MARINE & OFFSHORE Setting sail for innovation
Marine & Offshore Test now even faster
The electrical power system of ships has long been based on alternating current (AC) system. However, similar to aviation, marine engineers have begun to question the efficiency of the AC on-board system, which used to be taken for granted. They have tried to find a more efficient and environmentally friendly power distribution system. Following the trend of battery- and fuel-cell-powered cars, the marine industry has now introduced the direct current (DC) system for the electrical distribution system and the powertrain in ships in combination with the AC on-board electrical system.

Energy Recovery: Renewable Power Supplies and Sources
As manufacturers of all types of mechanical devices work towards efficient energy use, renewable energies have taken on an important role in reducing operating costs. Energy recovery recovers kinetic energy generated by a motor when stopping or braking. This then requires the conversion of this energy into electricity in order to return it to the power grid. Hybrid and electric vehicles are the most obvious examples, and other applications that require frequent stopping and starting – such as cranes, elevators and spindle drives – can also use significant amounts of kinetic energy for power recovery.

This also applies to electronic tests. Because energy efficiency is critical for those who perform high-performance testing, power customers need to factor in operating costs over the lifetime of a product. These often exceed the initial investments. Today, providers of renewable power supplies and sources not only market the low operating costs of their solutions. Many newer solutions are also characterized by a smaller space requirement, have a low heat dissipation and convince with a minimum maintenance effort.

EA's regenerative bidirectional power supplies are uniquely suited to the marine industry. This applies to the power control systems for photovoltaic inverters and backup batteries as well as to the submarine battery test for hybrid controllers. Below you will find links to the products used in the [Name Application]: PSB bidirectional DC supply, ELR regenerative electronic DC load and PSI conventional programmable DC power supply.

Products used in Marine & Offshore:

• DC Bidirectional Laboratory Power Supplies
• Electronic laboratory power supplies
• Programmable DC Electronic Laboratory Power Supplies

Electric drive
According to the United Nations Conference on Trade and Development, ships transport about 80 percent of the world's goods. And transport across the oceans will continue to increase in the coming years – by 3.8 percent per year until 2022. However, ships produce a huge amount of exhaust gases such as sulfur oxides, nitrogen oxides, soot particles and particulate matter, as well as carbon dioxide (CO2). Most container and cruise ships, oil tankers and cargo ships run on heavy diesel oil. And they consume enormous amounts of it: The 90,000 ships worldwide burn a total of 370 million tons of fuel per year – and produce 20 million tons of sulfur oxide. Therefore, electrification is necessary to remove these heavy pollutants from the shipping industry.

Three main streams of ship electrification:

• Diesel-electric drive: Diesel generators generate the electricity. The current drives the electric motor that moves the ship's propeller.
• Hybrid drive: In addition to the combustion engine, batteries are on board. On the one hand, they can also be switched on for a short time if a power peak is required. On the other hand, they can store excess energy, for example from the diesel generator. For a while, the ship could only sail on electricity.
• All-electric drive: There is no combustion engine on board, all the energy comes from batteries.

EA Benefits:

• Output voltage up to 2000V
• Power output up to 30 kW
• Parallel connection of up to 2MW
• High power density

Cathodic corrosion protection
Cathodic corrosion protection in naval vessels is also powered by programmable DC power supplies to prevent deterioration of the ship's steel body. Cathodic protection on ships is often realized by galvanic anodes on the hull and ICCP for larger ships. Since ships are regularly taken out of the water for inspection and maintenance purposes, it is a simple task to replace the galvanic anodes. Galvanic anodes are usually shaped to reduce resistance in the water and close flush with the hull to minimize resistance.

Smaller ships with non-metallic hulls, such as yachts, are equipped with galvanic anodes to protect areas such as outboard engines. As with any galvanic cathodic protection, this application relies on a solid electrical connection between the anode and the object to be protected. For ICCP on ships, the anodes are usually made of a relatively inert material such as platinum-plated titanium. A DC power supply is provided inside the ship, and the anodes are mounted on the outside of the hull.

The anode cables are inserted into the ship via a clamping screw connection and fed to the DC power source. The negative cable of the power supply is simply attached to the fuselage to close the circuit. Ship ICCP anodes are flush mounted to minimize the impact of air resistance on the vessel and are located at least 5 ft below the low load line in an area to avoid mechanical damage. The current density required for protection is a function of speed and is taken into account when selecting the current capacity and the position of the anode arrangement on the ship's hull.

Some ships may require special treatment, e.g. aluminum hulls with steel fasteners create an electrochemical cell in which the aluminum hull acts as a galvanic anode and corrosion is enhanced. In such cases, galvanic anodes made of aluminum or zinc can be used to compensate for the potential difference between the aluminum hull and the steel internals. If the steel brackets are large, multiple galvanic anodes may be required, or even a small ICCP system.

EA Benefits:

• Output voltage up to 2000V
• Power output up to 30 kW
• Parallel connection of up to 2MW

Magnetic sound attenuation – demagnetization
A ship with a steel hull is like a huge floating magnet surrounded by a large magnetic field. As the ship moves through the water, this field also moves and adds or subtracts to the Earth's magnetic field. Because of its distorting effect on the Earth's magnetic field, the ship can serve as a trigger for magnetically sensitive devices designed to detect these distortions. The demagnetization system will be installed on board the ship to reduce the ship's effect on the Earth's magnetic field. To achieve this, the change in the Earth's magnetic field around the ship's hull is "reversed" by controlling the electric current flowing through demagnetization coils wound at certain points within the ship's hull. This, in turn, reduces the possibility of magnetically sensitive guns or devices being detected.

EA Benefits:

• Output voltage up to 2000V
• Power output up to 30 kW
• Parallel connection of up to 2MW
• High power density

Sea Mine – Tracking the ship's magnetic signature
Modern mines affect the ocean by detecting magnetic interference from a ship in the Earth's magnetic field. This is called the magnetic signature of the ship. This signature is the main influence used to trigger the sea mine or torpedo. If the signature is detected and analyzed, then the ship is identified and the magnetic signal becomes the trigger for torpedo or mine explosion, indicating a position and categorization (mainly submarine). To minimize this threat, the ship is equipped with a built-in demagnetization system (DG). DG reduces the signature with a counter-action field generated by a play system connected to the loop coil power amplifier.

EA Benefits:

• Output voltage up to 2000V
• Power output up to 30 kW
• Parallel connection of up to 2MW
• High power density

Electrified submarine
The polymer electrolyte membrane (PEM) fuel cells from Siemens Marine are the future for electrical power generation in submarines that does not require outside air. Since the cells only need hydrogen and oxygen as fuel, dive times can be significantly extended. This makes submarines equipped with these low-temperature fuel cells far superior to conventional submarines, which have to appear relatively frequently to recharge their batteries. These new designs are much more efficient and do not emit any exhaust gases. Thanks to its electrochemical mechanism of action, which generates only water and heat in addition to electricity, the PEM fuel cell does not cause any noise. Their rugged, low-signature and non-magnetic design is specifically designed for long-term use and has an expected lifespan of many years – all in an effective and affordable lifecycle support package.

EA Benefits:

• Output voltage up to 2000V
• Power output up to 30 kW
• Parallel connection of up to 2MW

Navigation
Maritime cathodic protection extends to many areas such as jetties, ports and offshore structures. The variety of different types of structures leads to a variety of protection systems. Galvanic anodes are preferred, but ICCP can also be used frequently. Due to the great diversity of structural geometry, composition and architecture, specialized companies are often required to develop structure-specific cathodic protection systems. Sometimes marine structures require retroactive modification to be effectively protected.

EA Benefits:

• Output voltage up to 2000V
• Power output up to 30 kW
• Parallel connection of up to 2MW

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Power Electronics “made in Germany
EA Elektro-Automatik GmbH & Co. KG is Germany’s leading manufacturer of laboratory power supply, high-performance power supplies and electronic loads. In 1974 Helmut Nolden founded the company with the vision to develop highly qualified power supply systems for all applications.