Battery Charging System Feedback Control Overvoltage Protection
Solution Overview
Problem
Existing charging systems for lithium ion rechargeable batteries face challenges in maintaining a high-setting voltage of the battery charger while ensuring a low overvoltage protection circuit setting value, which is necessary for safety standards, as decreasing the setting voltage affects full charge capacity and charging time.
Innovation Solution
A battery charging system that includes a voltage measurement circuit and an overvoltage protection circuit, with a control unit that generates a control voltage for feedback control of the battery charger's output voltage, using a corrected feedback voltage to prevent overvoltage protection circuit malfunction by adjusting the setting voltage and overvoltage setting value.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the battery charger setting voltage is increased to maintain high charging capacity, then the full charge capacity is improved, but the overvoltage protection circuit may malfunction due to voltage overlap with measurement errors
Solution Approach 1:
The patent implements feedback control by using the voltage measurement circuit to continuously monitor the battery cell voltage and feed this information back to the battery charger. The battery charger adjusts its output voltage based on the feedback signal, ensuring that the charging voltage remains within safe limits while maximizing charging capacity. This closed-loop control eliminates the need for conservative voltage margins.
Solution Approach 2:
The control unit acts as an intermediary between the voltage measurement circuit and the battery charger. It processes the measured voltage information and generates appropriate control signals to adjust the battery charger's output. This intermediary function enables precise voltage regulation by coordinating the measurements and control actions, resolving the conflict between high charging voltage and safety protection.
2Reliability
If a margin is provided between the battery charger setting voltage and overvoltage protection setting value to prevent malfunction, then the overvoltage protection reliability is improved, but the charging time increases due to lower setting voltage
Solution Approach 1:
The real-time feedback from the voltage measurement circuit allows the system to operate at higher charging voltages without requiring conservative margins. The feedback mechanism ensures that any voltage deviations are immediately detected and corrected, enabling the battery charger to maintain higher setting voltages safely, thus reducing charging time while preserving protection reliability.
Solution Approach 2:
The system performs self-monitoring and self-adjustment through the integrated voltage measurement circuit and control unit. The battery pack autonomously regulates its own charging voltage based on real-time measurements, eliminating the need for external conservative margin settings. This self-service capability allows optimal charging voltage to be maintained throughout the charging process.
3Reliability
If the overvoltage protection setting value is decreased to meet safety standards, then the safety margin is improved, but the battery charger setting voltage must also be decreased reducing charging efficiency
Solution Approach 1:
The feedback control system allows the battery charger to operate precisely at the optimal charging voltage determined by real-time battery cell voltage measurements. This eliminates the need to lower the setting voltage to meet safety standards, as the feedback mechanism ensures safe operation at higher voltages. Consequently, charging efficiency is maintained while safety standards are complied with.
Solution Approach 2:
The system dynamically adjusts the effective charging voltage parameter based on real-time battery cell voltage measurements and charging current conditions. By changing the voltage parameter adaptively rather than using a fixed conservative value, the system achieves both safety compliance and high charging efficiency. The control unit modifies the charging parameters to optimize both safety and productivity.
Data Source
AI summary
A battery charging system is disclosed. The battery charging system includes a battery cell, a voltage measurement circuit and an overvoltage protection circuit. The voltage measurement circuit measures a cell voltage of the battery cell. The overvoltage protection circuit is configured to stop charging the battery cell when a reading voltage measured by the voltage measurement circuit reaches an overvoltage setting value. The battery charging system also includes a battery charger for charging the battery cell, and a control unit for supplying a control voltage to the battery charger to perform feedback control of an output voltage of the battery charger. The battery charger includes a voltage feedback input for receiving a feedback voltage and a setting value input for receiving a setting voltage. The control voltage is generated based on the reading voltage and the setting voltage.