Section 8.1 Overview
An overview of the electric propulsion system of the Patriot State II is shown in the one-line diagram below, Figure 8.1.1.
Electrical power for both propulsion and ship’s services is produced by four Hyundai HSJ9 913-08P diesel driven generators. These are 6600 Volt, three-phase AC synchronous generators capable of producing up to 4053 kW at 80% power factor, or 5066.25 kVA.
Generators 1 and 2 are located in engineroom 1 and directly feed main switchboard No.1, and generators 3 and 4 are located in engine room 2 and feed main switchboard No. 2. The switchboards can be split or cross-connected as necessary for emergency operations.
Each switchboard supplies electrical power at 60 Hz, 1850 Volts to a Propulsion Converter via a step-down transformer. The purpose of the propulsion converters is to change input voltage and frequency to the voltage and frequency needed to spin the propulsion motor in the desired direction, at the desired speed, as ordered by the bridge.
Each propulsion converter provides power to a Propulsion Motor. The two propulsion motors drive a common shaft which is directly connected to the ship’s single propeller, as shown in Figure 8.4.2.
The generators, transformers, propulsion converters, and propulsion motors will be discussed in more detail in the sections that follow.
