This paper highlights how flexible and innovative engineering can replace electrical systems in existing and producing offshore facilities achieving minimized losses of production. It shows the opportunities realizing a major electrical infrastructure project on an offshore platform within a short timeframe and limited human resources. The fact that intelligent and simple solutions connecting a new offshore module into the existing infrastructure cut down the expected three weeks of production downtime to only four hours for each individual Electrical Submersible Pump System (ESP system). The main aim of this project was to avoid any shutdown of the production due to long installation phase for new equipment and decommissioning phase for the existing equipment. The whole project was split into well sized work-packages and interfaces to the existing infrastructure were considered.
Given the restricted space at Mittelplate, a new compact modular containerized solution was found allowing to set up offshore switchgear containers prior to removal of existing and operating ESP system. To avoid negative consequences during offshore installation and commissioning, tests of the entire simulation packages were completely run onshore. Based on lessons learned and training effects gained, several teams were able to reconnect 16 ESP without any downtime. Specially designed adapters allowed to directly connect the new Variable Speed Drive (VSD) to the existing Distributed Control System (DCS) without any production downtime. In parallel to onshore component tests, the project team started preparatory work on Mittelplate platform. One team focused on the installation of adapters, the second team was responsible for adaptation of the process graphics to the DCS. At the same time, the third team was busy installing and connecting the new power cables between variable speed drive system and step up transformer. After notice of completion given by all teams, system tests and commissioning were carried out together with the operator well by well.
Due to parallel work of three teams the wells could be successfully reconnected within unprecedented four hours average each. Furthermore, the whole work was carried out without any Lost Time Incident (LTI).