Battery Rack Voltage Balancing via Sorting and Dynamic Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Battery packs with multiple cells connected in series face voltage imbalances due to manufacturing variations, leading to inefficient charging, potential overcharging or undercharging, and safety risks such as explosion, especially as the charging and discharging cycles increase.
Innovation Solution
A method that measures and sorts rack voltages, compares differences to set values, and automatically adjusts by charging or discharging specific racks based on counts to balance voltages, using a reference voltage and sorting algorithms like selective or quick sorting, allowing for parallel charging or discharging to minimize voltage deviations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If battery cells are charged in a lump irrespective of voltage differences, then charging process is simple, but voltage imbalance occurs leading to overcharging or undercharging
Solution Approach 1:
The patent divides the battery pack into multiple racks (first rack, second rack, etc.) and applies different charging/discharging operations to each rack based on its voltage level. This segmentation allows individualized voltage balancing while maintaining overall system manageability, resolving the contradiction between simple charging process and voltage balance reliability.
Solution Approach 2:
The patent implements dynamic charging/discharging control where the operation mode (charging or discharging) and sequence are adjusted based on real-time voltage measurements and comparison with reference voltage. This dynamic approach ensures voltage balance while adapting to changing battery states, preventing both overcharging and undercharging.
2Reliability
If manual voltage balancing is performed, then voltage balance can be achieved, but additional equipment, manpower, and time are required
Solution Approach 1:
The patent implements an automated voltage balancing system where the battery management system automatically measures voltages, compares them with reference voltage, determines charging/discharging sequences, and executes the balancing operations without manual intervention. This self-service approach achieves voltage balance while eliminating additional equipment and manpower requirements.
Solution Approach 2:
The patent incorporates continuous voltage measurement and comparison with reference voltage to provide feedback for automatic control. The system monitors voltage differences between racks and dynamically adjusts charging/discharging operations based on this feedback, achieving reliable voltage balance through automated closed-loop control without requiring manual intervention or additional complex equipment.
3Productivity
If voltage balancing is not performed, then charging process is fast, but safety risks such as explosion occur due to overcharging
Solution Approach 1:
The patent performs preliminary voltage measurement and comparison with reference voltage before initiating charging/discharging operations. By determining the appropriate charging/discharging sequence in advance based on voltage levels, the system prevents overcharging and undercharging before they can occur, eliminating safety risks while maintaining efficient charging throughput.
Solution Approach 2:
The patent implements rapid sequential charging/discharging operations across multiple racks in an optimized sequence. By skipping unnecessary delays and performing operations in parallel where possible, the system achieves fast charging speeds while the automated voltage monitoring and control prevent safety risks associated with overcharging.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Disclosed herein is a method of balancing rack voltages of a battery pack configured to have a structure in which a plurality of racks is connected in series or in parallel to each other, and a plurality of unit modules is connected in series to each other in each of the racks, the rack voltage balancing method including (a) a voltage measurement step of measuring voltages of the racks, (b) an sorting step of sorting the racks in ascending powers based on the voltage values of the racks, (c) a comparison step of comparing a difference between a maximum voltage value and a minimum voltage value with a set voltage, (d) a charging/discharging count step of comparing the voltage values of the racks with a reference voltage to increase a charging or discharging count, and (e) a charging/discharging step of charging or discharging the racks according to the charging or discharging count, wherein, in a case in which, at step (c), the difference between the maximum voltage value and the minimum voltage e value is lower than the set voltage, the racks are charged with the maximum voltage value without steps (d) and (e), and, in a case in which, at step (c), the difference between the maximum voltage value and the minimum voltage value is higher than the set voltage, steps (d) and (e) are carried out.