Engine Control Surplus Richness for Overheating Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Internal combustion engines face a risk of temporary overheating when transitioning between operating points due to the latency in coolant temperature adjustment, leading to potential exceedance of admissible temperature thresholds and increased fuel consumption.
Innovation Solution
A method that dynamically controls coolant temperature and fuel injection by determining a surplus richness to be added to the fuel mixture, progressively reducing it based on burnt gas temperature, and adjusting coolant temperature setpoints to manage engine block temperature within safe limits, using a proportional, integral, and derivative regulator.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the coolant temperature setpoint is reduced when transitioning to high load operating points, then the engine block temperature can be controlled within admissible limits, but the coolant temperature cannot vary instantaneously due to thermal inertia, causing temporary overheating
Solution Approach 1:
The system performs preliminary action by detecting the operating point transition and proactively adjusting the fuel injection quantity before the coolant temperature can respond. The control unit calculates a temperature increase based on the difference between current and target operating points, and adjusts the fuel quantity accordingly in advance to prevent overheating during the coolant's thermal response latency.
2Temperature
If the fuel injection quantity is increased to prevent overheating during operating point transitions, then the engine block temperature rise is limited, but fuel consumption increases
Solution Approach 1:
The system applies dynamics by continuously monitoring the actual operating point and dynamically adjusting the fuel injection quantity based on real-time conditions. The control unit calculates the temperature increase and adjusts the fuel quantity proportionally to the operating point transition magnitude, allowing the system to adapt fuel consumption to the actual cooling demand rather than using a fixed conservative approach.
Solution Approach 2:
The system implements feedback by continuously measuring the actual operating point and comparing it with the target operating point. Based on this feedback, the control unit calculates the temperature increase and adjusts the fuel injection quantity accordingly. This closed-loop control ensures that fuel consumption is optimized by only adding excess fuel when and where needed to prevent overheating.
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 limits engine block temperature rise and reduces fuel consumption by rapidly blocking temperature increases and gradually reducing excess fuel injection as coolant temperature stabilizes, ensuring safe operating conditions while minimizing fuel usage.
Implementation Method 1
the temperature of the coolant and the quantity of fuel injected into the cylinders of the engine block so as to limit the variations in temperature of this engine block
Implementation Method 2
the quantity of fuel injected into the cylinders of the engine block
Data Source
Figure 1
Figure 2
AI summary
The invention relates to the control of an internal combustion engine (1), in which, - the value of a characteristic parameter is acquired at a first operating point (R; C), and from that a first setpoint temperature for the liquid coolant (CTl1) and a first setpoint for the richness (Cr1) of the air/fuel mixture to be admitted to the engine are deduced. If, on passing to a second operating point, a second setpoint temperature is below the first setpoint temperature, provision is made to carry out the steps: a) of determining an additional richness (Ar) to be added to a second richness setpoint, b) of acquiring the burnt-gases temperature (Tgb), and c) of progressively reducing the richness surplus as a function of the acquired burnt-gases temperature.