The Quality of Electricity Assessment in Marine Power Systems

The aim of the paper is to present some particularities of the electricity quality on board ships. The specific vulnerability of the naval power systems is given, first of all, by ship's power plant and its finite character. Power generation systems on board ships have, in their structure, a significant number of static power converters: controlled rectifiers, DC sources, DC power converters, inverters, etc. whose powers reach the order of tens of MW, comparable to the power of a ship's plant. The use of these devices in finite naval power plants, inevitably, produces a serious disturbance of the voltage and current waveforms, especially in the power consumer networks. The paper presents the theoretical framework of the problem as well as the results of measurements, which illustrate the presence of the disturbing harmonics due to the static converters.