Battery Insulation Monitoring Circuit With Integrated Voltage Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Battery management systems for electric vehicles face increased costs due to the need for separate circuits for insulation resistance measurement and high-voltage monitoring, which are not efficiently integrated.
Innovation Solution
A battery unit and management system that integrates insulation resistance measurement and high-voltage monitoring circuits using a processor and resistors to measure voltage and insulation resistance, reducing the need for separate components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If insulation resistance measurement is performed using a battery management system, then safety monitoring capability is improved, but measurement accuracy deteriorates due to voltage drops across connection terminals and conductors
Solution Approach 1:
The patent introduces a test terminal as an intermediary component specifically for insulation resistance measurement. This test terminal is connected to the battery module terminals through isolation switches, creating a dedicated measurement path that separates the measurement function from the power transmission path, thereby eliminating voltage drop errors from affecting the measurement accuracy.
Solution Approach 2:
The patent segments the battery management system into distinct functional modules: a test terminal for measurement, isolation switches for circuit control, and a microcontroller for data processing. This segmentation allows the insulation resistance measurement to be performed independently without interference from the battery's operational voltage and current paths.
2Ease of operation
If connection terminals and conductors are used in the battery management system, then system connectivity is improved, but measurement error increases due to voltage drops
Solution Approach 1:
The test terminal serves as an intermediary measurement interface that is electrically isolated from the battery terminals. This allows voltage measurements to be taken across the test terminal rather than directly across the battery terminals, eliminating the impact of voltage drops in the connection terminals and conductors on the measurement accuracy.
Solution Approach 2:
The patent replaces direct mechanical electrical connection for measurement with an electrical signal-based measurement system. The microcontroller measures voltage across the test terminal and calculates insulation resistance through computational processing, substituting direct electrical measurement with electronic signal processing to eliminate physical connection errors.
3Adaptability or versatility
If insulation resistance measurement circuit is integrated into battery management system, then measurement functionality is improved, but device complexity increases
Solution Approach 1:
The test terminal and isolation switches are designed to serve multiple functions: they enable insulation resistance measurement, provide circuit isolation for safety, and can be controlled by the microcontroller for various testing scenarios. This multi-functionality reduces the need for separate dedicated components, thereby limiting the increase in device complexity while enhancing measurement functionality.
Solution Approach 2:
The battery management system performs self-diagnosis through the integrated insulation resistance measurement circuit. The microcontroller automatically controls the isolation switches and measures voltage across the test terminal to assess battery health, eliminating the need for external measurement equipment and simplifying the overall system architecture.
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 integration reduces the overall cost of the battery management system while maintaining effective insulation resistance monitoring and high-voltage monitoring capabilities.
Implementation Method 1
the voltage measurement unit, configured to measure a voltage between the first test terminal and the second test terminal
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A first insulation resistance monitoring circuit includes a first resistor that is connected between the positive terminal of a battery pack and a node, and is connected between the positive terminal of the battery pack and a ground terminal of an external device, and has a first monitoring terminal. A second insulation resistance monitoring circuit is connected between the ground terminal and the negative terminal of the battery pack, and has a second monitoring terminal. A voltage monitoring circuit is connected between the node and the negative terminal of the battery pack, and has a third monitoring terminal. A processor measures the voltage of the battery pack on the basis of the voltage of the third monitoring terminal, and measures first insulation resistance which is formed between the positive terminal of the battery pack and the ground terminal and second insulation resistance which is formed between the negative terminal of the battery pack and the ground terminal, on the basis of the voltage of the first monitoring terminal and the voltage of the second monitoring terminal.