Introduction:?At long last, the premier dynamic positioning (DP) conference has returned.?After being cancelled by Covid in the two previous years, it was good to get back and see everyone.?With two previous false starts, the conference attendance was down, but should recover after the Covid unpredictability disappears.?This year’s conference was more intimate, with the tables laid out like a wedding rather than a classroom, and the food was amazing.?As usual, the organizers did a great job.
What have we missed??Quite a lot.?My previous article mentioned that there is a move to establish practical criteria for effectively redundant closed bus operation.?That was the first workshop session and was summarized as something along the line of “Open minds and closed buses.”?The second workshop session was evaluating a redundancy concept philosophy document.?This could be very valuable, if properly implemented, but that was the main concern.?As a very experienced, industry veteran said to me during the workshop report out during the conference lunch, “Oh, they’re trying that again.”?Joey Fisher was honored with the Howard Shatto award for his work.?This included the School of ROCK, which was present on day 2 (next article).
Day 1, Session 1 – Operability:
Unlocking DP Performances with Non-Linear Control (s = shortened title) – Sofien Kerkeni, D-ICE Engineering
- Sofien has been doing interesting work with DP control systems.?He makes his own, optimizes them differently than the off-the-shelf DP systems, installs them, and proves them in operation.?He reduced system settling time to a third or half with improved vessel modeling.?This is useful for stop and go operations, such as wind farms.
K-BOS - Achieving a 9s Emergency Disconnect (s) – Steve Angstmann, Kinetic Pressure Control
- Steve has a cool, fast acting, pyrotechnic, shear ram, which I think has been presented before.?It’s smaller, faster, more effective, and can be retrofitted into existing BOP stacks.?Reducing the shear time by 20 to 60s allows larger red watch circles and increases drilling up time, especially in shallower water.?9s to shear and seal is excellent.
Levering Simulations for Predictable Outcomes – Zackary Clark, Kongsberg Maritime
- Zackary looked at using simulations and dynamic analysis to optimize vessel performance, improve human performance, and establish operation limits (e.g. ASOG).?I liked that he proved the effectiveness of the limits to the crew by letting them see what happens when they are exceeded.
Day 1, Session 2 – Power 1:
Lessons from Closed Bus Power System Dynamic Simulation (s) – Artur Zbronski, DNV Consulting
- Simulating dynamic power systems, testing them, putting the updated parameters into the model, rerunning the simulations, and testing again if needed - someone’s closing the simulation loop.?Asymmetric loading and running large and small DGs together can cause pole slip during a short.?[Some PMSs fail load steps in these conditions.]?Poor ring main connections can cause negative sequence circulating currents [good designers are aware & add bus protections].?He’s simulated hundreds of potential faults, but was unfamiliar with blackout from high THD, despite the DP incidents.
Zero Volt Ride Through Testing (s) – Sarah Whiteford, OneStep Power Solutions
- Buses connected through transformers act differently than ones directly connected (field decay). For those ones, a two breaker test is recommended. I’m used to drives staying live for a couple seconds and had failed an FMEA for unrealistic short tests the week before, so I was concerned by the short test times being used. Tenths of a second assume that the PMS is effective at emergency load reduction and that the unmaintained offshore breakers trip quickly and reliably.?It's not always the case. Brownouts can be worse than super short blackouts, as they can last longer.
Energy Efficiency Offshore (s) – Luciana Suman Jardim, Marmec Engineering
- We as an industry are in trouble.?Everyone knows the work needs done, but targeted reductions in pollution, combined with increasing demand, will challenge this.?Good measurement is vital to achieving the goals.?Her paper took data collected in Brazil and compared proxies that estimated pollution measurement and the trends of those proxies.?She found IMCA proxy A was better.
Day 1, Session 3 – Competency:
DP Competency & CPD – John Flynn, Stena Drilling
- Unfortunately, John was sick.?John has demonstrated effective use of training in the past and it would have been a good presentation focused on continual professional development.
DPOs Aren’t Elevator Operators – Paul Kerr, Global Maritime
- If you’ve read my articles then you know what I said.?Long ago, DP was an industry with poor external systems that was propped up by the local professionalism of its workers.?The top-down systems have grown hugely, but degraded the local professionalism that is the foundation of good operation, and that has cost us.?The workers and their bottom-up professional culture are still key and this needs supported.
DP CPD, Lessons for 4 Years Data – Mat Bateman, Keelson Marine Assurance
- Mat compiled his data from thousands of tests and they showed what we feared.?Trained and certified people, who have gone through all the externally imposed hoops and been operating ships for years, have basic misunderstandings of DP.?Mat notes that continual training closes these gaps and the results last for a while and build.?He has the test results to prove it.
Day 1, Session 4 – Incidents & Analysis
Conditioning Monitoring & Incident Investigation (s) – Dairon Campos, OneStep Power Solutions
- Dairon proposes measuring things, so we can understand them.?This is heresy in the offshore, but standard operating procedure in other industries, where it is considered part of their competitive advantage.?His examples looked at a DG overspeed blackout, emissions monitoring, and power quality.?As a separate system, it is competing against PMS & VMS manufacturers & needs covered in the FMEA.
DP Event Reporting; How, Why & What – Richard Purser, IMCA
- The importance and use of incident data, its anonymity, and its trends.?These lessons are fed back into IMCA guidance and training (CPD App).?Things are getting worse from 2019, humans are a major problem, and continuous professional development is recommended.?It looks like we have a theme.?We see few of the incidents that actually occur and need to support this service.?I fumbled a question.
Offloading using a Cargo Transfer Vessel (s) – Petter Stuberg, Kongsberg Maritime
- A CTV acts as an offloading interface between a Floating Production, Storage, and Offloading (FPSO) and tankers of opportunity.?It allows normal tankers to be used with reduced risk and eliminates the cost of intermediate shuttle tankers.?This was simulated, basin tested, further analyzed and adjusted, crew trained, and successfully proven at sea.?The CTV, and a tug, contain everything needed.
Conclusion:?This gives an overview of the first day and its theme – power redundancy, continual professional development, and the importance of good data and modeling.?This is only a brief summary of the official program.?If you were there then you already know everything, but my own comments.?If you weren’t there, then you missed out on the unofficial lessons, as well as the details only hinted at in these personal impressions.?MTS normally releases the papers and presentations after a year.
See the 2022 MTS DP Conference Program for more details.
Engineering Management Professional | Experienced, Practical, Registered Professional Engineer | Dynamic Positioning Subject Matter Expert (DP SME)
2 年Speaking of fumbling, I feel bad about using Sarah’s excellent presentation, which had good measurements from a good test setup and demonstrated the voltage decay problem clearly, as a stepping point to express concerns about modern designers’ unrealistically brief voltage dip ride-through survival times.?I used to test similarly.?Before the closed/open bus wars turned hot, experienced engineers would work with vendors to get a few seconds of blackout survival.?It's an important issue but is probably the topic for a separate article.
Technical Advisor Marine at IMCA (International Marine Contractors Association)
2 年Keep up the fumbling Paul