Maintain the stability of the charging curve of the electric vehicle charger

Maintaining the stability of the charging curve of electric vehicle chargers is the key to ensuring charging efficiency, battery life and safety. The charging curve usually consists of two stages: constant current (CC) and constant voltage (CV), and its stability is affected by multiple aspects such as hardware design, software control, and environmental factors. The following are specific measures for maintaining the stability of the charging curve:

First, optimize the hardware design

Select high-quality power devices: Use high-precision, low-internal resistance MOSFETs, IGBTs and other power devices to reduce switching losses and heat generation, and ensure precise control of current and voltage.

Improve heat dissipation design: The heat dissipation performance of the charger directly affects its stability. Adopt efficient heat sinks, fans or liquid cooling systems to ensure the stable temperature of the charger during long-term high-power operation.

Optimize circuit layout: Reduce parasitic inductance and capacitance in the circuit and avoid high-frequency noise interference. Rationally arrange power lines, signal lines and ground lines to reduce electromagnetic interference (EMI).

Second, enhance the software control algorithm

Dynamic adjustment of charging parameters: Dynamically adjust the charging current and voltage based on the real-time status of the battery (such as SOC, temperature, and internal resistance) to ensure that the charging curve is always within a safe range.

Introduce PID control algorithm: Through the proportional-integral-derivative (PID) control algorithm, the output of the charger is adjusted in real time to reduce the fluctuations of current and voltage.

Implement a multi-stage charging strategy: Based on battery characteristics, design multi-stage charging curves (such as pre-charge, constant current, constant voltage, and trickle) to enhance charging efficiency and battery life.

Third, enhance the coordination of the battery management system (BMS)

Real-time communication and data sharing: A high-speed and reliable communication protocol (such as CAN bus) is established between the charger and the BMS to share battery status information in real time and ensure the precise execution of charging strategies.

BMS active intervention: When the battery malfunctions (such as overheating, overvoltage, or overcurrent), BMS should promptly notify the charger to adjust or stop charging to prevent potential safety hazards.

Fourth, environmental adaptability design

Temperature compensation function: In high or low temperature environments, the charger should be able to automatically adjust the charging parameters to prevent the charging curve from deviating due to temperature changes.

Input voltage fluctuation suppression: Use a power module with a wide voltage input range or add a voltage stabilization circuit to ensure the stability of the charger's output when the grid voltage fluctuates.

Fifth, regular maintenance and calibration

Regularly inspect hardware: Check the aging conditions of power devices, capacitors, inductors and other components, and replace damaged or performance-declining parts in a timely manner.

Calibrate charging parameters: Regularly calibrate the output current and voltage of the charger to ensure their accuracy meets the standard requirements.

Software update: Update the control software of the charger in a timely manner, fix known issues, and optimize the charging strategy.

Sixth, fault diagnosis and protection mechanism

Real-time monitoring and alarm: The charger should be equipped with a real-time monitoring function, capable of detecting abnormal parameters such as current, voltage, and temperature, and promptly sounding an alarm or taking protective measures.

Multiple protection mechanisms: including overcurrent protection, overvoltage protection, over-temperature protection, short-circuit protection, etc., to ensure the safety of the charger and battery in abnormal situations.

Seventh, standardization and certification

Adhere to industry standards: Ensure that the design and production of chargers comply with relevant international or domestic standards (such as IEC, GB/T, etc.) to enhance the compatibility and reliability of the products.

Third-party certification: Obtaining certifications such as CE, UL, and CCC proves that the safety and performance of the charger meet the requirements.