EV Drive Battery Reconfiguration for Stable Traction Voltage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing drive devices for motor vehicles experience a significant decrease in drive power as the charge level of the traction battery decreases, leading to an undesirable reduction in performance.
Innovation Solution
The cell modules are divided into battery modules, with each battery module containing the same number of electrically parallel-connected cell modules, and these are connected in series between the connections to maintain a consistent electrical voltage that corresponds to the operating voltage of the traction machine, adapting the number of battery modules based on the charge level and discharge current to ensure consistent drive power.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the cell modules are connected in series to increase voltage, then the operating voltage matches the traction machine requirements, but the drive power decreases significantly as charge level decreases
Solution Approach 1:
The patent applies dynamics by making the battery configuration dynamic rather than static. The control device dynamically reconfigures the cell modules between series and parallel connections based on the charge level. When charge level is high, modules are connected in series to maximize voltage and power output. When charge level drops below a threshold, the system switches to parallel connections to maintain adequate voltage while preserving available capacity, thus maintaining consistent drive power throughout the discharge cycle.
2Power
If the cell modules are divided into battery modules with parallel connections, then the voltage remains stable, but the system complexity increases due to additional switching requirements
Solution Approach 1:
The patent applies segmentation by dividing the battery system into multiple independently controllable cell modules that can be selectively connected. Each cell module can be individually switched between series and parallel configurations through dedicated switching units. This segmentation enables flexible reconfiguration of the battery architecture to optimize performance while managing complexity through modular design, where each module operates as an independent unit that can be controlled separately by the central control device.
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
This approach maintains a high and consistent drive power regardless of the charge level of the traction battery, ensuring reliable operation of the traction machine by adjusting the electrical connections dynamically.
Implementation Method 1
the cell modules are divided up into battery modules, which each contain the same number of electrically parallel-connected cell modules
Implementation Method 2
these are connected in series between the connections to maintain a consistent electrical voltage that corresponds to the operating voltage of the traction machine
Data Source
AI summary
A method for operating a drive device for a motor vehicle, includes a traction battery having a plurality of cell modules and a drive unit which is designed as an electric traction machine and is electrically connected via an inverter to electrical connections of the traction battery. The cell modules can be electrically connected in different ways between the connections. The cell modules are divided up into battery modules which in each case contain the same number of electrically parallel-connected cell modules and are electrically connected in series between the connections. A number of the battery modules is adapted during operation of the drive device in such a way that an electrical voltage applied to the connections corresponds to at least an operating voltage of the traction machine.