Excellent Custom «Marine Electrical Propulsion System» Free Essay

«Marine Electrical Propulsion System»


Marine electrical propulsion systems have advanced over the years. These innovations led to the effective marine vessel system operation. The introduction of electric propulsion resulted in environmental friendly means of marine transportation, which had a vast positive influence on the atmosphere, as well as on the health of the employees working on the ship. This paper explains why the AC power generator is important on the large cruise liner. The paper will furthermore demonstrate the strategies used by the cruising industry to have an efficient sailing of the cruise liner. Generator protection, synchronising, parallel operations, and voltage regulations are among the strategies in ensuring a safe cruising of the marine vessel. It is also important to have a speed control measures in the marine sector which will be described in the facets of droop control and isochronous control of the generator. 

AC Power Generation on Large Cruise Liner

The AC power generation on large cruise liner has particularly been advantageous in the marine industry. The machine produces high volume of electric flow which tends to consistently maintain the speed of the vessel. The AC electric power is stored in batteries for later use. The large cruise liner also has an emergency machine engine which is functional when the other machines may fail to work (Willis & Philipson, 2014). The ships also have a battery monitoring system that is efficient and notifies when any of the engines has mechanical problems. It is however important to note that the use of AC power causes less environmental harm. This mode of power generation exhibits less emission of hazardous chemicals into the air, which tends to affect the ozone (Whitaker, 2006). The use of the AC also helps in reducing the consumption of fuel. It is important to note that this source of power enables the machines to be easily maintained. This is primarily due to early detection of the machines failure by its monitors. The use of the AC current also exhibits its importance in ferrying bulky products. AC power has also improved the marine industry since it has reduced noise pollution which was produced when this type of power was not in place. Due to its environmental friendly facets and minor emission of green house gases, this technology may probably be the right direction in protecting aquatic life (Willis & Philipson, 2014).

Generator Protection

Generator protection in cruise liners is performed in various ways. Firstly, the main engines are separated from the propeller shafts (Molland, 2011). These engines are then connected to bigger generators which distribute the produced power to propeller shaft. This helps in maintaining the engines, as well as ensures that there is sufficient flow of power thus reducing the risks of a complete distraction of the whole system. The generator also stores power to ensure that the engine does not collapse. This is due to the fact that the generator also needs power in order to function effectively. The main engine is separated from another engine in a different room (Molland, 2011). This is done to ensure that the generator is protected from emergencies, for instance, from fre incident. In case of fire, other engines may collapse due to intense heat, but the larger generator may eventually survive and continue functioning. The generators are also turned off when they are not needed, that is when the ship is not moving. This helps the generator store its power for later use.

Generator Synchronisation

Generator synchronisation is done through assessment of the generator. In order to have a productive synchronisation of the cruise liner, the focus must primarily be on the frequency and voltage distribution of the generator (Ciezki & Ashton, 2000). The synchronisation of generator includes effective evaluation of the generators (Ciezki & Ashton, 2000). This comprises reflection on the generators electric circuit production. The assessment also ensures that it has data on the heat emission of the generator. Synchronisation of the generator also focuses on its design and parameters. The parameters ensure its efficiency and reduction in cases of generator destabilisation (Ciezki & Ashton, 2000).

Generator Parallel Operation

Parallel operation system is done through management and synchronisation of the generator systems. This includes power distribution in the machine where the time to start and stop the machine is established. This also controls the load to be accommodated within the cruise liner. The engine functions however should be the same so that the machines contribute to the work load functioning. This may include equitable electric propulsion (Gardner, 1994).

Generator Voltage Regulation

Generator regulations are mainly set to prevent people from being injured or in other words to ensure a safe travel. This safety parameter includes placing a separate room for the emergency engines which store energy (Gardner, 1994). They also secure the electric connection of the system in the cruise liner. The large cruise liner regulators are made to automatically maintain the consistent flow of voltage (Dannan, Day, & Kalman, 1973). This may prevent possible collapse of the ship and enable it to function effectively. The generator is also placed in a cool place so that it is not affected by any radiation heat (Ciezki & Ashton, 2000).

Regulation of voltage in cruise liner generators is performed through its regulators. The regulator maintains the flow of voltage in the ship. This actually helps the generator in maintaining its functions regardless of the load it carries. The regulator also ensures that the flow of voltage is sufficient and flexible. Prevention of insufficient flow can be done by starting and stopping of the regulator automatically (Dannan, Day & Kalman, 1973). This helps to avoid lack of power at any moment. This is categorically important since the ship needs electricity for its functioning. The voltage regulator also ensures that the change in speed is accompanied with the change in its magnetic field (Dannan, Day & Kalman, 1973). The change in the magnetic field ensures that gravitational pull is stabilised in order to prove that the cruise liner has a balance on the water (Willis & Philipson, 2014).

Droop Controls of AC GGenerators

Droop control basically involves speed control of the marine vessel. Here the generators work parallel together. This means the weight load is shared to the generators depending on their abilities. Generators with powerful engines are allocated for bigger loads as compared with weaker ones. The droop control is summarised by frequency, speed, and load. It is stated that frequency of a synchronous AC generator is directly proportional to the speed of the rotating field (Whitaker, 2006).

Isochronous Controls of AC Generators

Isochronous control is the mode in which speed is combined to frequency. In this mode, regulation is performed so that the movement of the vessel reflects on the load. In other terms, change of the load would influence change of the frequency. If heavy loads are placed on the generator, there would be a change in speed but basically the isochronous control enhances the speed of the vessel (Whitaker, 2006).

Comparison between Droop Controls and Isochronous Controls of AC Generators

Both droop and isochronous controls involve regulation of heavy loads. The droop and isochronous controls tend to enhance the efficiency of the moving vessels. They act as equilibrium balancing the speed of the moving vessel with the load they are carrying (Whitaker, 2006). This is shown by the characteristics they exhibit. For instance, a change in load weight leads to a change in motion (Whitaker, 2006). An energy emission from the generator to the moving body is also reflected at the speed of the vessel. Machines that are operational to isochronous speed control mode are usually connected to the droop speed control mode. These controls ensure that the vessel efficiency is stabilised even under no human supervision (Whitaker, 2006).

Mode Used in Cruising 4 by 15 KVA Alternators

The 4 by 15 KVA alternators have been established in order to withstand most of the harsh oceanic conditions. They are reliable in carrying heavy load through tough terrain. The 4 by 15KVA motors are constructed with magnetic engines (Dannan, Day & Kalman, 1973). The permanent magnet would be helpful in this transport system since it maintains a steady flow of power. The power to be used should be steam or gas power since they usually give the best results in cruising. It is also important to ensure that the technology use is suitable for cruising cargoes (Dannan, Day & Kalman, 1973).


The use of AC power has positive outcomes in the cruising industries including reduction of pollutants emission. This particularly helps in reducing noise pollution. The use of the AC power engine however has shown that though they are expensive, the positive impacts are overwhelming. The use of this power has made the cruising industry relevant due to the fact that it ensures safe trips to their clients with the help of its efficiency and established parameters. A close monitoring of the cruise liners functioning has shown its importance in the reduction of hazardous cases. On personal ground this form of transportation should be used in the diverse countries globally.


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