Study of Electric Power Quality Improvement in Ship Networks

In this paper, the reason for the deterioration of electric power quality in ship networks these years is discussed. And the necessity of improvement of marine power quality is described considering the effects of this phenomena on economical operation of ship and reliability of marine systems. Afterwards, the criteria of power quality that have been issued in China are introduced, as well as the specific demands on marine power quality. Then, relevant solutions which are applied nowadays to improve power quality of electric network according to the five aspects of power quality - harmonics, fluctuation and flick of voltage, voltage deviation, unbalance of three-phase voltage and current, frequency deviation - are discussed. Finally, the applicability of the employment of the relevant solutions to marine electric power system is discussed, and a new solution that is more suitable for marine use is proposed after its theoretical analysis