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Your search keyword '"Estimation theory"' showing total 7 results
Start Over Descriptor "Estimation theory" Topic electric power Topic least squares
7 results on '"Estimation theory"'

1. State Estimation of the Power System Using Robust Estimator.

Author

Khan, Zahid, Razali, Radzuan B., Daud, Hanita, Nor, Nursyarizal Mohd, and Firuzabad, Mahmud Fotuhi

Subjects
*ELECTRIC power, *ESTIMATION theory, *LEAST squares, *ROBUST control
Abstract

The presence of gross errors in the process data for the power system state estimation (PSSE) algorithm is very crucial as they may severely degrade its results. The conventionally used state estimator is based on the method of the weighted least squares (WLS) which is not robust against the bad measurements that results in larger deviation in output estimates. In this study, a new robust algorithm based on the quasi weighted least squares (QWLS) estimator is presented. The robustness of the QWLS approach is achieved by reducing the impact of bad measurements on the objective function. In the existence of gross errors, the proposed algorithm provides estimates as good as those that are achieved by the conventional method of the WLS when no gross error exists in the process data. The implementation of the proposed algorithm has been illustrated for the case studies on the 6-bus and IEEE 14-bus power networks. The numerical results validate the performance of the proposed estimator in the PSSE algorithm. [ABSTRACT FROM AUTHOR]

Published
2016
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2. Identifying a simplified model for heavy duty gas turbine.

Author

Bahrami, Saeed, Ghaffari, Ali, Hossein Sadati, S., and Thern, Marcus

Subjects
*ELECTRIC power, *ELECTRIC generators, *GENETIC algorithms, *MATHEMATICAL statistics, *ESTIMATION theory
Abstract

A dynamic model was developed for long-term simulation of a heavy duty gas turbine. The model includes the essential control algorithm of the gas turbine as well as the most common outputs and other important intermediate variables. Control algorithm details, such as wind up protection and load limiter algorithm which have large effect on gas turbine transient behavior, are included. The model parameters are identified by applying genetic algorithm and least squares algorithm on regular operational data from a real plant to better match the model response to the real plant. The simulation results have been validated with real plant data and shown to have valid accuracy for many engineering applications. [ABSTRACT FROM AUTHOR]

Published
2014
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3. Robust WLS estimator using reweighting techniques for electric energy systems.

Author

Caro, Eduardo, Mínguez, Roberto, and Conejo, Antonio J.

Subjects
*ELECTRIC power, *ESTIMATION theory, *ROBUST control, *LEAST squares, *ANALYSIS of variance, *EXPERIMENTAL design
Abstract

Highlights: [•] A state estimator based on a weighted least squares model is proposed which is robust against outliers. [•] The RWLS method considers measurement dependencies and its weights are automatically readjusted. [•] Two realistic systems are studied and the results are analyzed using Design of Experiments and ANOVA techniques. [ABSTRACT FROM AUTHOR]

Published
2013
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4. HARMONİK VE SIÇRAMA İÇEREN ELEKTRİK GÜÇ ŞEBEKESİ GERİLİM İŞARETİNE KİLİTLENMENİN YİNELENEN EN KÜÇÜK KARELER METODUYLA İNCELENMESİ

Author

Sayan, H. Hüseyin, Koşalay, İlhan, and Yilmaz, Cemal

Subjects
*ELECTRIC potential, *ELECTRICAL harmonics, *LEAST squares, *ESTIMATION theory, *ELECTRIC power, *SIMULATION methods & models, *INDUSTRIAL efficiency, *MATHEMATICAL statistics, *PHASE shift (Nuclear physics)
Abstract

In this study, recursive least squares method (RLSM) that is one of the adaptable classical methods was used. Firstly forgetting factor was adapted to RLSM. Phase information of voltage signal belonging to an electric power network that contains harmonics and spike was obtained by developed approach. Then responses of the algorithm were investigated for voltage collapse, phase shift and spike. Simulation was implemented by using MATLAB® code. Results of simulation were examined and efficiency of method was presented. [ABSTRACT FROM AUTHOR]

Published
2009

5. STLS Algorithm for Power-Quality Indices Estimation.

Author

Terzija, Vladimir V. and Stanojević, Vladimir

Subjects
*DIGITAL signal processing, *DIGITAL electronics, *ELECTRICAL harmonics, *PARAMETER estimation, *ESTIMATION theory, *LEAST squares, *MATHEMATICAL statistics, *ELECTRIC currents, *ELECTRIC power
Abstract

This paper introduces a new two-stage, self-tuning least-squares digital signal processing algorithm for power-quality (PQ) indices estimation according to the power components and PQ indices definitions given in the IEEE Standard 1459-2000. The algorithm is based on the nonrecursive least error square technique accompanied with an tuning procedure, which generally improves the algorithm properties: the measurement range, the immunity to a random noise, convergence, and accuracy. The presented algorithm models typical signal distortions and it can be used for the real-time PQ indices estimation. In order to estimate signal spectra and fundamental frequency, current and voltage signals are processed in the first algorithm stage, whereas in the second stage, the power components and PQ indices are calculated based on the results obtained from the first stage. To demonstrate the efficiency of the proposed algorithm, the results of computer simulated and laboratory tests are presented. [ABSTRACT FROM AUTHOR]

Published
2008
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6. A state estimation algorithm for identification and measurement of power system harmonics

Author

G. S. Christensen, S. A. Soliman, K. M. El-Naggar, and D. H. Kelly

Subjects
Estimation theory, Dimmer, Energy Engineering and Power Technology, Converters, Least squares, Transmission (telecommunications), Control theory, Harmonics, Harmonic, Electronic engineering, Electric power, Electrical and Electronic Engineering, Algorithm, Mathematics
Abstract

Electrical power networks may be subject to harmonic injection due to the presence of non-linear loads or sources such as converters of all kinds, including HVDC transmission and solid state switching for static VAR systems, and also due to increased use of variable speed motors, dimmer switches, microwave ovens, battery chargers, etc. This paper presents a new application of the least squares parameter estimation error algorithm for the measurement and identification of power system harmonics. The proposed technique uses the digitized bus voltage and current to identify the source, order and amplitude of the harmonic signals. The mathematical model for the algorithm is presented; the effects of data window size, sampling frequency and time reference are also examined.

Published
1990

7. State estimation in power engineering using the Huber robust regression technique

Author

Kyriakides, Elias, Suryanarayanan, S., Heydt, Gerald T., and Kyriakides, Elias [0000-0001-7282-9836]

Subjects
Engineering, Mathematical optimization, Estimation theory, business.industry, Energy Engineering and Power Technology, Least squares, Robust regression, Robustness (computer science), Multicollinearity, Electric power, Power engineering, Electrical and Electronic Engineering, business, Algorithm, Statistical hypothesis testing
Abstract

The least-squares method has been used extensively for state estimation in electric power engineering. However, this method is not always suitable when the process matrix is characterized by structural defects. This letter demonstrates the Huber function technique in a power engineering application. This technique is a slight departure from the least-squares method and downweighs large residuals. A statistical test to identify possible structural imperfections in the model is introduced.

Published
2005

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