Restoring the reliability of a deep-sea mining vessel by eliminating harmonic distortion

“Together with Merus Power, we were able to provide our customer with a reliable and effective solution, in a record delivery time.” – Jeremy Wood – Director of RWW Engineering

Challenges in the customer’s deep-sea mining vessel

The Debmar Atlantic vessel in Namibia underwent various modifications to be able to perform deep-sea mining. In the process, compressors and motors were installed fed by Variable Frequency Drives (VFD). The ship operates on an island grid with power generation of 11.7MW, 600V in 60Hz.

Because of the large number of VFDs, a harmonic distortion study was performed on the ship. Voltage harmonics as high as 12% under mining operations were discovered. Especially high were the 3rd- and 5th-order harmonics. The vessel follows the American Bureau of Shipping (ABS) standard, which allows only 5% of voltage harmonic distortion. Harmonics were causing problems such as tripping of circuit breakers, overheating of equipment, and compromised equipment lifetime and reliability.

Our Merus^® Solution

De Beers mining company decided to ensure the reliability of its operations by acquiring a Merus^® M500 Active Harmonic Filtering system and installing it to the vessel’s main switchboard. The contract was accomplished in cooperation with Merus Power’s South African partner RWW Engineering.

Key criteria in supplier selection were excellent performance and fast delivery time. Merus^® M-series Active Harmonic Filters are built on advanced technology and provide excellent performance for both even and odd harmonics.

Merus Power was able to prove the solution in an extremely tight schedule of 3 weeks. The vessel was at port for a limited time only, so the commissioning had to be done the next time it was at Cape Town port.

Results after installation

The Merus^® Active Harmonic Filter was successfully commissioned by RWW Engineering and Merus Power’s engineers, during the short window of time the vessel was at port. The primary objective to limit voltage harmonics under the 5% limit set by ABS was successfully met thanks to Merus Power’s solution. The performance was above the expectations of the end customer. The Debmar Atlantic mining vessel is not only able to operate reliably without interruptions but also increase the lifetime of its equipment to match that of its vessel, built in 1978.