Engine Air Metering Control for Rapid Restart Prediction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining the coasting duration of an internal combustion engine are complex and not robust, especially in 'change-of-mind' situations where rapid restart is desired, as they do not accurately predict the engagement point for the starter based on coasting speed.
Innovation Solution
The method involves determining the coasting speed at a defined point, such as during a top dead center, and adjusting the air metering device's opening degree as a function of this speed to establish a linearly decreasing relationship between coasting speed and duration, allowing for precise prediction of the starter engagement point.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the air metering device is opened equally far independently of the coasting speed, then the duration of the coasting procedure can be determined in principle, but the method becomes complex and not robust
Solution Approach 1:
The patent applies parameter changes by establishing a functional relationship between the degree of opening of the air metering device and the coasting speed. Instead of using a fixed opening degree, the control unit adjusts the opening degree as a variable parameter that changes with the measured coasting speed, thereby simplifying the control logic while maintaining prediction accuracy
Solution Approach 2:
The patent implements preliminary action by determining the coasting speed early in the coasting phase and using this information to predict the engagement point in advance. The control unit calculates the appropriate air metering device opening degree before the engagement event occurs, allowing for proactive control rather than reactive adjustment
2Ease of operation
If the coasting speed is ascertained at a defined point in time and the degree of opening is selected as a function of coasting speed, then the engagement point can be determined in a simple way, but requires precise speed measurement
Solution Approach 1:
The patent implements feedback by continuously measuring the coasting speed of the internal combustion engine and using this measured value to adjust the degree of opening of the air metering device. The control unit receives speed feedback from the engine and dynamically adjusts the air supply based on the actual coasting behavior, creating a closed-loop control system
3Productivity
If a linearly decreasing relationship is established between coasting speed and duration, then rapid restart is enabled, but requires sophisticated control logic
Solution Approach 1:
The patent applies dynamics by making the degree of opening of the air metering device dynamically adjustable based on the current coasting speed. The system transitions from static, fixed opening degrees to dynamic, speed-dependent opening degrees, allowing the control characteristics to adapt in real-time to the engine's coasting state and achieve optimal restart performance
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 enables a simple, robust, and rapid restart of the internal combustion engine by determining the engagement point in advance, particularly in 'change-of-mind' situations, by linking the coasting speed to the kinetic rotational energy and using a polynomial or square of the coasting speed for precise calculations.
Implementation Method 1
a decelerating torque results in sum due to the compression of the air spring in the intake cylinder when the intake cylinder enters a compression stroke
Data Source
AI summary
A method for stopping an internal combustion engine, in which an air flow supplied via an air metering device, in particular a throttle valve of the internal combustion engine, is reduced after a stopping request has been ascertained, an undershoot point in time is ascertained, at which an ascertained speed of the internal combustion engine falls below a pre-definable speed threshold value, after the undershoot point in time, the air flow supplied via the air metering device of the internal combustion engine is increased again, the predefinable speed threshold value being selected in such a way that an intake cylinder no longer enters a compression stroke after the increase of the supplied air flow until the internal combustion engine is at a standstill, a degree of opening of the air metering device to increase the supplied air flow being selected as a function of a coasting speed of the internal combustion engine.