Roger Wiget

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This paper formulates a probabilistic securityconstraint optimal power flow considering a combination of an AC system and a multi-terminal HVDC grid that can depict the future power systems. The probabilistic formulation is discussed considering uncertainty in the generation infeed (e.g. wind power). To achieve a tractable problem we use a linearized(More)
In this paper, an optimal power flow for combined AC and DC grids is proposed. Several suggested projects to increase the transmission capacity are based on multi-terminal HVDC grids (MTDC). The construction of MTDC leads to major changes in the power flow of the existing grids. The problem description given in this paper considers the main points for power(More)
Many simulations in power systems analysis contain an AC grid which is solved using linearized power flow methods. This paper extends the known DC optimal power flow method for AC grids for use in combined AC and HVDC grids. Future studies would now incorporate in their simulations combined AC and HVDC grids. This paper describes the additions made to the(More)
This paper presents a decentralized controller for sharing primary AC frequency control reserves through a multi-terminal HVDC grid. By using passivity arguments, the proposed controller is shown to stabilize the equilibrium of the closed-loop system consisting of the interconnected AC and HVDC grids, given any positive controller gains. The static control(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)
This paper includes security constraints in OPF calculations for combined HVAC and HVDC grids. Two formulations of the problem are considered: a preventive and a corrective formulation. The outages of lines, generators and terminal stations are included. The preventive control method assumes that no control actions are taken after a contingency happens,(More)
In this paper, we present distributed controllers for sharing primary and secondary frequency control reserves for asynchronous AC transmission systems, which are connected through a multi-terminal HVDC grid. By using passivity arguments, the equilibria of the closed-loop system are shown to be globally asymptotically stable. We quantify the static errors(More)
Quality of homoeopathic mother tinctures is assured by the definition of the starting material, the manufacturing process and the analytical characteristics described in the monograph. Traditionally analytical characterisation of the mother tincture comprises appearance, odour, identity, density and dry residue. According to annex I of directive 2001/83/EC(More)
  • Michiel Tavernier, Roger Wiget, Michiel Andres Tavernier
  • 2014
This semester thesis deals with the dynamic modelling of a Voltage Source Converter based High Voltage Direct Current (VSC HVDC) system. The objective of the work is to expand an existing dynamic model of a two-terminal VSC HVDC system. The new model has to be capable to incorporate multiterminal HVDC grids with a meshed topology. Different case studies(More)
In this paper we present three different algorithms for the placement of multi-terminal HVDC interconnections. The speciality is the quantitative incorporation of operational flexibility in the placement algorithms. The first algorithm tries to find the most economical placement, the second algorithm looks for the placement which yields the highest(More)
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