Electric AWD Torque Split Layout for Lower EV Energy Use
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing all-wheel drive systems in electric vehicles require additional torque from the electric motor, which decreases the vehicle's range or necessitates larger batteries, leading to inefficiencies.
Innovation Solution
An all-wheel drive system with a longitudinal axis configuration, utilizing a transverse-mounted electric motor and a planetary gear set to transfer torque efficiently to both front and rear wheels, incorporating clutches and differential systems to enable both all-wheel and two-wheel drive modes, optimizing torque distribution and reducing the need for additional motor power.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If traditional gear arrangements are used to transfer torque from the electric motor to the wheels, then the drive system can transmit torque to the wheels, but additional torque from the electric motor is required which decreases vehicle range or necessitates larger batteries
Solution Approach 1:
The system dynamically switches between two-wheel drive and all-wheel drive modes using clutches (504, 506) based on driving conditions. This dynamic adaptation allows the vehicle to use power efficiently by engaging all-wheel drive only when necessary, reducing overall energy consumption while maintaining adequate torque transmission capability.
Solution Approach 2:
The drive system is segmented into independent front and rear drive systems, each with its own clutch and differential. This segmentation allows selective engagement of front or rear wheels based on traction needs, optimizing energy usage by driving only the necessary wheels rather than all wheels continuously.
2Power
If additional or larger capacity batteries are used to supply power for the additional torque required by traditional gear arrangements, then the electric motor can generate sufficient torque, but the vehicle weight increases and range may still be limited
Solution Approach 1:
The system uses partial action by engaging the all-wheel drive system only when necessary rather than continuously. The clutches allow the vehicle to operate in two-wheel drive mode during normal conditions, requiring less total power output from the motor and thus reducing battery capacity requirements while maintaining adequate power availability when all-wheel drive is engaged.
3Loss of energy
If a transverse-mounted electric motor with parallel axis configuration is used, then torque can be transferred more efficiently to the wheels, but the gear arrangement complexity increases
Solution Approach 1:
The system merges the front and rear drive systems through a common planetary gear set (502) and propeller shaft (508), creating an integrated all-wheel drive system. This merging approach allows efficient torque distribution while sharing common components, thereby reducing overall system complexity compared to having completely separate drive systems.
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
Enhances the efficiency of the electric vehicle by optimizing torque distribution, thereby increasing the vehicle's range and potentially reducing battery capacity requirements.
Implementation Method 1
The planetary gear set includes a sun gear coupled to the output shaft, a plurality of planet gears coupled to a planet carrier and a ring gear, and the planet carrier is coupled to the second transfer shaft
Implementation Method 2
the brake is configured to lock the ring gear relative to a motor housing associated with the electric motor
Implementation Method 3
The ring carrier includes a bevel gear, the bevel gear is configured to couple to a first transfer pinion of a prop-shaft
Implementation Method 4
the first differential system includes a first differential ring gear and a differential housing that includes a plurality of spider gears that are configured to drive a pair of side gears
Implementation Method 5
the first clutch is coupled to the first differential ring gear and is configured to connect the first differential ring gear with the differential housing in the first state
Data Source
AI summary
An all-wheel drive system for a vehicle having a longitudinal axis includes an electric motor. The electric motor has an output shaft that extends along a first axis, and the first axis is substantially perpendicular to the longitudinal axis. The all-wheel drive system includes a first drive system including a first clutch and a first differential system configured to be coupled to a second drive system and to transfer torque to first wheels of the vehicle in a first state of the first clutch. The second drive system includes a second drive shaft and a second differential system. The second drive shaft is coupled to the output shaft and configured to transfer the torque to the second differential system. The second differential system is configured to transfer torque to second wheels of the vehicle, and the second differential system extends along a second axis substantially parallel to the first axis.