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Summary form only given: This paper presents a computer model for the probabilistic representation of wind farms generation for reliability studies, which can provide an annual estimation of energy production and calculate several performance indices. The model combines the stochastic characteristics of wind speed with the operational information of the turbines, such as the failure and repair rates,...
Summary form only given. Harmonic resonance is closely related to the singularity of a network admittance matrix. The smallest eigenvalue of the matrix defines the mode of harmonic resonance. This paper applies this eigenvalue theory and proposes a method to determine which network components have significant contributions to a harmonic resonance phenomenon. The basic idea is to calculate the sensitivities...
Summary form only given. This paper presents a novel nonlinear optimal controller for a static compensator (STATCOM) connected to a power system, using artificial neural networks and fuzzy logic. The action dependent heuristic dynamic programming (ADHDP), a member of the adaptive critic designs (ACD) family, is used for the design of the STATCOM neuro-fuzzy controller. This neuro-fuzzy controller...
Summary form only given. The split-winding arrangement requires special short circuit design considerations. During short circuit conditions, there is a considerable distortion of the leakage field, which in turn produces high axial short circuit forces. This paper deals with the computation and analysis of electromagnetic forces in windings of split-winding transformers. A nonlinear-transient field-circuit...
The presentation will describe new trends in open source software components with special emphasis on its impact on the next generation of energy systems.
After liberalisation of the electricity market in 1998, Germany relied on negotiated third party access to the electricity networks, basically meaning no regulation of network charges. As expected, this was not effective. In June 2005, the German government installed both a regulator (Bundesnetzagentur, BNetzA) and authorised regulation of electricity network charges. The Energy Act provided for cost...
Summary form only given. A probabilistic method for a pool based combined energy and reserve market, that considers both generators and interruptible loads (ILs), is proposed in this paper. We minimize generation production cost together with the cost associated with expected energy not supplied (EENS) due to outages of generating units and failures of ILs to supply the reserve when required. The...
Summary form only given. This paper presents an analysis of transmission line modeling when the soil conductivity and permittivity are treated as frequency dependent. It also presents a methodology to include this particular behavior on frequency dependence realization of transmission lines and cables. The frequency dependent soil parameters can be synthesized with a simple first order model. It demands...
Summary form only given. This paper presents closed-form steady-state, fundamental-frequency models of power electronic converter systems for coupling distributed resource (DR) units to the utility power grid. Based on the developed models, the paper introduces a two-step power flow analysis approach that accurately and efficiently represents electronically-coupled DR units. A feature of the proposed...
Summary form only given. This paper presents the application of a space vector modulation (SVM) strategy for a ulti-module HVDC converter system that (i) enables low switching frequency, (ii) eliminates/minimizes AC-side voltage harmonics, particularly low-order harmonics, and (iii) provides maximum AC-side fundamental voltage component. The SVM strategy is based on a sequential sampling technique...
Summary form only given. This paper presents a digital hardware realization of a real-time simulator for a complete induction machine drive using a field programmable gate array (FPGA) as the computational engine. The simulator was developed using very high speed integrated circuit hardware description language (VHDL), making it flexible and portable. A novel device-characteristic based model suitable...
Summary form only given. In non-sinusoidal situations, power components definitions contained in the IEEE Standard 1459-2000 are based on a frequency-domain approach using Fourier transform (FT). The frequency-domain approach can provide amplitude-frequency spectrum while loosing time-related information. Moreover, the FT carries a heavier computational burden. To overcome these limitations, definitions...
Summary form only given. Power components definitions contained in the IEEE Standard 1459-2000 for unbalanced three-phase systems with non-sinusoidal situations are represented in the frequency domain based on Fourier Transform (FT). However, FT suffers from the high computational effort especially when the number of phases increases and it is unable to provide information concerning time content...
Wind driven induction generators are popular due to their robust construction and performance. Typically, they are connected to a distribution system through a feeder and may cater to a local load of comparable size. Wind characteristics are unpredictable, sometimes causing large bursts of power flow. During such bursts, the feeder voltage regulation is problematic, possibly leading to a collapse...
The Government of the Republic of Ireland and the relevant Northern Ireland Civil service department are engaged in an Al-Island renewable grid study. This paper will report on the results of that study.
Since 1998, the CAISO has procured ancillary services in the day-ahead and hour-ahead market in a sequential manner after the congestion management is completed. As the CAISO is implementing its market redesign technology upgrade (MRTU), the CAISO will be co-optimizing the procurement of ancillary services and energy.
Summary form only given. A new topologically-correct hybrid transformer model is developed for low- and mid-frequency transient simulations. Power transformers have a conceptually simple design, but behaviors can be very complex. Selection of the most suitable representation for a given behavior depends on the type of transformer to be simulated, the frequency range, and other factors such as the...
Summary form only given. The topological structure and basic approaches for parameter estimation for a new hybrid transformer model are presented in Part I of this two-paper set. Part II deals with the model benchmarking and also discusses additional methods for parameter estimation based on laboratory measurements. The simulation results confirm the validity of the model for the low- and medium-frequency...
In the paper a new improved recursive Newton type algorithm (IRNTA) suitable for various measurement applications in the electric power systems is presented. Here it is applied for power quality indices estimation according to the IEEE Standard 1459-2000. Basically the algorithm is a recursive nonlinear estimator, improved with a strategy of sequentially tuning of the forgetting factor. This approach...
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