Design and implementation of an automatic power factor correction system for domestic utilisations

Abstract

When an electrical installation is loaded by numerous inductive loads, the active power requires a current [Ia] necessary for the intended work. However, the reactive power also demands another amount of current [Ir] that serves no significant purpose, essentially making Ir a wasted current. Ideally, only Ia should be charged, but the electrical company bills for the total current [I], which includes both Ir (wasted) and Ia (used). Consequently, consumers end up paying more than they should. Therefore, power factor correction is necessary to improve the efficiency of the electrical system and address this issue. The power factor correction is generally done by introducing capacitor banks in the circuit. The capacitors will produce an inverse reactive current [–Ir] which will oppose and reduce Ir; capacitor banks are accurately sized according to some power range at a predefined limit current. This project targets to implement an automatic power factor correction unit mainly made by a PZEM 004T module, Arduino Uno, LCD display and electronic relays. The unit will permanently monitor the state of the electrical installation system, detecting at real time the drawn current I and power factor variation then a microcontroller (Arduino Uno) according to a program will decide how many capacitor banks to automatically introduce or remove from the electrical system in order to correct as better as possible the power factor. This study is made for a residential house of small consumers having at least a fridge, funs, mixers and other household appliances. This project can be resized, adapted and applied in industries, hotels, factories and any place where inductive loads are most used. The application of this project impacts positively the power production, consumption, financial expenses and further preserves and impact positively the climate change.