Harmonic Analysis due to Reconfiguration of Shipboard AC to DC Electrical Distribution System with Hybrid Energy Sources

This study conducted a harmonics analysis on the tanker ship electrical system. Harmonics is analysed for two types of electrical distribution system, namely AC and DC system which also adopt hybrid diesel generator and photovoltaic as the energy sources. The analysis is divided into four ship operation modes, consist of at port, leaving arriving, loading unloading, and sailing. The analysis was carried out to know the effect of reconfiguration from AC to DC distribution system and the addition of photovoltaic to the total harmonics distortion (THD). The analysis was carried out using a power system simulator software. The results show that the DC distribution system has a larger THD than the AC. The largest THD found in the AC distribution system is 5.38% while it exceeds 12% in the DC system. Other than the largest, several other buses in the DC system also exceeding 8% limit of THD regulated by Indonesian classification bureau (BKI). Considering other advantages of DC system, the disadvantage in the harmonics should be handled by installing harmonic filter. In this study case, the THD in the DC system can be reduced to less than 3% by installing 13 kVAR harmonic filter.