Electric Vehicle Charging Station with Monitoring - Electrical Engineering Guide
1. Introduction
Electric Vehicle (EV) charging stations are critical infrastructure for supporting electric mobility. This project focuses on building a prototype EV charging station with real-time monitoring of voltage, current, and energy consumption.
2. Objectives
• Design an EV charging system prototype
• Integrate monitoring for voltage, current, and energy
• Ensure safe, controlled charging through a microcontroller
• Enable basic data logging and display
3. System Overview
The system converts AC mains to regulated DC output for charging EV batteries. It includes sensors for monitoring electrical parameters, a microcontroller for control, and a display/interface.
4. Components Required
• Microcontroller (Arduino, ESP32, etc.)
• Voltage and current sensors (e.g., ACS712, ZMPT101B)
• Relay or solid-state switch
• AC-DC converter (power supply module)
• LCD/OLED display
• Resistors, capacitors, connectors
• Charging port or plug
• Casing and heat management
5. Block Diagram
Power Source → AC/DC Converter → Voltage/Current Sensors →
Microcontroller → Relay Control → EV Battery
↓
Display/Monitoring Unit
6. Working Principle
The AC mains is converted to a DC charging voltage. Sensors continuously monitor voltage and current. A microcontroller processes this data, displays it, and controls charging through a relay.
7. Power Supply and Conversion
An AC/DC converter supplies 12V or 24V DC for charging. Use appropriate heat sinks and ensure isolation from the control unit.
8. Microcontroller and Communication
The microcontroller reads analog/digital signals from sensors, calculates power and energy, and displays values. It can use UART or I2C for communication with displays or modules.
9. Monitoring and Data Logging
Real-time data from sensors is displayed on an LCD/OLED. Optionally, data can be logged using an SD card module or sent to the cloud using Wi-Fi.
10. Charging Modes and Control
Charging can be time-controlled, voltage-threshold based, or manually toggled. Relay modules are used to enable/disable the charging line.
11. Implementation Steps
1. Assemble circuit components on a breadboard or PCB
2. Program the microcontroller to read sensor data
3. Calibrate sensor readings
4. Implement relay control logic
5. Test with load before connecting real battery
12. Safety Considerations
• Use insulated enclosures
• Implement current/voltage limits in code
• Ensure thermal protection for power components
• Include a fuse or circuit breaker
13. Testing and Calibration
Test voltage and current readings with known loads. Use multimeter readings as reference to calibrate sensor data. Validate relay switching logic under load.
14. Applications and Use Cases
• Personal EV home charging stations
• Charging units in parking lots or offices
• Educational prototypes for energy management
15. Cost Estimation
• Microcontroller: $5–$15
• Sensors: $5–$10
• Power supply: $10–$20
• Display: $3–$5
• Relay module: $3–$6
• Total: ~$30–$60
16. Future Enhancements
• Mobile app integration for remote control
• Solar panel input option
• Cloud data logging and analytics
• RFID authentication for user-based access
17. Conclusion
An EV charging station with monitoring capability enhances user safety and energy tracking. This prototype forms the basis for scalable, intelligent, and connected charging infrastructure.