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Baumann R.,Swissgrid | Eggenberger K.,E Bridge Consulting | Klaar D.,TenneT TSO bv | Obert O.,E Bridge Consulting | And 3 more authors.
CIGRE International Symposium Recife 2011 on Assessing and Improving Power System Security, Reliability and Performance in Light of Changing Energy Sources | Year: 2011

A group of fourteen TSOs1 in Central and Eastern Europe have set up a permanent TSO Security Panel and implemented a common IT Platform for data exchange and performing common security assessments (so called "CTDS"). The TSOs agree to improve system security by a more intensive cooperation, to develop common security assessment criteria and to grant an open data exchange (see website [1] and [2]). The CTDS System is in use in the control centres of the participating TSOs. The decision support by the CTDS System is fully integrated into daily operations. Each TSO can and does perform their own analyses, thus there is no need to take on trust externally provided, blackbox results. The individual views of the grid have been superseded by a common view. Therefore the CTDS System has greatly improved the quality of cooperation between control centres. Every operational planning engineer can replicate results distributed by every other operational planning engineer, the "Common language" speeds up joint problem-solving and decision-making. The CTDS System allows operators to confirm and compare effectiveness of different remedial actions. In principle, it is possible to determine the minimum cost for solving a given problem. These explicit optimisation functions are being added in future releases. One risk is that in an interconnected power system a remedial action activated by one TSO may solve one problem but create a new problem for another TSO. The cooperation process and the CTDS System keep this from happening by taking into account all side effects of a remedial action elsewhere in the system. It is also possible now to confirm that it may be more efficient if the neighbours solve the problem on behalf of a third TSO. The CTDS System makes it possible to replace less efficient unilateral or bilateral remedial actions with multilateral ones. The CTDS System determines technical efficiencies for remedial actions that benefit the entire regiońs security and should be applied on a regular basis as soon as possible. The cost determination principles of remedial actions, which are to be shared among TSOs are not defined yet because of the missing regulatory framework. Therefore applying the (cross border) remedial actions is not explicitly covered by the regulatory regimes. In the mid-term, a global solution for the allocation of common redispatch costs among TSC members will be necessary. The current diversity of national regulations requires strong commitment and support by the NRAs in order to find a suitable cost sharing principle. With the use of the CTDS System and the implementation of Real-Time Awareness & Alarm system (RAAS) for Central Europe the TSOs' common security assessment and decision making process on relieving security violations on a regional level will be improved. Furthermore ENTSO-E is working on a European-wide Awareness System (EAS) for realtime information and data exchange of critical grid parameters like frequency, Area Control Error (ACE) as well as a Traffic Light System which indicates the stress level of the European TSOs using a green, yellow or red light. The paper outlines the implementation process of the common IT-platform and the experiences of the coordination process of the TSOs. In addition to the technical aspects the economic and regulatory aspects are described. Furthermore an outlook towards the future developments of the TSO Security Cooperation (TSC) project is described. Source


Herrmann H.-J.,Siemens AG | Kuhn H.,Transpower | Fohring H.,Amprion | Ludwig A.,50Hertz Transmission GmbH | And 2 more authors.
43rd International Conference on Large High Voltage Electric Systems 2010, CIGRE 2010 | Year: 2010

This paper addresses the requirements of renewable generation in terms of protection concepts and also covers technical solutions surrounding disconnection of cogeneration plants. The German practice is introduced. Three guidelines exist as general rules. These describe the required boundary conditions. The first guideline addresses the general rules for connection of generation on the transmission network. The second addresses the connection conditions for infeed in medium voltage and the third for infeed in high voltage networks. The main renewable energy resource in Germany is wind, where the installed capacity reaches approximately 25 GW. The size of wind farms comes close to that of large power plant units being some hundred megawatts. Therefore this paper focuses on new challenges with renewable generation via wind farms. Due to the large installed power base, the dynamic behavior of such systems becomes very important. The following requirements must be fulfilled: - No immediate disconnection of the generation in the case of a network fault (coordinated disconnection is necessary) - Supporting of the line voltage during the fault via supply of reactive power - After fault clearing the consumption of reactive power must be the same as before. The generation must contribute the voltage stability by delivering reactive power. - One important rule is that the generation must remain connected for at least 150 ms to the system during voltage dips (fault-ride-through). The renewable generation must contribute to the fault clearing by delivering a short circuit current. The amount depends on the generation principle. Squirrel cage induction and double fed induction generators (DFIG) can deliver a fault current equal to a multiple of the rated current while via full converter design the short circuit current is smaller (close to the rated current). In typical examples the required technical solutions of the protection and disconnection concepts will be explained. The disconnection criteria are graded under- and overvoltage functions on the different voltage levels as well as over- and underfrequency functions based on typical frequency limits (f<: 47.5 Hz; f>: 51.5 Hz). Source


Patent
Board Of Regents Of The University Of Texas System and Amprion | Date: 2015-09-11

Methods and kits are provided for amplifying and detecting A proteins from samples, for example, from patients having Alzheimers Disease. For example, a method for determining a presence of a soluble, misfolded A protein may include contacting the sample with a monomeric, folded A protein to form an incubation mixture; conducting an incubation cycle two or more times on the incubation mixture effective to form an amplified portion of misfolded A protein; incubating the incubation mixture effective to cause misfolding and/or aggregation of at least a portion of the monomeric, folded A protein; physically disrupting the incubation mixture effective to at least partly de-aggregate at least a portion of a misfolded A aggregate present; and determining the presence of the soluble, misfolded A protein in the sample by detecting at least a portion of the amplified portion of misfolded A protein.


Patent
Board Of Regents Of The University Of Texas System and Amprion | Date: 2015-09-11

Methods and kits are provided for amplifying and detecting S proteins from samples, for example, from patients having Parkinsons Disease. For example, a method for determining a presence of a soluble, misfolded S protein may include: contacting the sample with a monomeric, folded S protein to form an incubation mixture; conducting an incubation cycle two or more times on the incubation mixture effective to form an amplified portion of misfolded S protein; incubating the incubation mixture effective to cause misfolding and/or aggregation of at least a portion of the monomeric, folded S protein in the presence of the soluble, misfolded S protein; physically disrupting the incubation mixture effective to at least partly de-aggregate at least a portion of a misfolded S aggregate present; and determining the presence of the soluble, misfolded S protein in the sample by detecting at least a portion of the soluble, misfolded S protein.


Patent
Board Of Regents Of The University Of Texas System and Amprion | Date: 2015-09-11

Methods and kits are provided for amplifying and detecting misfolded proteins from samples, for example, from patients having Alzheimers Disease, Parkinsons Disease, and the like. For example, a method for determining a presence of soluble, misfolded protein in a sample may include contacting the sample with a monomeric, folded protein to form an incubation mixture; conducting an incubation cycle two or more times effective to form an amplified portion of misfolded protein; incubating the incubation mixture effective to cause misfolding and/or aggregation of at least a portion of the monomeric, folded protein; physically disrupting the incubation mixture effective to break up at least a portion of any protein aggregate present; and determining the presence of the soluble, misfolded protein in the sample by detecting at least a portion of the soluble, misfolded protein. The monomeric, folded protein and the soluble, misfolded protein may exclude prion protein (PrP) and isoforms thereof.

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