Coaxial Motor-Generator Drive System for EV Weight Distribution
Solution Overview
Problem
Existing electric vehicle drive systems face challenges with weight distribution, limited adaptability to different vehicle types, and inefficiencies due to the large and complex structure of batteries and energy systems, particularly in hybrid vehicles and conventional battery swapping concepts.
Innovation Solution
A compact drive system with a motor and generator optimized for specific tasks, arranged coaxially with a gearbox, allowing for efficient energy conversion and adaptable to various vehicle types, featuring a cycloidal or planetary gear and integrated cooling and lubrication systems, with a control unit managing energy distribution and storage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a central generator is used to supply power to multiple drive motors, then the system can achieve coordinated power distribution, but the generator requires considerable space and has a complex structure
Solution Approach 1:
The patent divides the centralized generator system into multiple independent motor-generator units, with each wheel having its own dedicated unit. This segmentation eliminates the need for a large central generator while maintaining coordinated power distribution through independent control of each unit.
Solution Approach 2:
Each motor-generator unit is designed to perform multiple functions: it can operate as a motor to drive the wheel, as a generator to recover energy during braking, and as a standalone power source. This multi-functionality replaces the need for separate centralized power distribution components.
2Duration of action of moving object
If a hybrid vehicle combines a combustion engine and an electric motor with a voluminous accumulator, then the vehicle can achieve extended range, but the overall energy balance is not competitive due to the energy required to produce and integrate both systems
Solution Approach 1:
The patent implements a dynamic powertrain where each wheel's motor-generator unit can independently switch between motor mode and generator mode based on real-time driving conditions. This dynamic operation allows the system to optimize energy usage by recovering braking energy immediately and distributing power efficiently, improving overall energy balance while maintaining extended range capability.
3Object-generated harmful factors
If conventional batteries are used in electric vehicles, then the vehicle can achieve zero emissions operation, but the batteries only allow comparatively short vehicle ranges due to their low capacity
Solution Approach 1:
The patent enables continuous energy recovery and storage through the motor-generator units, which operate as generators during deceleration and braking to recharge the battery packs in real-time. This continuous energy replenishment extends the effective vehicle range while maintaining zero emissions operation, as the system continuously converts kinetic energy back into electrical energy.
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 solution provides a compact, efficient, and adaptable drive system that optimizes energy conversion and storage, enabling high torque and regenerative efficiency, while simplifying weight distribution and reducing installation space, thus enhancing vehicle performance and energy management.
Implementation Method 1
designed as a motor for driving the wheel during driving
Implementation Method 2
designed as a generator for charging energy stores during recuperation
Data Source
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AI summary
A drive system is disclosed for an electric vehicle having a drive module which has a generator and a motor which are arranged on a common axis. The generator and motor are assigned a transmission which also lies on this axis. Furthermore, a control unit for such a drive system having a motion controller which is assigned to multiple wheels and servo controllers which are respectively assigned to one wheel is disclosed.