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  • 1.
    Andersson, Robert
    et al.
    University of Kalmar, Kalmar Maritime Academy.
    Huss, Karl
    University of Kalmar, Kalmar Maritime Academy.
    Lagerberg, Henrik
    University of Kalmar, Kalmar Maritime Academy.
    PLC-Baserat Maskinlarm ombord Ms Calmare Nyckel2009Independent thesis Basic level (professional degree), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    This graduate report describes the work relating to the development of a brand new monitoring and machinery alarm system onboard the training vessel M/S Calmare Nyckel. The system developed, is based on PLC automation technology, and allows graphical presentation of system data.

    The project was managed by three marine engineering students at the Kalmar Maritime Academy.

  • 2.
    Buttar, Sarpreet Singh
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Applying Artificial Neural Networks to Reduce the Adaptation Space in Self-Adaptive Systems: an exploratory work2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Self-adaptive systems have limited time to adjust their configurations whenever their adaptation goals, i.e., quality requirements, are violated due to some runtime uncertainties. Within the available time, they need to analyze their adaptation space, i.e., a set of configurations, to find the best adaptation option, i.e., configuration, that can achieve their adaptation goals. Existing formal analysis approaches find the best adaptation option by analyzing the entire adaptation space. However, exhaustive analysis requires time and resources and is therefore only efficient when the adaptation space is small. The size of the adaptation space is often in hundreds or thousands, which makes formal analysis approaches inefficient in large-scale self-adaptive systems. In this thesis, we tackle this problem by presenting an online learning approach that enables formal analysis approaches to analyze large adaptation spaces efficiently. The approach integrates with the standard feedback loop and reduces the adaptation space to a subset of adaptation options that are relevant to the current runtime uncertainties. The subset is then analyzed by the formal analysis approaches, which allows them to complete the analysis faster and efficiently within the available time. We evaluate our approach on two different instances of an Internet of Things application. The evaluation shows that our approach dramatically reduces the adaptation space and analysis time without compromising the adaptation goals.

  • 3.
    Chen, Boyang
    et al.
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Xu, Mingyi
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Design of a Quay Crane Training Simulator2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 4.
    Evegren, Adam
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Utveckling av återkopplad motormodul för styrning av mätantenn: En fallstudie hos företaget Combitech AB2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med föreliggande studie är att undersöka vilket motoralternativ som lämpar sig bäst för precis positionsstyrning av särskilda mätantenner, samt hur denna motor skall kunna drivas på ett funktionellt vis. Huvudresultatet som vill uppnås genom detta projekt är en generell motormodul kapabel att styra antennernas olika dimensioner utifrån användarens kommando genom seriell kommunikation från en PC. Studien har genomförts i samarbete med företaget Combitech AB.

  • 5.
    Fiaschetti, Andrea
    et al.
    University of Rome La Sapienza, Italy.
    Lavorato, Francesco
    University of Rome La Sapienza, Italy.
    Suraci, Vincenzo
    University of Rome La Sapienza, Italy.
    Palo, Andi
    University of Rome La Sapienza, Italy.
    Taglialatela, Andrea
    TRS SpA, Italy.
    Morgagni, Andrea
    Elsag Datamat S.p.a., Italy.
    Baldelli, Renato
    Elsag Datamat S.p.a., Italy.
    Flammini, Francesco
    Ansaldo STS S.p.a., Italy.
    On the use of semantic technologies to model and control security, privacy and dependability in complex systems2011In: Computer Safety, Reliability, and Security: 30th International Conference, SAFECOMP 2011, Naples, Italy, September 19-22, 2011, Proceedings / [ed] Francesco Flammini, Sandro Bologna, Valeria Vittorini, Berlin, Heidelberg: Springer, 2011, p. 467-479Conference paper (Refereed)
    Abstract [en]

    In this paper a semantic approach is presented to model and control Security, Privacy and Dependability (SPD) in complex interconnected environment composed by heterogeneous Embedded Systems. Usually, only the individual properties are locally considered to obtain desired functionalities and this could result in sub-optimal solutions. With the use of modern semantic technologies (like OWL or reasoning engines) it is possible to model not only the individual parameters but also the relations between the different (and dynamically changing) parts of the systems, thus providing enriched knowledge and more useful information that could feed control algorithms. The model presented in this paper is based on the results obtained during the first phase of the pSHIELD project (conceived and lead by Finmeccanica) and it is focused on a concrete application coming from a critical scenario in railway environment: the monitoring of freight trains transporting hazardous material.

  • 6.
    Hamon, Camille
    et al.
    Royal Institute of Technology.
    Perninge, Magnus
    Lund University.
    Söder, Lennart
    Royal Institute of Technology.
    Applying stochastic optimal power flow to power systems with large amounts of wind power nd detailed stability limits2016In: 2013 IREP Symposium Bulk Power System Dynamics and Control - IX Optimization, Security and Control of the Emerging Power Grid (IREP), IEEE Press, 2016Conference paper (Refereed)
    Abstract [en]

    Increasing wind power penetration levels bring about new challenges for power systems operation and planning, because wind power forecast errors increase the uncertainty faced by the different actors. One specific problem is generation re-dispatch during the operation period, a problem in which the system operator seeks the cheapest way of re-dispatching generators while maintaining an acceptable level of system security. Stochastic optimal power flows are re-dispatch algorithms which account for the uncertainty in the optimization problem itself. In this article, an existing stochastic optimal power flow (SOPF) formulation is extended to include the case of non-Gaussian distributed forecast errors. This is an important case when considering wind power, since it has been shown that wind power forecast errors are in general not normally distributed. Approximations are necessary for solving this SOPF formulation. The method is illustrated in a small power system in which the accuracy of these approximations is also assessed for different probability distributions of the load and wind power.

  • 7.
    Hamon, Camille
    et al.
    Royal Institute of Technology.
    Perninge, Magnus
    Royal Institute of Technology.
    Söder, Lennart
    Royal Institute of Technology.
    Stochastic optimal power flow problem with stability constraints2013In: 2013 IEEE Power and Energy Society General Meeting (PES), IEEE, 2013Conference paper (Refereed)
    Abstract [en]

    Summary form only given. Stochastic optimal power flow can provide the system operator with adequate strategies for controlling the power flow to maintain secure operation under stochastic parameter variations. One limitation of stochastic optimal power flow has been that only limits on line flows have been used as stability constraints. In many systems voltage stability and small-signal stability also play an important role in constraining the operation. In this article we aim to extend the stochastic optimal power flow problem to include constraints for voltage stability as well as small-signal stability. This is done by approximating the voltage stability and small-signal stability constraint boundaries with second order approximations in parameter space. Then we refine methods from mathematical finance to be able to estimate the probability of violating the constraints. In the first part of the article, we derive second-order approximations of stability boundaries in parameter space. In the second part of the article, we look at how Cornish-Fisher expansion combined with a method of excluding sets that are counted twice, can be used to estimate the probability of violating the stability constraints. We then show in a numerical example how this leads to an efficient solution method for the stochastic optimal power flow problem.

  • 8.
    Hultgren, Anders
    et al.
    Blekinge Tekniska Högskola.
    Melin, Jan
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Ranstad, Per
    Alstom Power.
    Limit Cycles in an Industrially Applied Hybrid System2010In: 2010 11th International Workshop on 11th IEEE Workshop on Variable Structure Systems, Mexico City: IEEE Press, 2010, p. 277-282Conference paper (Refereed)
    Abstract [en]

    An Industrially applied LCC power converter is modelled as a hybrid system. It is found that the hybrid system with three continuous states and one logic state given a parameter set up and different initial conditions has among other solutions one central closed trajectory and two types of limit cycles, on the left and the right side. The other solutions are indicated.

  • 9.
    Ketelaars, Stefan
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering. Fontys.
    DC Motor driver for low RPM2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    For this project the main goal was to design, simulate, build and test a DC motor driver. To accomplish this four specific parts had to be design. First a DCDC converter that converts the input signal from an external power supply in a controllable DC output. The second part was a DCDC converter that converts the DC input in a voltage useful for the function generator, the third part is the function generator that provides a signal to the H-Bridge, and the final part is the H-Bridge itself. The goal is to compare the measurement with the simulations to the expectations. What we are interested in is the influence of EMF when the RPM of the motor is zero or close to zero.

  • 10.
    Kolbasi, Elif Ceylan
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Control of temperature using fuzzy system tehnique2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Fuzzy control is based on fuzzy logic. A logical system that is much closer in spirit to human thinking and natural language than traditional crisp logical systems. The fuzzy logic variables are not described as true or false values. Instead values range in degree between 0-1,true-false or yes-no. Fuzzy logic provides as a means of converting with linguistic control strategy.This strategy rules are based on expert knowledge that is invented by a plant operator or a design egineer. Especially the exposition includes a discussion of fuzzification and defuzzification strategies,the derivation of the database and fuzzy control rules,the definition of fuzzy implication and an analysis of fuzzy reasoning mechanisms. Fuzzy logic is used in machine control widely .Although genetic algoritms and neural networks can perform as well as fuzzy logic in many cases. In the other hand fuzzy logic has advantage that the solution of problem can be formalize terms in that human operators can understand easily so their experience can be used in the design of the controller. Fuzzy controller is generally nonlinear because it doesn’t have a simple equation like the PID ,but also PID control is not convenient in that case of higher-order plants.The fuzzy controllers appear in consumer products.For instance washing mashines,video cameras,underground trains and robots.A fuzzy controller acts or regulates by means of rules in a more or less natural language based on the distinguish feature: fuzzy logic.

  • 11.
    Larsson, Roger
    et al.
    University of Kalmar, Kalmar Maritime Academy.
    Borg, Martin
    University of Kalmar, Kalmar Maritime Academy.
    Nordh, Ulf
    University of Kalmar, Kalmar Maritime Academy.
    Digitalt maskinövervakningssystem för vedettbåt typ III Dalarö2008Independent thesis Advanced level (degree of Master), 5 poäng / 7,5 hpStudent thesis
    Abstract [en]

    This exam work was initiated by a request from Sjövärnskåren division Syd. They wanted to implement a newer, computer based system with graphical display, an engine monitoring system which was ment to provide the engineer on watch with data from the engines. The object for this is to reduce the maintenance costs through improved monitoring while running and to improve documentation which later on the maintenance measures is based on.

    The project was an initial study which conclusions and recommendations on systems suited for the task is to give Sjövärnskåren an economical frame.

    We met up in Karlskrona on the ship and had a discussion about which parameters that should be presented. After that we started to go through the documentation and perform onsite surveys to conclude what signals the transmitters put out to the existing monitoring system.

    This was a delicate task, information about the transmitters was lacking in the documentation.

    The onsite measures gave no vital information. We talked to the shipyards and maintenance units that the ship had been in contact with during its time in the navy. We came in contact with a man that had been working with this ship, and he gave us information that told us that the transmitters were of standard type, 4-20 mA.

    With this information, the project pursued and we invited tenders to give us systems that could cope with the task.

    We had three tenders thar supplied us with systems. All of theese meant considerable programmingwork to get the monitoring system up and running.

  • 12.
    MOULKI, Mohammad Firas
    et al.
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Khashab, Mohamad
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Haptic Servo System2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A ”Haptic servo system” is here understood as a servo system whereforces from a controlled system are fed back to an operator. This thesis workis a design work where the work among other things comprises the choice ofsuitable motors, one for operating the beam and another one for operatingthe steering wheel. Data for the beam and ball are assumed to be known.Data for the feed back torque to the steering wheel is assumed to be specifiedin advance. Two models to represent the human response are suggested. Asimulation study is carried out to show that the system works according tosome specification. The ball and beam process is simulated with hardwarein the loop. The hardware in the loop is a Maxon motor. The motor is usedas the steering wheel and the motor will also propagate the torque feedbackto the operator.The task of the thesis work could then be formulated as: Can a human, withtorque feedback, manually control the ball on the beam without looking atthe ball and the beam?

  • 13.
    Nilsson, Börje
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering.
    Nordebo, Sven
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering.
    Sjödén, Therese
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering.
    Estimation of Twist in Uniaxial Cylinders WithInverse Electromagnetic Scattering2009In: IEEE Transactions on Antennas and Propagation, ISSN 0018-926X, E-ISSN 1558-2221, Vol. 57, no 10, p. 3264-3273Article in journal (Refereed)
    Abstract [en]

    For the purpose of determining the twist of a homogeneous, locally reacting, uniaxial cylinder, an inverse microwave scattering theory is presented. Remote measurements of the spiral grain of trees and logs are the prime application. Based on practical considerations, it is assumed that the transmitting and receiving antennas are collocated, requiring a three-dimensional modelling. A general theory is first developed, followed by an asymptotic analysis assuming that the distance from the antennas to the cylinder is many wavelengths and many cylinder radii. In this way, a substantial reduction of the numerical complexity, to the level of the two-dimensional case, is achieved. The error of the determined twist angle as function of inherent parameters of the problem using a CramEacuter-Rao analysis is given. The results from numerical simulations show that this error is low enough for determining the grain angle. Presented parameter studies of the error can be used for minimizing the errors in a measurement set up, of particular interest for non-sophisticated instruments and non-ideal laboratory conditions, by selecting optimum parameters such as frequency and antenna gain. Finally, it is stated that the model has a great potential for developing efficient algorithms for measuring the twist angle.

  • 14.
    Olsen, Erik
    et al.
    University of Kalmar, Kalmar Maritime Academy.
    Larsson, Jens
    University of Kalmar, Kalmar Maritime Academy.
    Stjernström, Dennis
    University of Kalmar, Kalmar Maritime Academy.
    Nyinstallation av Larmsystem Till NOHAB-Diesel: Denna rapport innefattar förfarande från att konstruera och installera ett helt nytt larmsystem2009Independent thesis Basic level (professional degree), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    School ship M/S Calmare Nyckel, owned and operated by the Maritime University of Kalmar is used for training by both prospective merchant marine officer as well as engineers. The operation of NOHAB-diesel, used as a generator, has been problematic with frequent and unexplained stop. The alarm system installed by the Oskarshamn Shipyard was highly dysfunctional. The alarm system was dangerous to personnel when it was built on 230volt, furthermore were the alarm points constructed in series with only a stop indication. The lack of electrical drawings of the system made it impossible to trouble shot the deficiencies in the alarm system. Moreover, there was no alarm indication in the control room but only locally at the NOHAB-diesel.

     

    We have made a new installation of the alarm system with the higher personal safety 24VDC, with all the alarms parallel with the corresponding indication on the panel, both locally at the NOHAB-diesel and on the control table for good review of the system. Furthermore, we have made complete drawings of the system enabling a good overview and the ability to troubleshoot.In this report we describe the approach to the problem solutions that have emerged in the process of creating a functioning alarm system.

  • 15.
    Perninge, Magnus
    Lund University.
    A Control-variable Regression Monte Carlo Technique for Short-term Electricity Generation PlanningManuscript (preprint) (Other academic)
    Abstract [en]

    n the day-to-day operation of a power system, the system operator repeatedly solves short-termgeneration planning problems. When formulating these problems theoperators have to weigh the riskof costly failures against increased production costs. The resulting problems are often high-dimensionaland various approximations have been suggested in the literature.In this article we formulate the short-term planning problem as an optimal switching problem withdelayed reaction. Furthermore, we proposed a control variable technique that can be used in MonteCarlo regression to obtain a computationally efficient numerical algorithm.

  • 16.
    Perninge, Magnus
    Lund University.
    A Limited-Feedback Approximation Scheme for Optimal Switching Problems with Execution DelaysManuscript (preprint) (Other academic)
    Abstract [en]

    We consider a type of optimal switching problems with non-uniform execution delays and ramping.Such problems frequently occur in the operation of economical andengineering systems. We first pro-vide a solution to the problem by applying a probabilistic method. The main contribution is, however,a scheme for approximating the optimal control by limiting the information in the state-feedback.In a numerical example the approximation routine gives a considerable computational performanceenhancement, when compared to a conventional algorithm.

  • 17.
    Perninge, Magnus
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    A limited-feedback approximation scheme for optimal switching problems with execution delays2018In: Mathematical Methods of Operations Research, ISSN 1432-2994, E-ISSN 1432-5217, Vol. 87, no 3, p. 347-382Article in journal (Refereed)
    Abstract [en]

    We consider a type of optimal switching problems with non-uniform execution delays and ramping. Such problems frequently occur in the operation of economical and engineering systems. We first provide a solution to the problem by applying a probabilistic method. The main contribution is, however, a scheme for approximating the optimal control by limiting the information in the state-feedback. In a numerical example the approximation routine gives a considerable computational performance enhancement when compared to a conventional algorithm.

  • 18.
    Perninge, Magnus
    Lund University.
    Approximating the parameter-space stability boundary considering post-contingency corrective controls2015In: Electric power systems research, ISSN 0378-7796, E-ISSN 1873-2046, Vol. 121, p. 313-324Article in journal (Refereed)
    Abstract [en]

    Lately, much work in the area of voltage stability assessment has been focused on finding post-contingency corrective controls. In this article a contribution to this area will be presented where we investigate the surface of maximal loadability while allowing for post-contingency corrective controls. This objective is different from the usual, where the aim is to include the post-contingency controls in a security-constrained optimal power flow. Our aim is rather to find approximations of the post-contingency stability boundary, in pre-contingencyparameter space, while including the possibility for post-contingency corrective controls. These approximations can then be used in, for example, a chance-constrained optimal power flow routine.

  • 19.
    Perninge, Magnus
    Lund University.
    Stochastic optimal power flow by multi-variate Edgeworth expansions2014In: Electric power systems research, ISSN 0378-7796, E-ISSN 1873-2046, Vol. 109, p. 90-100Article in journal (Refereed)
    Abstract [en]

    Stochastic optimal power flow can provide the system operator with adequate strategies for controlling the power flow to maintain secure operation under stochastic parameter variations. One limitation of stochastic optimal power flow has been that only steady-state variable limits have been used as security constraints. In many systems voltage stability and small-signal stability also play an important role in constraining the operation. Recently an extension of the stochastic optimal power flow formulation that included constraints for voltage stability as well as small-signal stability was proposed. This was done by approximating the voltage stability and small-signal stability constraint boundaries with second order approximations in parameter space. In this article an alternative solution method to this problem will be proposed. The new improved solution method, which is based on Edgeworth series expansions, is both more efficient and accurate. We also give details on convexity of the problem and discuss some computational issues.

  • 20.
    Perninge, Magnus
    et al.
    Lund University.
    Eriksson, Robert
    Markets and System Development Swedish National Grid.
    A stochastic control formulation of the continuous-time power system operation problem2016In: 2016 IEEE 16th International Conference on Environment and Electrical Engineering (EEEIC), IEEE Press, 2016Conference paper (Refereed)
    Abstract [en]

    In this paper we show how to build an economically optimal feedback control strategy for the re-dispatch of electricity generation. We assume that the operator steers production in a set of controllable power plants by altering the active power set-point of each generator, within a set of predefined set-points. Theoperators strategy will be based on balancing the operating cost against the expected cost from unserved demand. Important aspects are ramp-rates at which production can approach the set-point, and switching costs arising from increased fuel consumption during ramping and wear and tear on production facilities.

  • 21.
    Perninge, Magnus
    et al.
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Eriksson, Robert
    Swedish National Grid.
    Frequency Control in Power Systems Based on a Regulating Market2018In: IEEE Transactions on Control Systems Technology, ISSN 1063-6536, E-ISSN 1558-0865, Vol. 26, no 1, p. 27-37Article in journal (Refereed)
    Abstract [en]

    In power systems, the system frequency is a good indicator of the networks resilience to major disturbances. In many deregulated markets, eg the Nordic power market, the system operator controls the system frequency manually by calling off bids handed in to a market, called the regulating market. In this paper, we formulate the problem of optimal bid call-off on the regulating market that the system operator is faced with each operating period, as an optimal starting problem with delays. As general optimal starting problems with delays are computationally cumbersome, we present two alternative approximation schemes. First, we make simplifications to the problem that renders classical solution concepts tractable; then, in a second approach, we define a suboptimal solution scheme, based on limiting the feedback information.

  • 22.
    Perninge, Magnus
    et al.
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Eriksson, Robert
    Swedish National Grid.
    Optimal Tertiary Frequency Control in Power Systems with Market-Based Regulation2017In: IFAC-PapersOnLine, Elsevier, 2017, Vol. 50, p. 4374-4381Conference paper (Refereed)
    Abstract [en]

    The system frequency of a power systems is a good indicator of the networks resilience to major disturbances. In a completely deregulated setting, for example in the Nordic power system, the system operator controls the system frequency manually by calling-off bids handed in to a market, called the regulating market.

    In this paper we formulate the problem of optimal bid call-off on the regulating market, that the system operator is faced with each operating period, as an optimal switching problem with execution delays.

    As general optimal switching problems with execution delays are computationally cumbersome we resort to a recently developed suboptimal solution scheme, based on limiting the feedback information in the control loop.

  • 23.
    Perninge, Magnus
    et al.
    KTH Royal Institute of Technology.
    Söder, Lennart
    KTH Royal Institute of Technology.
    A stochastic control approach to manage operational risk in power systems2012In: IEEE Transactions on Power Systems, ISSN 0885-8950, E-ISSN 1558-0679, Vol. 27, no 2, p. 1021-1031Article in journal (Refereed)
    Abstract [en]

    In this paper, the novel method operational risk managing optimal power flow (ORMOPF), for minimizing the expected cost of power system operation, is proposed. In contrast to previous research in the area, the proposed method does not use a security criterion. Instead the expected cost of operation includes expected costs of system failures.

  • 24.
    Perninge, Magnus
    et al.
    Lund University.
    Söder, Lennart
    Royal Institute of Technology.
    Irreversible investments with delayed reaction: an application to generation re-dispatch in power system operation2014In: Mathematical Methods of Operations Research, ISSN 1432-2994, E-ISSN 1432-5217, Vol. 79, no 3, p. 195-224Article in journal (Refereed)
    Abstract [en]

    In this article we consider how the operator of an electric power system should activate bids on the regulating power market in order to minimize the expected operation cost. Important characteristics of the problem are reaction times of actors on the regulating market and ramp-rates for production changes in power plants. Neglecting these will in general lead to major underestimation of the operation cost. Including reaction times and ramp-rates leads to an impulse control problem with delayed reaction. Two numerical schemes to solve this problem are proposed. The first scheme is based on the least-squares Monte Carlo method developed by Longstaff and Schwartz (Rev Financ Stud 14:113–148, 2001). The second scheme which turns out to be more efficient when solving problems with delays, is based on the regression Monte Carlo method developed by Tsitsiklis and van Roy (IEEE Trans Autom Control 44(10):1840–1851, 1999) and (IEEE Trans Neural Netw 12(4):694–703, 2001). The main contribution of the article is the idea of using stochastic control to find an optimal strategy for power system operation and the numerical solution schemes proposed to solve impulse control problems with delayed reaction.

  • 25.
    Perninge, Magnus
    et al.
    Royal Institute of Technology.
    Söder, Lennart
    Royal Institute of Technology.
    Optimal activation of regulating bids to handle bottlenecks in power system operation2012In: Electric power systems research, ISSN 0378-7796, E-ISSN 1873-2046, Vol. 83, no 1, p. 151-159Article in journal (Refereed)
    Abstract [en]

    In this article we investigate how to optimally activate regulating bids to handle bottlenecks in power system operation. This will lead to an optimal stopping problem, and activation of a regulating bid is to be performed when the transfer through a specific system bottleneck reaches a certain value. Compared to previous research in the area the work presented in this article includes a more detailed model of the structure of the regulating market, and reaction times of actors on the regulating market is taken into consideration. The emphasis of the presentation will be application to a two area test system. The method is compared to Monte Carlo simulation in a numerical example. The example shows a promising result for the suggested method.

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