.
Innovation Solution
A method that involves joint evaluation of signals from pressure sensors and structure-borne noise sensors, allowing for drift compensation and precise engine control by establishing reference characteristic curves and phase shifting, enabling accurate determination of performance quantities like start of combustion and maximum pressure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If structure-borne noise sensors are used for combustion control, then cost and installation simplicity are improved, but measurement precision deteriorates due to lower accuracy and greater tolerances
Solution Approach 1:
The patent divides the measurement system into two segments: a first sensor (pressure sensor) that provides high-precision reference measurements and a second sensor (structure-borne noise sensor) that provides continuous monitoring data. By segmenting the measurement functions and using the first sensor to calibrate and correct the second sensor, the system achieves both cost-effectiveness and high measurement precision for combustion control quantities.
2Device complexity
If structure-borne noise sensors are used for combustion control, then device complexity is reduced, but reliability deteriorates due to sensor drift over time
Solution Approach 1:
The patent implements a feedback mechanism where the first sensor continuously monitors the combustion chamber pressure and provides reference values for combustion control quantities. These reference values are used to detect drift in the second sensor and to continuously correct its measurements, ensuring long-term reliability and stability of the combustion control system despite the use of simpler structure-borne noise sensors.
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 method ensures reliable and precise engine operation by compensating for sensor drift, achieving similar accuracy to pressure sensors and maintaining performance across varying operating conditions and sensor ages.
Implementation Method 1
a pressure sensor which detects the pressure in a cylinder (guide cylinder) of the engine
Implementation Method 2
the engine has a structure-borne noise sensor, which indirectly detects the pressure changes in the individual cylinders
Data Source
AI summary
In a method for operating an internal combustion engine, a first data quantity is derived based on a signal of a first sensor which detects the pressure in a first combustion chamber of a plurality of combustion chambers, and a second data quantity is derived based on a signal of a second sensor, which second data quantity is a function of the pressure variation in at least one of the plurality of combustion chambers. The first data quantity and the second data quantity are functions of the pressure variation in the same combustion chamber, and a drift of the second sensor is ascertained from a change over time in the second data quantity with respect to the first data quantity.