Offshore oil rig, Baltic Sea

Industry: Oil & gas
Customer: Gazprom flot
Design & Implementation: IC ART
Rig name: Arkticheskaya, a jackup rig with a rated drilling depth of 21,500 ft.
Timeline: The project started June 15, 2016 and finished August 22, 2016.

Challenge: Reactive Power

Due to current limitations during operation, Arkticheskaya struggled with multiple harmonic disturbances and insufficient current, leaving Gazprom flot unable run the operation at full capacity.

Arkticheskaya’s poor PF (caused by uncompensated reactive power) meant that the rig’s two generators couldn’t cover the load of the main consumers. And while generally on a rig you want to run as few generators as possible (to minimize fuel consumption), Gazprom flot was forced to run Arkticheskaya’s extra generator to compensate for the insufficient current created by reactive power.

Contributing to the rig’s low PF were the eight on-board DC drives putting high demand on the grid.

When reactive power goes uncorrected, many experience grid instability, increased electrical costs, and limited transmission capacity.

While reactive power was a key issue for Arkticheskaya, the capacitors on the rig’s on-board passive filters exploded, leaving Gazprom flot in need of a new solution.

Hoist group results

Hoist group result 2

Solution

With the sensitive equipment on-board Arkticheskaya, Gazprom flot needed an active solution for better protection—which isn’t possible with a passive filter solution. So the first step was to detach the capacitors from the existing passive filters and commission an active filter solution.

16 x ADF P100 units

Due to their small size, the P100’s enabled quick installation—which was a top priority for the customer. ADF was also selected due to its proven track record in the business, quick delivery, good local service, and the compact size of the installation.

After installation, the local partner trained Arkticheskaya staff on the solution.

training trained Arkticheskaya staff on the solution

Result

Arkticheskaya’s new PF varies highly depending on the load, but the target was to reach PF of 0.8 at max load during stable drilling and the goal was reached.

In such a dynamic, demanding environment, passive filters are insufficient. The active compensation capabilities of the ADF P100’s compensate the rig’s reactive power and the harmonics produced by the DC drives.

Our customer reports they are satisfied with the solution, especially that the installation and commissioning was done in such a short amount of time.

Dynamic load = 1500 A rise in 5 seconds from the hoists (one of the loads)