Investigation the effect of neutral current and harmonic at laboratory building

Abstract

This project is aimed to study and identify power quality related neutral current and harmonics effects in the Muhibah laboratory building. In this project, it will analyze the quality of the power distribution board in which supply power to the laboratory equipment. The equipment that use along the monitoring is Three Phase Power Recorder (Fluke 1750) to obtain an overview of the resulting waves throughout the analysis performed. From the resulting waveforms, the analysis will be made to identify the quality level of power that occurred in the laboratory building is mainly related to the input is not stable especially that related on harmonics and non-linear loads occurs. This project mainly to monitoring and investigate power quality problem occur at the building. The available of lab contained with the linear load and non linear load (lighting system, air-conditioner system, computer, measurement meter etc.) in the building make contribution of power quality problem others than incoming power problem from provider. In this final year project, a study of neutral currents in threephase distribution network with non-linear loads is presented. Studies show that the magnitude of the neutral current in three-phase computer power systems depends on the harmonic content and phase balance of the load currents. Power system problems associated with high harmonic neutral currents include overloaded four-wire power feeders and branch circuits, overloaded transformers, voltage distortion, and common mode noise. Whenever three-phase, wye power systems are used to supply power to computer systems, the power system design should allow for the possibility of high harmonic neutral current to avoid potential problems. All the objective of this final year project has been achieved. To prove the theory, the monitoring of non-linear three-phase supplying single phase loads has been done. From the monitoring result, there has been approving that neutral conductor of non-linear load has a lot of neutral current.