Electric Motor Braking Torque Control for Wheel Sliding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electric drive vehicles with independent wheel motors lack effective traction control during retarding, as they do not have a direct mechanical linkage between drive wheels, making them susceptible to wheel sliding due to differential traction conditions.
Innovation Solution
A traction control system that includes an electric motor associated with each wheel and a controller to determine the rotational speed of the wheel, compare it to an allowable slide threshold, and adjust the braking torque to prevent wheel sliding during retarding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If electric motors are used to independently drive each wheel, then the vehicle achieves better traction control and maneuverability, but the vehicle becomes susceptible to wheel sliding during retarding due to lack of mechanical linkage between wheels
Solution Approach 1:
The patent replaces the traditional mechanical differential linkage system with an electronic control system. The controller monitors wheel speeds and independently adjusts braking torque for each wheel via electronic signals to the electric motors, eliminating the need for mechanical connections between wheels while maintaining traction control during retarding operations
Solution Approach 2:
The system implements a feedback control mechanism where the controller continuously monitors the rotational speed of each wheel and adjusts the braking torque accordingly. When wheel sliding is detected during retarding, the controller modulates the electric motor braking torque to prevent excessive speed differential between wheels, ensuring stable traction control
2Power
If electric retarding is applied to rear wheels, then braking efficiency is improved, but wheel sliding is increased due to higher ground friction requirements
Solution Approach 1:
The patent applies different braking torques to different wheels based on their individual traction conditions. The controller independently controls the electric motor braking torque for each wheel, allowing optimal braking force distribution that prevents wheel sliding while maintaining high braking efficiency during retarding operations
Solution Approach 2:
The system dynamically adjusts the braking torque applied by each electric motor based on real-time wheel speed feedback. During retarding, the controller continuously modulates the braking force to maintain optimal traction conditions, preventing wheel slide while maximizing braking power utilization
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
The system effectively maintains wheel traction by adjusting braking torque, preventing wheel sliding and ensuring stable operation during retarding, even in conditions of differential traction.
Implementation Method 1
an electric motor associated with at least one wheel and adapted to provide braking torque to the wheel
Implementation Method 2
a controller configured to determine a rotational speed of the at least one wheel
Implementation Method 3
adjust the braking torque to the at least one wheel during retarding if the speed is less than the allowable slide threshold
Data Source
AI summary
A traction control system for a machine having an electric drive configuration is disclosed. The traction control system includes an electric motor associated with at least one wheel and adapted to provide braking torque to the wheel. The control system further includes a controller configured to determine a rotational speed of the at least one wheel, compare the rotational speed to an allowable slide threshold, and adjust the braking torque to the at least one wheel during retarding if the speed is less than the allowable slide threshold.