Dual Electric LSD Torque Control for Uneven Wheel Traction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing differential systems in vehicles fail to effectively distribute power to both main and auxiliary driving wheels when their tractions differ, limiting overall driving force and causing wheel slip during turns.
Innovation Solution
Implementing electric limited slip differentials on both main and auxiliary driveshafts, controlled by a controller that adjusts torque limits based on axial load and road friction coefficients to synchronize wheel speeds and optimize power distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an LSD is mounted only on the main driving wheel, then wheel spin of the main driving wheel is inhibited, but the total driving force of the vehicle cannot be sufficiently utilized
Solution Approach 1:
The patent divides the single LSD function into two separate LSD units, one mounted on the main driving wheel and another on the auxiliary driving wheel. This segmentation allows each driveshaft to independently control wheel spin, thereby inhibiting wheel spin on both main and auxiliary driving wheels while maximizing the utilization of total driving force.
2Ease of operation
If a differential apparatus distributes power to driving wheels with different traction, then power is transferred to the wheel with smaller traction, but insufficient power is transferred to the wheel with larger traction
Solution Approach 1:
The patent applies different torque limit values to the first and second LSDs based on local conditions (axial loads on respective driveshafts). The controller determines torque limit values according to the axial load of each driveshaft, allowing each LSD to operate with optimized local parameters. This ensures that power is effectively distributed to wheels with larger traction while maintaining smooth operation under varying traction conditions.
Data Source
AI summary
In a vehicle and a method of controlling the same, the vehicle may include: a first electric limited slip differential provided on a first driveshaft, and limiting differential actions of a left wheel and a right wheel of the first driveshaft; a second electric limited slip differential provided on a second driveshaft, and limiting differential actions of a left wheel and a right wheel of the second driveshaft; and a controller operatively connected to the first and second electric limited slip differentials and configured for controlling a torque limit value of the first electric limited slip differential and a torque limit value of the second electric limited slip differential based on a difference between an axial load of the first driveshaft and an axial load of the second driveshaft.