Harmonic characteristics on 20 kV - medium voltage distribution and low voltage network in PT. PLN distribution West Java and Banten

This paper describes the characteristics and levels of Harmonics on PT. PLN´s 20 kV medium voltage and low voltage distribution network in West Java and Banten. In this paper a study and measurements of harmonics for various types of loads in some types of industries are conducted and verified. This paper also discuss the phenomenon of harmonics, the effect on the distribution system, harmonic-producing sources, standards and recommended practice limits for medium voltage and low voltage network according to the IEEE 519 and IEC 61000 harmonic standard. Harmonic measurements methods were done on two types by measuring the customer´s 20 kV medium voltage and low voltage distribution substation network. The first method was done by measuring with continuous logging for a week duration on 8 samples of medium voltage customer to know the harmonics levels and their probability occurrence. The second method was done by instantaneous measurements for 5 minutes during peak load on 20 samples of low voltage distribution loads. From the measurement results shows that harmonic current conditions-THDi on the measured distribution substations are all above 5%, and 70% of customers who have THDi measured more than 10%. Other issues on the load harmonic currents that cause pollution to the harmonic current grid are also verified. The measurement of neutral current due to the harmonic currents in low voltage side of distribution transformer neutral circuit provides that 17 out of 20 samples measured were have larger value than the calculated condition without harmonics pollution.