Battery Parameter Characterization Using Augmented Dynamic Stimulus
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing battery modeling methods require computationally expensive offline characterization and lack sufficient spectral content in system load current for accurate estimation of equivalent circuit model parameters.
Innovation Solution
A method and system for online characterization of battery parameters using augmented dynamic stimulus, involving decomposition of battery voltage and current into sub-bands based on time constants, estimation of equivalent resistance and open circuit voltage, and intelligent generation of sink current to enhance spectral content.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If offline characterization is used to measure impedance across frequency range, then measurement precision is improved, but loss of time and computational complexity increase
Solution Approach 1:
The patent segments the frequency spectrum into multiple sub-bands and processes each sub-band separately using targeted excitation signals. This allows parallel processing of different frequency components, reducing overall characterization time while maintaining measurement precision through focused spectral analysis of each segment
Solution Approach 2:
The patent employs periodic excitation signals with specific frequencies corresponding to each sub-band. By using periodic stimuli and analyzing the periodic response, the system can efficiently extract impedance information across multiple frequency points through repeated measurements, reducing total characterization time compared to traditional sweeping methods
2Ease of operation
If system load current is used for in-situ characterization, then ease of operation is improved, but measurement precision deteriorates due to insufficient spectral content
Solution Approach 1:
The patent introduces an intermediary signal processing layer that analyzes the spectral content of system load current and identifies suitable frequency components for characterization. This intermediary analysis enables the system to extract useful impedance information from existing load patterns without requiring additional excitation hardware, maintaining ease of operation while improving measurement precision through selective spectral utilization
Solution Approach 2:
The patent dynamically adjusts characterization parameters based on the observed spectral content of system load current. When sufficient spectral content is present in the load current, the system activates in-situ characterization; when spectral content is insufficient, it adjusts timing or selection of sub-bands for analysis. This adaptive parameter adjustment maintains measurement precision while preserving the ease of in-situ operation
3Measurement precision
If augmented dynamic stimulus is generated to enhance spectral content, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent designs the augmented dynamic stimulus generation to serve multiple functions: it enhances spectral content for impedance characterization, maintains battery safety within operational limits, and adapts to different battery states. By making the stimulus generation system multi-functional, the patent improves measurement precision without proportionally increasing device complexity, as the same circuitry performs multiple protective and characterization roles
Data Source
AI summary
A method for intelligently generating a stimulus for use in characterization of parameters of a model of a battery may include dynamically analyzing a current drawn from the battery by a load, based on analysis of the current, determining a sink current for augmenting the current drawn by the load, and generating the sink current based on a determined need to update the parameters.