By Hans De Keulenaer / Published on Wed, 2009-02-25 12:22
The Council of European Energy Regulators (CEER) just published its 4th Benchmarking Report on the Quality of Electricity Supply. It deals with three types of electricity quality: the speed and accuracy with which electricity customer requests are handled (commercial quality); the availability of electricity (continuity); and its technical properties (voltage quality).
Lord Mogg, CEER President, said, “In order to ensure that quality is not compromised as electricity companies seek to cut costs, more and more regulators have introduced electricity quality incentive/penalty regimes.”
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By Hans De Keulenaer / Published on Tue, 2008-05-06 14:33
Problems on inverter motor drives such as bearing currents are introduced due to common mode voltages. Different solutions are proposed on literature, for two-level or multilevel inverter. Instantaneous zero common mode voltage by using a three-level inverted could be achieved. This paper proposes a commutation strategy that allows zero common mode voltage by using medium vectors, and also a new representation as a plane on the commutation space is defined which is called zero common mode voltage plane. On this defined plane, every turning vector fulfil this property.
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By Hans De Keulenaer / Published on Tue, 2008-05-06 14:30
The electricity is a basic need for functioning of modern society. In the deregulated electricity market, delivering quality power to the clients is a challenge for the utilities. In this paper, a “hybrid grid” is discussed that consists of centralized generations and localized distributed generations which may be comprised of small-scale conventional and sustainable sources. Energy storage option is also integrated in the hybrid-grid. Simulations are done on a test network, using “Power-Factory” software.
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By Isabelle Heriakian / Published on Wed, 2008-04-09 16:39
Bart Franken & Erwin Hoeskma from Kema explain what regulators need to consider in establishing an effective voltage quality regulatory framework for distribution networks. In particular, they consider the regulation of five voltage quality dimensions: short interruptions, voltage dips, flicker, supply voltage variation, and harmonic distortions. Their work assesses the most appropriate regulatory control method and presents practical experiences through a number of case studies.
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By Bruno De Wachter / Published on Thu, 2008-03-20 17:06
A detailed analysis by the Technical Research Centre of Finland
One of the major drawbacks of wind energy is that it requires extra reserve capacity to compensate for the intermittency of its power output. Opponents of wind energy even contend that it requires a 100% back up: they claim each megawatt of wind power would require a megawatt from a combined cycle power plant as a standby. A study by the Technical Research Centre of Finland has now demonstrated this last claim to be incorrect.
Size matters
The study 'Design and operation of power systems with large amounts of wind power' was commissioned by the International Energy Agency (IEA) for its Wind Implementing Agreement, and resulted in a state-of-the-art report. It shows that the amount of back up needed for wind energy varies greatly according to the systems’ characteristics. The size of the system and the correlation of wind production with peak demand are two major and decisive factors.
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By HDK / Published on Mon, 2006-01-30 14:13
Date: February 24, 14h00 GMT+1
Duration: 1 hour
Speaker: Torbjorn Solver, Royal Institute of Technology in Stockholm
In re-regulated and restructured electricity markets the production and retail of electricity is conducted on competitive markets, the transmission and distribution on the other hand can be considered as natural monopolies. The financial regulation of Distribution System Operators (DSOs) has in many countries gone through a major switch in policy. From the traditional and often considered inefficient cost-based regulation towards a more complex environment of regulatory framework were the DSOs’ performance are value instead of their costs, ie performance-Based regulation (PBR). In PBR the direct link between cost and income is weakened or sometimes removed, which give the regulated DSOs strong cost cutting incentives and there is consequently a risk of system reliability deterioration due to action undertaken by the DSOs such as postponed maintenance and investments in order to save costs. To balance this risk the PBR-framework is normally complemented with some kind of quality regulation. How both the PBR frameworks as well as the framework for regulation of quality are constructed determines the incentive that the DSO will act on and will therefore influence the system reliability development.
This thesis links the distribution system reliability to performance-based regulatory regimes. This is conducted by first identify the key incentive features within PBR, and second, quantify the findings by subjecting a test system to various general PBR frameworks and conduct Monte Carlo Simulations of the system reliability. The MCS enables detailed analysis of regulatory features, parameter settings and financial risk assessments. In addition, the applied PBR-frameworks can be quantitatively compared. Finally, some focus have been put on the Swedish regulation and the tool developed for DSO regulation, the Network Performance Assessment Model (NPAM), what obstacles there might be and what consequences it might bring when in affect.
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