Drive System Torque Control via Clutch Capacity Limits
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Drive systems for motor vehicles face challenges in rapidly adjusting to varying driving situations while avoiding thermal or mechanical overloading, which can lead to premature component failure and reduced efficiency, particularly when the drive torque exceeds the maximum torque that can be transmitted by the clutches, causing slip and thermal loading.
Innovation Solution
A method for controlling the drive system that involves ascertaining the maximum torque that can be transmitted by each clutch, limiting the drive torque provided by the drive unit to match the sum of the maximum torques, and operating the drive unit to provide only the limited torque, thereby preventing excessive slip and thermal loading.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the drive torque is increased to rapidly adjust to varying driving situations, then the responsiveness and adaptability of the drive system is improved, but the clutches may experience thermal or mechanical overloading leading to premature failure
Solution Approach 1:
The control unit calculates the maximum transmissible torque through the clutch stages in advance (before actual torque transmission) and uses this pre-calculated information to limit the drive torque from the drive unit. This preliminary assessment of clutch capacity prevents overloading before it occurs, allowing the system to respond rapidly to driving situations while protecting clutch components from thermal or mechanical overloading that would compromise durability
Solution Approach 2:
The control unit continuously monitors the operating state of the drive system and dynamically adjusts the drive torque based on real-time feedback about clutch capacity. By constantly comparing the desired drive torque against the calculated maximum transmissible torque through the clutch stages, the system maintains optimal responsiveness while preventing clutch overloading, thus resolving the contradiction between adaptability and reliability
2Power
If the drive torque exceeds the maximum torque that can be transmitted by the clutches, then the drive unit can provide higher power output, but excessive slip and thermal loading occur causing energy loss and component damage
Solution Approach 1:
The control unit performs a preliminary calculation of the maximum torque that can be transmitted through each clutch stage and the cumulative capacity of multiple clutches before the drive unit delivers torque. This advance knowledge allows the control unit to limit the drive torque to match the clutch transmission capacity exactly, ensuring high power output is achieved without exceeding clutch capabilities and causing excessive slip, thermal loading, and associated energy losses
Solution Approach 2:
The control unit dynamically adjusts the drive torque parameter based on the calculated clutch transmission capacity. By changing the drive torque parameter to match the maximum transmissible torque through the clutch stages, the system optimizes power transmission efficiency, preventing the drive torque from exceeding clutch capacity and thereby avoiding excessive slip and thermal loading that would result in energy loss
3Adaptability or versatility
If multiple clutches are used to distribute torque to different output shafts, then the versatility and control flexibility of the drive system is improved, but the complexity of torque management and control increases
Solution Approach 1:
The control unit merges the torque management function for multiple clutches into a single integrated control architecture. By calculating the cumulative torque capacity of multiple clutch stages together and managing them as a unified system rather than separate independent clutches, the control unit simplifies torque management while maintaining the versatility to distribute torque flexibly to different output shafts according to driving requirements
Solution Approach 2:
The control unit is designed with multi-functionality to handle various torque distribution scenarios across multiple clutches and output shafts. This universal control approach can manage different clutch configurations and torque splitting strategies through a single integrated algorithm, reducing control complexity while maintaining high adaptability for diverse driving situations and torque distribution requirements
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 allows for precise and rapid adjustment of drive torque, reducing the risk of clutch damage, maintaining efficiency, and minimizing CO2 emissions by limiting the drive torque to the maximum that can be transmitted, thus preventing excessive slip and thermal loading.
Implementation Method 1
The two clutch elements can be, in particular, friction partners of a frictional connection
Implementation Method 2
an electrical machine (5) as drive unit (5)
Data Source
AI summary
A method controls a drive system for an axle of a motor vehicle, wherein the drive system has at least an electrical machine as drive unit, a drive shaft which is driven by the drive unit, a first output shaft and a second output shaft and also a first clutch which connects the drive shaft to the first output shaft and a second clutch which connects the drive shaft to the second output shaft.