Line Roald

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Due to the increasing amount of electricity generated from renewable sources, uncertainty in power system operation will grow. This has implications for tools such as Optimal Power Flow (OPF), an optimization problem widely used in power system operations and planning, which should be adjusted to account for this uncertainty. One way to handle the(More)
This paper presents a variety of different Security Constrained Optimal Power Flow formulations addressing four power system operation and planning problems: (a) forecast uncertainty of Renewable Energy Sources (RES) in-feed and load, (b) security criteria based on contingency risk, (c) corrective control offered through High Voltage Direct Current (HVDC)(More)
Higher penetration of renewable energy and market liberalization increase both the need for transmission capacity and the uncertainty in power system operation. New methods for power system operational planning are needed to allow for efficient use of the grid, while maintaining security and robustness against disturbances. In this paper, we propose a risk(More)
As renewable wind energy penetration rates continue to increase, one of the major challenges facing grid operators is the question of how to control transmission grids in a reliable and a cost-efficient manner. The stochastic nature of wind forces an alteration of traditional methods for solving day-ahead and look-ahead unit commitment and dispatch. In(More)
Over the past years, the share of electricity production from wind power plants has increased to significant levels in several power systems across Europe and the United States. In order to cope with the fluctuating and partially unpredictable nature of renewable energy sources, transmission system operators (TSOs) have responded by increasing their reserve(More)
Higher penetration of fluctuating renewable energy sources (RES) and market liberalization increase both the demand for transmission capacity and the focus on cost efficient operation of the grid. To find a better trade-off between system security and the cost of operation, we propose to use a risk-based approach to system security. Risk-based security(More)
Authors are encouraged to submit new papers to INFORMS journals by means of a style file template, which includes the journal title. However, use of a template does not certify that the paper has been accepted for publication in the named journal. INFORMS journal templates are for the exclusive purpose of submitting to an INFORMS journal and should not be(More)
Offshore winds are generally stronger and more consistent than winds on land, making the offshore environment attractive for wind energy development. A large part of the offshore wind resource is however located in deep water, where floating turbines are the only economical way of harvesting the energy. The design of offshore floating wind turbines relies(More)