• Advanced model-based control of B36:45 LNG engines based on data driven models using machine learning tools 

      Kvåle, Svein Roar (Master thesis, 2021)
      This work is about developing a data driven MPC control for optimization of fuel consumption by minimizing the heat rate of an LNG gas engine from Bergen Engines AS. The model is based on real life data from an installed ...
    • Comparison of control strategies for a 2 DOF helicopter 

      Sharma, Roshan; Pfeiffer, Carlos Fernando (Journal article; Peer reviewed, 2017)
      The two degrees of freedom (2-DOF) helicopter is an openloop unstable multi-variable process. Various control strategies can be applied to stabilize the system for tracking and regulation problems but not all control methods ...
    • Covering the Gap Between Advanced Control Theory Design and Real Time Implementation Using Simulink 

      Pfeiffer, Carlos Fernando; Sharma, Roshan (Journal article; Peer reviewed, 2017)
      New developments in sensor technology and control actuators make it viable to monitor and regulate more process variables, providing an opportunity to apply advanced multivariable control techniques. Although modern control ...
    • Enhanced Power Capability of Generator Units for Increased Operational Security using NMPC 

      Øyvang, Thomas; Nøland, Jonas Kristiansen; Sharma, Roshan; Hegglid, Gunne John; Lie, Bernt (Peer reviewed; Journal article, 2019)
      The ever-increasing penetration of intermittent energy sources introduces new demanding operating regimes for the bulk power generation in the power grid. During a worst-case power system disturbance scenario, the generator ...
    • Flood Management of Lake Toke: MPC Operation under Uncertainty 

      Menchacatorre, Itsaso; Sharma, Roshan; Furenes, Beathe; Lie, Bernt (Peer reviewed; Journal article, 2019)
      A deterministic reference tracking model predictive control (MPC) is in use at Skagerak Kraft for flood management of Lake Toke in Norway. An operational inflow estimate is used to predict the optimal gate opening at Dalsfos ...
    • Formulation of Stochastic MPC to Balance Intermittent Solar Power with Hydro Power in Microgrid 

      Pandey, Madhusudhan; Winkler, Dietmar; Sharma, Roshan; Lie, Bernt (Peer reviewed; Journal article, 2021)
      In a microgrid with both intermittent and dispatchable generation, the intermittency caused by sources such as solar power and wind power can be balanced using dispatchable sources like hydro power. Both generation and ...
    • Model based control for run-of-river system. Part 1: Model implementation and tuning 

      Vytvytskyi, Liubomyr; Sharma, Roshan; Lie, Bernt (Journal article; Peer reviewed, 2015)
      Optimal operation and control of a run-of-river hydro power plant depends on good knowledge of the elements of the plant in the form of models. River reaches are often considered shallow channels with free surfaces. A ...
    • Model based control for run-of-river system. Part 2: Comparison of control structures 

      Vytvytskyi, Liubomyr; Sharma, Roshan; Lie, Bernt (Journal article; Peer reviewed, 2015)
      Optimal operation and control of a run-of-river hydro power plant depend on good knowledge of the elements of the plant in the form of models. Both the control architecture of the system, i.e. the choice of inputs and ...
    • Model Based Early Kick/Loss Detection and Attenuation with Topside Sensing in Managed Pressure Drilling 

      Jinasena, Asanthi; Holta, Haavard H. F.; Jondahl, Morten Hansen; Welahettige, Prasanna Kumara Welahetti; Aamo, Ole Morten; Sharma, Roshan; Viumdal, Håkon; Lie, Bernt (Peer reviewed; Journal article, 2020)
      Early kick/loss detection is a crucial part of safe well control, and it plays a major role in the reduction of risk and non-productive time in drilling. In conventional drilling, topside sensing is used for early kick/loss ...
    • Model based flow measurement using venturi umes for return flow during drilling 

      Pirir, Ivan; Jinasena, Asanthi; Sharma, Roshan (Journal article; Peer reviewed, 2017)
      In an oil well drilling operation, a proper knowledge of the return fluid flowrate is necessary both for the stabilization of the bottom hole pressure of the well and also as a primary indication of a kick or loss. In ...
    • Modeling and Analysis of Fluid Flow through A Non-Prismatic Open Channel with Application to Drilling 

      Jinasena, Asanthi; Ghaderi, Ali; Sharma, Roshan (Journal article; Peer reviewed, 2018)
      This paper presents the development and validation of a simplified dynamic model of a Venturi channel. The existing dynamic models on open channels are based on the open channel flow principles, which are the shallow water ...
    • Modeling and Simulation of Triclosan Kinetics and Distribution in Humans Using a PBPK Model 

      Maharjan, Samee; Sharma, Roshan; Husøy, Trine; Dirven, Hubert; Andreassen, Monica; Lie, Bernt (Conference object; Peer reviewed, 2015-11-25)
      Personal care products (PCPs) such as soaps, perfumes, toothpastes, lotions, etc. contain various chemicals. Triclosan (TCS) is widely used as an antibacterial additive in PCPs. Traces of TCS are found in human plasma and ...
    • Modeling for control of run-of-river power plant Grønvollsfoss 

      Vytvytskyi, Liubomyr; Sharma, Roshan; Granstrøm, Ingunn; Lie, Bernt (Conference object; Peer reviewed, 2015-11-25)
      Design of optimal operation and control of a run-of-river hydro power plant depends on good models for the elements of the plant. River reaches are often considered to be shallow channels with free surface flow. A typical ...
    • MPC Operation with Improved Optimal Control Problem at Dalsfoss Power Plant 

      Jeong, Changun; Furenes, Beathe; Sharma, Roshan (Peer reviewed; Journal article, 2021)
      The operational conditions at the Dalsfoss power station are complicated due to many requirements such as environmental regulations and safety constraints. Model predictive control (MPC) has been in use at this power station ...
    • Nonlinear observer for hydropower system 

      Vytvytskyi, Liubomyr; Sharma, Roshan; Lie, Bernt (Peer reviewed; Journal article, 2019)
      Estimation of unmeasured states plays an essential role in the design of control systems as well as for monitoring of hydropower plants. The standard Kalman filter gives the optimum state estimates for linear systems. ...
    • Optimal control strategies with nonlinear optimization for an Electric Submersible Pump lifted oil field 

      Sharma, Roshan; Glemmestad, Bjørn (Journal article; Peer reviewed, 2013)
      In an Electric Submersible Pump (ESP) lifted oil field, the ESP of each oil well should be operated inside its operating window. The total power consumed by the ESPs in the oil field should be minimized. The speed of the ...
    • Optimal Operation of Processes Under Uncertainty Using Robust Model Predictive Control 

      Jayamanne, Kushila Rasanduni (Master thesis, 2021)
      Model Predictive Control (MPC) is a well-established technology for advanced control of many industrial processes. One of its main benefits is the ability to handle process constraints. However, accuracy of the process ...
    • Optimal Operation of the Peat Drying Process in Steam Tube Dryers 

      Kulakovsky, Leonid; Rosen, Victor; Sharma, Roshan; Pfeiffer, Carlos Fernando; Lie, Bernt (Conference object; Peer reviewed, 2015-11-25)
      Ukraine is an energy-dependent country and aims to reduce the import of natural gas, heat, and power in general. This implies extracting fuel from her own natural resources; one relevant and readily available energy carrier ...
    • Optimization of lift gas allocation in a gas lifted oil field as non-linear optimization problem. 

      Sharma, Roshan; Fjalestad, Kjetil; Glemmestad, Bjørn (Journal article; Peer reviewed, 2012)
      Proper allocation and distribution of lift gas is necessary for maximizing total oil production from a field with gas lifted oil wells. When the supply of the lift gas is limited, the total available gas should be optimally ...
    • Parameter estimation for externally simulated thermal network models 

      Brastein, Ole Magnus; Lie, Bernt; Sharma, Roshan; Skeie, Nils-Olav (Peer reviewed; Journal article, 2019)
      Obtaining accurate dynamic models of building thermal behaviour requires a statistically solid foundation for estimating unknown parameters. This is especially important for thermal network grey-box models, since all their ...