Shore to ship converter system for energy saving and emission reduction

In the shipping industry, people are paying more attention on the emission issue of ships. A shore to ship power solution is attractive for port authorities and ship owners as it helps to reduce emissions in ports by connecting ships to the port electricity grid and turn off their diesel engines while at berth to improve air quality, reduce noise and vibrations in port areas. Besides, there are also economical benefits of shore to ship power as costs related to fossil fuel consumption increase. Because most ships operate with 60 Hz electricity whereas local grid in most parts of the world is 50 Hz, shore-to-ship power is required to transfer power between two different grid systems. Although some old technologies such as rotating motor/generator systems are capable to realize frequency conversion, the static frequency converter system has obvious advantages to serve as power supply today for its small size, high reliability, low losses and low civil work requirements. In this paper, PCS 6000, a medium voltage (MV) frequency converter, is introduced. By using the proven converter technologies, the proposed shore to ship power solution can realize the frequency conversion smoothly with power range from 4 MVA to 120 MV A. In this paper, firstly, the background of shore to ship power is introduced, including the overview of shore to ship power related regulations and standards. The technologies of shore to ship power, especially frequency converter system are investigated. The components, topologies and power control methods of the proposed MV frequency converter are presented. Finally, the features of the proposed converter are illustrated.