Bakker Sliedrecht develops generator protection for dual-fuel ships

(SLIEDRECHT, Netherlands) — Bakker Sliedrecht has developed a generator protection system for dual-fuel vessels which operate with a dynamic positioning systems (DP) 2 and 3. The system has been successfully tested by the classification society DNV GL.

The Common Diesel Generator protection system (CDG protection) will be deployed for the first time on an offshore heavy lift vessel that is currently under construction. The ship is equipped with a power plant of four generators of 10 MW each, which run on both diesel and LNG. Generator protection is essential to prevent a blackout or failure in the power plant, causing the ship to lose its position during operations.

Vessels that sail in DP 2 or 3 mode have to maintain their position at all times, even in case of failures or malfunctions in the fuel system, a diesel, a generator, the switchboard, or the control system. To prevent such malfunctions, power plants are usually divided into independent isles. However, this makes generators run inefficiently, which is undesirable cost-wise and environmentally. That is why vessel operators now prefer generators in parallel operation.

To prevent these from interfering with each other, a generator safety system is necessary. Bakker Sliedrecht’s CDG protection system uses software to detect and disable an "unhealthy" generator before it can affect the "healthy" generators, making the entire power plant unstable. For power plants equipped with dual-fuel generators, this is more complex because dual-fuel engines behave differently than diesel engines and can unexpectedly switch from gas to diesel.

Without generator protection, a complex DP vessel will therefore not receive a certificate to operate in DP2 or DP3 closed bus mode. Bakker Sliedrecht started in 2017 with the further development of its own CDG protection system for complex work vessels. The system is now so far developed that it can be deployed in the heavy lift vessel. During the last months, it has been extensively tested in a setup of four generators.

According to DNV GL, the heavy lift vessel will be the first dual-fuel DP2 ship to be classified with a generator protection system.

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By Professional Mariner Staff