DBPapers
DOI: 10.5593/SGEM2014/B42/S19.051

IDENTIFICATION OF POWER FACTOR IN MARINE ELECTRICAL GRID

G. Nicewicz, M. Sosinski, D. Tarnapowicz
Wednesday 1 October 2014 by Libadmin2014

References: 14th International Multidisciplinary Scientific GeoConference SGEM 2014, www.sgem.org, SGEM2014 Conference Proceedings, ISBN 978-619-7105-16-2 / ISSN 1314-2704, June 19-25, 2014, Book 4 ,Vol. 2, 391-398 pp

ABSTRACT
The load factor of marine auxiliary engines is one of the basic information for the
calculation of air pollutants emission generated by ships. The load factors for different
types of ships, determining the results of emission calculations, are provided in various reports with greater or less approximation. For auxiliary engines, reports of the world’s organizations, dealing with air pollutants emissions, present statements of load factors depending on the type of vessel and operating conditions. These statements are prepared on the basis of data collected from registers of ships, log book records and interviews with captains of ships, chief engineers and officers of pilot stations. Determined in such a manner auxiliary engines load factors are not very precise. This is mainly due to the lack of empirical data on real operating load values of marine electric power systems. The data in the various types of reports sent periodically by chief engineers to ship owning companies technical services, supervising the operation of ships, are too residual. In addition, the load of marine generating sets read from power meters built in Main Switch Board or marine power plant alarm system control panel in Engine Control Room is not equivalent to the load of auxiliary engines. The load of auxiliary engine must be calculated taking into account the engine excess power factor to generator and the efficiency of generator. Unfortunately, in the case of data collected by the ship classification societies, there is no information on the efficiency of generators, the auxiliary engines excess power factors to generators or auxiliary engines continuous power, but only a nominal value of generating sets active power, understood as the active power of generators.
Therefore, the authors developed a method for determining the load factors of marine
auxiliary engines in ports in hoteling mode for different types of ships based on
identification tests of marine electric power systems load. Description of the method
and the results were presented in [1, 2]. The analysis [1, 2] were carried out for constant value of generator efficiency = 0.95 due to lack of operational data. Unfortunately, the efficiency of generator depends on the load and power factor (cosφ). The influence of character of marine generating load (cosφ) on generator efficiency will be analyzed in the paper based on the operational data from modern container ship in all operational conditions.

Keywords: emission of air pollutants by ships, load factor of marine auxiliary engines,generators efficiency