Synchronized Battery Pack Voltage and Current Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for measuring current and voltage of secondary battery packs struggle to accurately synchronize measurement time points, leading to incorrect internal resistance estimation and processor overload in battery management systems, especially in electric vehicles and hybrid vehicles.
Innovation Solution
An apparatus and method that synchronizes current and voltage measurement time points using a control unit to adjust sampling periods, calculating time differences and errors to ensure precise measurement of current and voltage, thereby accurately estimating internal resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If current measurement is performed frequently to synchronize with voltage measurement for accurate internal resistance estimation, then measurement precision is improved, but processor overload increases and operating reliability deteriorates
Solution Approach 1:
The patent applies preliminary action by pre-calculating and storing the time difference between current and voltage measurement time points. This allows the system to synchronize measurements without performing complex real-time calculations during operation, reducing processor load while maintaining measurement accuracy for internal resistance estimation
Solution Approach 2:
The patent changes the measurement parameter approach by using the time difference (Δt) between current and voltage measurements as a key parameter. Instead of continuously synchronizing measurement time points, the system calculates internal resistance using the formula R = (V2 - V1) / (I1 - I2) - dV/dt * Δt, where Δt is the pre-determined time difference. This parameter change allows accurate measurement without requiring simultaneous measurement time points, reducing processor overhead
2Measurement precision
If current measurement cycle is shortened to synchronize with voltage measurement, then measurement precision is improved, but processor operating speed reduces
Solution Approach 1:
The system performs preliminary action by pre-determining the time difference between current and voltage measurement time points during system initialization or calibration. This eliminates the need for continuous real-time synchronization calculations, allowing the processor to maintain higher operating speeds while still achieving accurate synchronized measurements when needed
Solution Approach 2:
The patent implements feedback by using the time difference information from previous measurements to adjust and maintain synchronization in subsequent measurements. The system continuously monitors the time difference between current and voltage measurements and uses this feedback to maintain accurate synchronization without requiring the processor to perform intensive real-time calculations, thus preserving processing speed
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided is an apparatus for measuring current and voltage of a secondary battery pack in synchronization manner, comprising a voltage measurement circuit for periodically measuring and outputting the level of a charging voltage of each of a plurality of battery cells contained in a battery pack; a current measurement circuit for periodically measuring and outputting the level of current flowing into or out of the battery pack; and a control unit for synchronizing a time difference between a current measurement time point of the battery pack and a voltage measurement time point of each battery cell with a reference delay time.