Torque Gradient Decrement Calibration for Jerk-Free Deceleration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for filtering setpoint torque during deceleration in vehicles with thermal powertrains struggle to balance jerk prevention and fuel efficiency, as the steepness of torque slopes is not effectively controlled, leading to either jerky deceleration or overconsumption.
Innovation Solution
A method that calibrates the decrement of torque slopes independently of transition time to manage torque slopes directly, allowing for precise control of slope stiffness and reducing fuel consumption by parameterizing decrements based on gearbox ratio, engine speed, and deceleration torque.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a steep torque slope is applied to reach engine loss torque quickly, then deceleration response is improved, but fuel injection cutoff generates jolts reducing driving comfort
Solution Approach 1:
The patent applies a dynamic approach by adjusting the torque slope steepness based on real-time engine operating conditions. The control module modifies the preventive torque gradient according to engine speed, load, and temperature parameters, allowing the system to optimize deceleration behavior adaptively rather than using a fixed slope profile.
Solution Approach 2:
The patent changes key parameters including torque gradient limits, engine speed thresholds, and fuel injection cutoff criteria based on operating conditions. By dynamically adjusting these parameters, the system prevents jolts during fuel cutoff while maintaining responsive deceleration when conditions permit steeper torque changes.
2Object-affected harmful factors
If a flat torque slope is applied to prevent jolts during deceleration, then driving comfort is improved, but deceleration becomes slow increasing fuel consumption
Solution Approach 1:
The system dynamically adjusts torque slope steepness based on real-time engine conditions such as speed, load, and temperature. This allows the control module to apply steeper slopes when engine conditions permit (reducing fuel consumption) while maintaining comfort when conditions require gentler transitions.
Solution Approach 2:
The patent modifies operating parameters including torque gradient limits and fuel injection timing based on engine state. By changing these parameters dynamically, the system optimizes the balance between deceleration speed and comfort, preventing excessive fuel consumption while avoiding jolts.
3Device complexity
If transition time is fixed for torque slope application, then control simplicity is maintained, but torque slope steepness cannot be optimized for varying engine loss torque levels
Solution Approach 1:
The patent implements dynamic adjustment of torque slope characteristics based on real-time engine operating conditions. The control module continuously monitors engine parameters and modifies the preventive torque gradient accordingly, enabling optimization of torque transitions without requiring complex fixed-time control logic.
4Use of energy by moving object
If fuel injection is cut off during deceleration to improve fuel efficiency, then energy consumption is reduced, but sudden torque changes create jolts affecting driving pleasure
Solution Approach 1:
The patent applies preliminary action by gradually reducing the torque slope steepness as the engine approaches fuel cutoff conditions. The control module prepares the torque transition in advance, smoothing the gradient before fuel injection is completely cut off, thereby preventing jolts while still achieving fuel efficiency benefits.
Solution Approach 2:
The system dynamically changes torque gradient parameters and fuel injection timing based on engine operating state. By adjusting these parameters in real-time, the system optimizes the balance between fuel efficiency and driving comfort, enabling fuel cutoff when appropriate while preventing jolts through controlled torque transitions.
Data Source
Figure 1~2
Figure 3~4
AI summary
The invention relates mainly to a method for filtering a reference torque (Cc) to an engine loss torque (Cpm1, Cpm2) to be reached during a deceleration of a vehicle provided with a thermal power train, comprising: a step of determining the reference torque (Cc); and a preventive filtering step comprising a step of applying at least one torque gradient (P3, P3') to a preventive torque (Cp) in order gradually to reach said engine loss torque (Cpm1, Cpm2), characterised in that a decrease of said torque gradient (P3, P3') is calibrated independently from a transition time (t30, t30') between the start and the end of applying said calibrated torque gradient (P3, P3') in order to reach said engine loss torque (Cpm1, Cpm2).