SECTION 3 (4-f i —4)
Automatic Control System for Ships Electrical Power Plants
The first class period
Review of "Design and Operation of Power Plant Control System” and Nouns. 15
Topical content: Automatic control system for siiips electrical power plants. 10
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Automatic Control System for Ships Electrical Power Plants
!. The automatic control system is designed for controlling turbo- and diesel-driven electric generating plant, predominently onboard ships. The purpose of the automatic control equipment is to ensure that the power demand of a ship is generated in an economical manner and also to ensure that any faults occurring will not cause damage to the machinery. During fully automatic operation the equipment carries out starting, synchronizing and load sharing on one or several diesel alternators as the power demand increases; as well as disconnecting and stopping the diesel alternator in the event of excessive power being available. The starting of turbo alternator is usually done manually although synchronizing and load sharing is performed automatically. In the event of a fault on one set, a diesel alternator will automatically be started and connected to the main busbars. In the event of a serious fault, the set will
immediately be disconnected and stopped, this involving the danger of black-out. At black-out a programmed number of sets will be started and the set which is first to reach frequency will be connected to the busbars. The other diesels are then synchronized in the usual manner. A special unit in the automatic is available for program-blocking of connection of large loads, thus allowing the automatic equipment to ensure that there is always sufficient power available before the load is connected.
2. The system is designed for unmanned engine rooms (UER). The only manual operations needed are: starting up the turbos, selection of the sequence of diesel alternators, blocking of a set whenever this may be required, resetting of start blocking caused by an alarm, choice of a program with a minimum number of units in operation.
3. The automatic control equipment is designed to meet the requirements made by classification societies on equipment in unmanned engine rooms. This implies that some of the functions of the automatic control equipments are monitored so that au alarm will be initiated if the system is not entirely in functional condition.
4. The automatic control equipment can be connected to the general alarm system on board, provided that this system is designed for breaking contact functions during alarm conditions.