Design and Implementation of IoT Based Grid-Tied Inverter for Micro-Grid System

This paper describes the design, simulation, and implementation of an IoT-based grid-tied SPWM inverter that converts supplied DC voltage to pure sinusoidal (AC) voltage based on the voltage and frequency of the local grid (240 volts and 50 Hz), while additionally offering an IoT interface and web control. The purpose of this study is to use a cost-effective and powerful Arduino Nano (8-bit AVR microcontroller) to produce the widely used SPWM with a very high carrier frequency (10 kHz) to operate the inverter circuit. Using small capacitors and inductors, SPWM's high-frequency pulses provide smoother filtering of inverter output into pure sinusoidal waves. Zero-crossing detector circuitry is used for grid synchronization. The circuit is to detect the grid phase, and the code is doing a task by using Software Phase Loop Lock (SPLL). The IoT interface is done by using the ESP8266, Arduino, Relay, and ThingSpeak platforms. Inverter voltage ranges in grid mode are 220-255 volts; frequency ranges are 49.20–51.60 Hz; and in island mode, voltage and frequency are 240 volts and 50.00 Hz, respectively. ThingSpeak provides the collection, storage, visualization, and analysis of live data streams on its platform. The web control relay provides remote load control facilities as well as easy operation and monitoring facilities.