Assembled Battery Voltage Measurement Error Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional voltage measuring apparatuses for high-voltage batteries face accuracy issues due to variations in voltage for A/D conversion, leading to errors in digitized voltage detection across blocks of unit cells.
Innovation Solution
A voltage measuring apparatus with a block voltage detection unit, sampling voltage generation unit, A/D conversion unit, and voltage variation detection unit, which generates a sampling voltage, digitizes it, and calculates an error ratio to ensure high-accuracy measurement of unit cell voltages by recognizing and correcting errors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If voltage for A/D conversion is generated from each unit cell voltage, then the voltage measurement system can be simplified, but measurement precision deteriorates due to voltage variations causing digitization errors
Solution Approach 1:
The patent divides the battery into multiple blocks and introduces separate reference voltage sources for each block. This segmentation allows independent voltage reference management for each block, preventing error propagation across the entire system while maintaining modular simplicity.
Solution Approach 2:
The patent introduces a reference voltage as an intermediary element between the unit cell voltage and the A/D converter. This reference voltage acts as a stable mediator that decouples the variable unit cell voltage from the digitization process, ensuring accurate conversion without direct dependency on voltage fluctuations.
2Device complexity
If a single reference voltage is used for all blocks, then device complexity is reduced, but measurement precision deteriorates due to cumulative errors across blocks
Solution Approach 1:
The patent segments the reference voltage system into multiple independent reference sources, one for each block. This segmentation prevents cumulative errors from affecting all blocks simultaneously and allows localized error correction without system-wide complexity.
Solution Approach 2:
Each block is equipped with its own reference voltage source tailored to its specific electrical characteristics. This local quality approach ensures that each block's measurement system is optimized for its particular conditions, improving overall measurement precision without requiring a completely centralized complex system.
3Measurement precision
If voltage detection is performed for each unit cell, then measurement precision is improved, but device complexity increases due to multiple A/D converters
Solution Approach 1:
The patent merges the A/D conversion function into a centralized controller that receives voltage signals from multiple blocks. This consolidation reduces the total number of A/D converters needed while maintaining precise measurement capability through the use of local reference voltages for each block's voltage signal.
Solution Approach 2:
The patent uses reference voltage signals as intermediaries between the distributed voltage detection points and the centralized A/D conversion system. These reference voltages enable accurate digitization of multiple block voltages without requiring separate A/D converters at each detection point, thus reducing overall system complexity.
Data Source
AI summary
A voltage measuring apparatus for measuring an output voltage of an assembled battery in which a plurality of unit cells are connected in series and are divided into a plurality of blocks is provided. The voltage measuring apparatus includes: a block voltage detection unit which detects a voltage of at least one of the plurality of blocks; a sampling voltage generation unit which is provided in the block voltage detection unit and generates an analog sampling voltage applied in the sampling voltage generation unit; an A/D conversion unit which is provided in the block voltage detection unit and digitizes the analog sampling voltage to output a digital sampling voltage; and a voltage variation detection unit which obtains an error ratio of the voltage detected by the block voltage detection unit based on the digital sampling voltage.