Hybrid AWD Torque Distribution During Engine Restart Transitions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing three-motor hybrid all-wheel-drive systems face increased costs, weight, and degraded fuel economy due to a complex system and spin loss, necessitating a two-motor system that can perform front-rear driving-force distribution effectively.
Innovation Solution
A hybrid all-wheel-drive vehicle with an engine, first and second motor generators, and clutches, controlled by a control unit to manage torque distribution and engine restarts, ensuring balanced front-rear driving forces during mode transitions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a three-motor hybrid all-wheel-drive system is used, then front-rear driving-force distribution capability is improved, but device complexity and cost increase
Solution Approach 1:
The patent combines the functions of three separate motors into a two-motor configuration by integrating the first motor generator with the engine and using the second motor generator to drive both front and rear wheels through clutch mechanisms. This merging approach maintains all-wheel-drive capability while reducing system complexity and component count.
Solution Approach 2:
The second motor generator is designed to serve multiple functions: it can drive the rear wheels directly, transmit power to the front wheels through the first clutch, and provide torque to the engine through the second clutch for hybrid operation. This multi-functionality eliminates the need for a dedicated rear motor while maintaining all-wheel-drive capability.
2Adaptability or versatility
If a three-motor hybrid all-wheel-drive system is used, then driving performance is improved, but weight increases
Solution Approach 1:
The patent merges the function of the third motor (rear motor) with the second motor generator, which already serves the front wheels and engine. By using a single motor generator to power multiple components through clutch mechanisms, the overall motor weight is reduced while maintaining all-wheel-drive performance.
3Adaptability or versatility
If a three-motor hybrid all-wheel-drive system is used, then all-wheel-drive capability is improved, but fuel economy degrades
Solution Approach 1:
The patent combines multiple powertrain functions into fewer components, reducing the total number of motors from three to two. This reduction decreases parasitic losses and improves fuel economy while maintaining all-wheel-drive capability through intelligent clutch control and power distribution strategies.
Solution Approach 2:
The system dynamically changes operational parameters by controlling clutch engagement and disengagement, allowing the vehicle to switch between two-motor hybrid mode and two-motor AWD mode. This parameter control optimizes fuel economy by engaging all-wheel-drive only when necessary while maintaining the capability when needed.
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 achieves desirable front-rear driving-force distribution and efficient regeneration, maintaining vehicle stability during mode shifts by balancing torque distribution and engine operation.
Implementation Method 1
a first motor generator MG1 that is coupled to the engine in a manner capable of transmitting torque and is coupled to the front wheel in a manner capable of transmitting torque
Implementation Method 2
a second motor generator MG2 that is coupled to the front wheel in a manner capable of transmitting torque and is coupled to the rear wheel in a manner capable of transmitting torque
Implementation Method 3
a first clutch C1 that is interposed between the second motor generator and the front wheel and a second clutch C2 that is interposed between the second motor generator and the rear wheel
Data Source
AI summary
A hybrid all-wheel-drive vehicle includes an engine, first and second motor generators, a first clutch between the second motor generator and a front wheel, a second clutch between the second motor generator and a rear wheel, and a control unit that controls, based on a vehicle traveling state, the engine, the motor generators, and the clutches. The first motor generator is coupled to the engine and the front wheel in a manner capable of transmitting torque. During regeneration, the control unit engages the first clutch and disengages the second clutch. When the all-wheel-drive vehicle shifts from motor traveling to hybrid traveling, the control unit restarts the engine by operating the first motor generator and regulates engagement forces of the clutches and output torque of the second motor generator to compensate driving torque of the front wheel by the second motor generator while maintaining driving torque of the rear wheel.