**2. Methodology**

Given that the past research was largely focused on the marine application of MCFC as the main power source for small-sized vessel, this research would be a record of the first research for investigating the practicability of MCFC for medium- and large-sized vessels. To achieve this goal, a 5,500 TEU class container ship was selected as a case ship, and its operating data was applied for the test bed simulation in order to analyze the power quality of the system.

For this research, a combined power source test bed composed of MCFC, battery and diesel engine was constructed. Based on the developed load scenario from the case ship, we analyzed the quality of voltage and frequency in response to the synchronization and de-synchronization between each power source in the test bed and evaluated whether the results could meet the current regulations. Figure 1 shows the outline of the research process.

**Figure 1.** Flowchart for research procedure.
