Design and Construction of a Wi-Fi-controlled solar inverter System

Abstract

Electricity generation from solar energy is made possible with the

use of a solar power system consisting of solar panels that absorb

sunlight, an inverter that converts DC to AC, and batteries that

store extra electricity. In this study, a 1 KW inverter system

controlled by a Wi-Fi network is constructed. ESP8266 Wi-Fi

module is set up to allow ATMEGA 328P microcontroller to

connect to a 2.4 GHz Wi-Fi network by generating an IP address

from any web server. The ESP8266 Wi-Fi module is programmed

on an Arduino platform to have a HIGH (ON) and LOW (OFF)

state to serve as a switch for controlling the inverter. This is

accomplished by connecting pin D5 of the ESP8266 Wi-Fi module

to the base of BC547 transistor, with the emitter of the transistor

connected to the negative terminal of the battery and the collector

is connected to one of the power pins of a 5 V relay, the other power

pin is connected to the positive terminal of the battery. The relay is

activated to switch when the transistor collector receives a

command from the base to change state. The high state opens the

transistor's channel to the relay, turning ON the inverter; the low

state turns the relay OFF, turning OFF the inverter. The system is

secured with a password to limit its use to those that have the

password. The inverter converted a 12V DC input into a 220V AC

output voltage at 50Hz. Switching the inverter to the ON and OFF

states is simple as it is controlled by a secured Wi-Fi connection.