Transformer Protection and Monitoring System - Electrical Engineering Guide
1. Introduction
Transformers are critical components in electrical systems, and their protection and continuous monitoring are essential to ensure system reliability and safety. This project focuses on developing a microcontroller-based system to protect and monitor transformers.
2. Objectives
• Monitor transformer parameters such as temperature,
voltage, and current
• Provide automated protection during fault conditions
• Display status and fault notifications in real time
3. System Overview
The system uses sensors to measure key parameters, processes them using a microcontroller, and initiates protective actions like disconnecting the load or sounding alarms.
4. Functional Description
Temperature, voltage, and current are continuously monitored. Thresholds are set in the software, and any abnormal conditions trigger relays and alerts.
5. Key Components
• Microcontroller (e.g., Arduino, ATmega328P)
• Temperature sensor (e.g., LM35 or DS18B20)
• Voltage and current sensors (e.g., ZMPT101B and ACS712)
• Relay module
• LCD or OLED display
• Buzzer or alarm unit
6. Sensors and Signal Conditioning
Sensors output analog signals that are conditioned using resistors or op-amps and fed into the microcontroller’s ADC pins.
7. Microcontroller and Interfaces
The microcontroller reads sensor data, processes it, and drives the display, relays, and buzzer. Communication interfaces like UART or I2C can be used for data logging or external communication.
8. Protection Mechanisms
When parameters exceed limits, the system cuts power via a relay and activates alarms. It also logs the fault event if logging is implemented.
9. Monitoring and Display System
A display unit shows real-time data such as temperature, current, and voltage. Warning messages appear during fault conditions.
10. Software Implementation
Code written in C or Arduino IDE handles sensor reading, threshold comparison, relay control, and user feedback through display and buzzers.
11. Power Supply Design
A 5V DC regulated power supply using a transformer, rectifier, and voltage regulator (e.g., 7805) provides stable power to the control system.
12. Circuit Diagram and PCB Layout
Use design tools like Eagle or EasyEDA to prepare the schematic and PCB layout. Proper isolation and spacing must be ensured for safety.
13. Testing and Calibration
Each sensor must be tested for accuracy. Fault conditions should be simulated to verify the system's response and protection mechanisms.
14. Cost Estimation
Estimated cost: $25–$50 depending on the quality of components and features like logging and remote alerts.
15. Safety Considerations
• Use opto-isolators where necessary
• Proper fusing and surge protection
• Avoid direct connection to high-voltage terminals
16. Conclusion
This project offers a practical approach to transformer protection using embedded systems, improving safety and reliability with real-time monitoring and automated actions.