Phase Angle Controlled AC-DC Converter

ESP32 Optocoupler ZCD MOC3021 BT136 Triac Phase Angle Control Bridge Rectifier UART IoT

Started: April 20, 2025

Completed: May 5, 2025

Duration: 2 Weeks

Project Overview

This project implements a phase angle controlled full-wave AC to DC conversion system. An ESP32 processes zero-cross signals from an optocoupler and adjusts the conduction angle of a BT136 triac via the MOC3021 driver. After controlling AC voltage, the output is rectified to DC. Alpha can be modified via UART commands or remotely through IoT integration.

Key Features

  • 🔸 Zero Crossing Detection: Uses optocoupler for accurate AC phase reference.
  • 🔸 Triac Triggering: MOC3021 drives BT136 triac to regulate AC conduction angle.
  • 🔸 Full-Wave Rectification: Bridge rectifier converts controlled AC to stable DC.
  • 🔸 Alpha Control: Adjust firing angle via UART or IoT for dynamic voltage output.
  • 🔸 IoT Monitoring: Real-time control and data logging over Wi-Fi.

Achievements

Demonstrated precise voltage regulation with ±5% accuracy.

Target Audience

  • 🔹 Power electronics engineers.
  • 🔹 IoT developers.
  • 🔹 Industrial automation specialists.
  • 🔹 Research & development teams.