DC POWER SYSTEM FOR MARINE APPLICATIONS

A power system (100) for a marine ship includes a plurality of protection zones (102, 104), wherein at least two protection zones are coupled to each other via at least one bus-tie converter (106, 188). Each of the protection zones includes a plurality of direct current (DC) buses (120, 126, 150, 156) and a plurality of power converters (130, 136, 138, 160, 166, 168). The bus-tie converter includes at least two converter legs coupled by at least one inductor. Each converter leg includes a first branch connected with a snubber circuit. The first branch includes two outer switching devices and at least one inner switching device connected between the two outer switching devices. The first branch also includes a damping resistor coupled between the two outer switching devices to dissipate a fault current. The snubber circuit includes a combination of a diode, a resistor and a capacitor. A controller (180) controls the operation of the plurality of power converters and the at least one bus-tie converter.