Attenuating Curative Torque to Prevent Engine Stalling

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Solution Overview

Problem

The simultaneous activation of idle speed and curative comfort regulators in vehicles can lead to stalling and disturbance of engine speed oscillations, compromising driving pleasure and comfort, as existing solutions either prioritize one regulator over the other or modify parameters, which do not adequately address the issue of maintaining comfort without stalling.

Innovation Solution

A torque control method that attenuates the corrective torque produced by the curative comfort regulator when both regulators are activated, using a weighting coefficient to reduce speed oscillations without canceling the corrective torque unless there is a risk of engine stalling, and deactivates the curative regulator if the engine speed deviation exceeds a threshold, ensuring the idle speed regulator's priority.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the curative comfort regulator is activated to compensate for engine speed oscillations, then driving pleasure is improved, but the risk of engine stalling increases when simultaneously activated with the idle speed regulator

Engineering Contradiction:
Improvedriving pleasureVSAvoidengine stalling risk
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent applies dynamics by making the curative comfort regulator's gain factor variable rather than fixed. The gain factor is dynamically adjusted based on the engine operating point, specifically reducing it when the engine is in a vulnerable state (low speed, high load) where stalling risk is present. This allows the regulator to provide comfort when safe and reduce its action when stalling risk exists.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the parameter of the curative comfort regulator's gain factor based on engine operating conditions. By monitoring engine speed and load, the system modifies the regulator's responsiveness parameter in real-time, reducing the corrective torque when the engine is vulnerable to stalling while maintaining it when the engine is in a stable state.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If the idle speed regulator prioritizes maintaining engine speed setpoint, then engine stalling is avoided, but engine speed oscillations remain perceptible to occupants

Engineering Contradiction:
Improveengine stalling avoidanceVSAvoiddriving pleasure
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The patent merges the actions of the idle speed regulator and curative comfort regulator by making them work simultaneously with coordinated gain factors. Instead of excluding one regulator when the other is active, the system combines both regulators' corrective actions, with the curative regulator's gain factor adjusted to complement rather than conflict with the idle speed regulator's maintaining action.

Inventive Principle:
Principle #5Merging (Combining)

3Adaptability or versatility

If both regulators are activated simultaneously to address different engine speed issues, then comprehensive speed control is achieved, but the regulators disturb each other and self-feed speed oscillations

Engineering Contradiction:
Improvespeed control coverageVSAvoidengine speed stability
Core Design Contradiction:
Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The patent changes the parameter of the curative comfort regulator's gain factor based on the engine operating point. When the engine is in a vulnerable state (low speed, high load), the gain factor is reduced to prevent the regulator from over-correcting and creating instability. This parameter adaptation allows both regulators to work together without self-feeding oscillations.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The system uses feedback from engine speed and load sensors to continuously monitor the engine state and adjust the curative comfort regulator's gain factor accordingly. This feedback mechanism prevents the regulators from interacting in harmful ways by detecting when the engine is vulnerable to stalling and reducing the corrective action accordingly.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP3066325B1Method for reducing the torque of the corrective oscillation-reducing function in case of the activation of an idle-speed regulator and corresponding engine computer
Publication Date: 2018.01.03 PSA AUTOMOBILES SA
  • EP3066325B1 patent drawingFigure 1~2

AI summary

The invention mainly relates to a method for controlling the torque of a heat engine provided with a first governor (4), referred to as idling speed control valve, capable of generating an idling torque (Cral) intended for maintaining a predetermined set idling speed (Wral) such as to prevent said heat engine from stalling, and a second governor (6), referred to as a curative smoothing governor, capable of compensating for an oscillation in the speed of the heat engine (Wm) by applying a corrective torque in phase opposition with the speed of the heat engine (Wm), characterised in that in the event of simultaneous activation of the idling speed control valve (4) and the curative smoothing governor (6), said method comprises the step of attenuating said corrective torque produced by said curative smoothing governor (6) without cancelling same unless there is a risk of the heat engine stalling. The invention also relates to the corresponding engine computer.