Browsing NTNU Open by Author "Imsland, Lars Struen"
Now showing items 21-40 of 80
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Coordinated Control of Multiple HVDC links using backstepping
Ersdal, Anne Mai; Imsland, Lars Struen; Uhlen, Kjetil (Journal article, 2012)This article regards a power system containing multiple High Voltage Direct Current (HVDC) links. The topic is to exploit the HVDC lines’ ability to control the power supplied by them to increase the stability of the system. ... -
Data-driven degradation model for batch processes: a case study on heat exchanger fouling
Wu, Ouyang; Bouaswaig, Ala; Schneider, Stefan; Leira, Fernando; Imsland, Lars Struen; Roth, Matthias (Journal article; Peer reviewed, 2018) -
Design and Experimental Validation of Nonlinear Infinite-Dimensional Adaptive Observer in Automated Managed Pressure Drilling
Hasan, Agus Ismail; Imsland, Lars Struen; Hauge, Espen (Journal article; Peer reviewed, 2017)Utilizing flow rate and pressure data in and out of the fluid circulation loop provides a driller with real-time trends for early detection of well-control problems that impact the drilling efficiency. Due to limited number ... -
Design and Implementation of a Simulation System for Vertical and Directional Drilling in an Autonomous Miniature Drilling Rig
Sundseth, Mads; Tjåland, Tor Arne (Master thesis, 2020)Digitalisering og automatisering av prosesser har i flere bransjer hatt stor påvirkning, særlig over de siste årene. Selv om R&D har utviklet en rekke før manuelle prosesser til å nå bli autonome, gjelder dette fortsatt ... -
Design and Implementation of a Simulation System for Vertical and Directional Drilling in an Autonomous Miniature Drilling Rig
Tjåland, Tor Arne; Sundseth, Mads (Master thesis, 2020)Digitalisering og automatisering av prosesser har i flere bransjer hatt stor påvirkning, særlig over de siste årene. Selv om R&D har utviklet en rekke før manuelle prosesser til å nå bli autonome, gjelder dette fortsatt ... -
Developing a Hybrid Data-Driven, Mechanistic Virtual Flow Meter - a Case Study
Hotvedt, Mathilde; Grimstad, Bjarne Andre; Imsland, Lars Struen (Peer reviewed; Journal article, 2021)Virtual flow meters, mathematical models predicting production flow rates in petroleum assets, are useful aids in production monitoring and optimization. Mechanistic models based on first-principles are most common, however, ... -
Distributed learning for wind farm optimization with Gaussian processes
Andersson, Leif Erik; Bradford, Eric; Imsland, Lars Struen (Journal article; Peer reviewed, 2020) -
Drillstring Washout Diagnosis using Friction Estimation and Statistical Change Detection
Willersrud, Anders; Blanke, Mogens; Imsland, Lars Struen; Pavlov, Alexey K. (Journal article; Peer reviewed, 2015)In oil and gas drilling, corrosion or tensile stress can give small holes in the drillstring, which can cause leakage and prevent sufficient flow of drilling fluid. If such \emph{washout} remains undetected and develops, ... -
Dynamic Real-Time Optimisation of a CO2 Capture Facility
Hotvedt, Mathilde; Hauger, Svein Olav; Gjertsen, Fredrik; Imsland, Lars Struen (Journal article; Peer reviewed, 2019)This work investigates economic optimisation of an energy-intensive amine regeneration process in a post-combustion CO2 capture plant, subject to a minimum CO2 capture ratio over 24 hours. A Dynamic Real-Time Optimisation ... -
Early pack-off diagnosis in drilling using an adaptive observer and statistical change detection
Willersrud, Anders; Imsland, Lars Struen; Blanke, Mogens (Journal article, 2015)Pack-off is a partially or complete blocking of the circulation flow in oil and gas drilling, which can lead to costly delays. Early detection and localization of a pack-off is crucial in order to take necessary actions ... -
Echo State Networks for Virtual Flow Metering in Gravity Separator
Vonen, Sivert (Master thesis, 2019)Virtuell volumstrøm estimering (Virtual Flow Metering, VFM), er et begrep som innebærer å estimere volumraten for de ulike fasene i en fler-fase volumstrøm uten å måle de direkte. Istedenfor så brukes data som er relatert ... -
Economic Stochastic Model Predictive Control Using the Unscented Kalman Filter
Bradford, Eric; Imsland, Lars Struen (Journal article; Peer reviewed, 2018)Economic model predictive control is a popular method to maximize the efficiency of a dynamic system. Often, however, uncertainties are present, which can lead to lower performance and constraint violations. In this paper, ... -
Economic stochastic nonlinear model predictive control of a semi-batch polymerization reaction
Bradford, Eric; Imsland, Lars Struen (Journal article; Peer reviewed, 2019)Batch processes are ubiquitous in the chemical industry and difficult to control, such that nonlinear model predictive control is one of the few promising control techniques. Many chemical process models however are affected ... -
Efficient optimization in Model Predictive Control
Ringset, Ruben Køste (Master thesis, 2009)Adjoint based gradient calculation for Nonlinear Model Predictive Control. -
Embedded Model Predictive Control on a PLC Using a Primal-DualFirst-Order Method for a Subsea Separation Process
Kufoalor, Kwame Minde; Richter, S; Imsland, Lars Struen; Johansen, Tor Arne; Morari, Manfred; Eikrem, Gisle Otto (Conference object; Journal article; Peer reviewed, 2014)The results of a PLC implementation of embedded Model Predictive Control (MPC) for an industrial problem are presented in this paper. The embedded MPC developed is based on the linear MPC module in SEPTIC (Statoil Estimation ... -
Expectation constrained stochastic nonlinear model predictive control of a batch bioreactor
Bradford, Eric Christopher; Imsland, Lars Struen (Chapter, 2017)Nonlinear model predictive control is a popular control approach for highly nonlinear and unsteady state processes, which however can fail due to unaccounted uncertainties. This paper proposes to apply a sample-average ... -
Fault diagnosis of downhole drilling incidents using adaptive observers and statistical change detection
Willersrud, Anders; Blanke, Mogens; Imsland, Lars Struen; Pavlov, Alexey (Journal article; Peer reviewed, 2015)Downhole abnormal incidents during oil and gas drilling cause costly delays, and may also potentially lead to dangerous scenarios. Different incidents will cause changes to different parts of the physics of the process. ... -
Implementation of a Miniature Autonomous Directional Drilling Rig With Nonlinear Model Predictive Trajectory Control
Steinstø, Magnus (Master thesis, 2021)Petroleumsindustrien har interesse av økt automasjon for å forbedre sikkerhet, redusere kostnader og øke effektivitet. Full-autonome boreoperasjoner kan forbedre sikkerhet ved å redusere antall mennesker i nærheten av ... -
Improved predictions from measured disturbances in linear model predictive control
Binder, Benjamin Julian Tømte; Johansen, Tor Arne; Imsland, Lars Struen (Journal article; Peer reviewed, 2019)Measured disturbances are often included in model predictive control (MPC) formulations to obtain better predictions of the future behavior of the controlled system, and thus improve the control performance. In the prediction ... -
Incident detection and isolation in drilling using analytical redundancy relations
Willersrud, Anders; Blanke, Mogens; Imsland, Lars Struen (Journal article; Peer reviewed, 2015-08)Early diagnosis of incidents that could delay or endanger a drilling operation for oil or gas is essential to limit field development costs. Warnings about downhole incidents should come early enough to allow intervention ...