Designs of harmonic filtering system for minimizing the harmonic effects and improve the power factor

Abstract

Now a day, power quality is becomes more and more important issue. The whole Malaysia energy consumers concerned about the quality of energy they are using, and the consumers are enjoying with the outstanding performance from Tenaga Nasional Berhad. However, what the consumers probably more concern is the electricity bill that has to pay for every month. This project introduces harmonic filtering system for minimum harmonic effect and by the way, improves the power factor. Two types of harmonic filtering system are presented, the first one is passive band-pass filter (RLC circuit), and the second one is active multiple feedback band-pass filter (operational amplifier with capacitor and resistor). Both systems are discussed, and comparative studies are performed based on their ease of applications, economic aspects, and effectiveness. By designing the necessary techniques and methodology, the overall total harmonic distortion (%THD) and power factor can be improved to the expectation. Both harmonic filtering system are applied in three phase. The AC three phase supplies is directly from TNB with 415V line to line voltage star connection. Schaffner NSG 1007 Programmable Source is being used to control the input voltage to the filtering system by the assist of Win 2110 software. This software provides many types of functions such as harmonic analysis and power factor measurement. From the experimental results obtained, the %THD would be reduced by 5% with passive filter and 10% with active filter. Power factor will also be increased 10% due to decreasing in %THD.