Robust local parameter estimator based on least absolute value estimator

2017-01-01
ÖZDEMİR, VOLKAN
Göl, Murat
Changes in weather conditions such as temperature and humidity, miscommunication between the control center and circuit breaker transducers and tap changers, and inaccurate manufacturing data may cause parameter errors. Because of incorrect parameters, the state estimator may provide biased state estimates, which may lead to many serious economic and operational results. In order to prevent that, one must identify and correct those parameter errors. This work proposes a local parameter estimator based on the least absolute value (LAV) estimator, which is known to be robust against bad measurements, i.e. measurements with gross error. Considering the increasing number of phasor measurement units (PMUs), as well as their fast refresh rate and high accuracy, the proposed method will employ PMU measurements in local parameter estimation. In general, a PMU measures the current phasor flowing through a branch and the voltage phasor of the sending bus of that branch. However, those two measurements are not sufficient to estimate the parameters of the considered branch. Therefore, multiple measurements taken at different time instants will be used in the parameter estimation process for measurement redundancy, assuming that the line parameters and transformer taps are constant. The proposed method also assumes that the state estimates are available. The LAV estimator is computationally expensive, but it provides unbiased state estimates even in the presence of bad data, provided that enough measurement redundancy is available. This deficiency will be eliminated by performing local parameter estimation.
Turkish Journal Of Electrical Engineering And Computer Sciences

Suggestions

A Robust Parameter Estimation Method Based on LAV Estimator
Özdemir, Volkan; Göl, Murat (2015-07-09)
In a power system, it is known that parameters may carry small errors due to the weather conditions, such as temperature and humidity changes, as well as gross errors due to the miscommunication between the control center and circuit breakers and tap changers. Those incorrect parameters may cause biased state estimates, which may have serious results. Therefore, those parameter errors should be identified and corrected. Considering the increasing number of Phasor Measurement Units (PMUs), in this paper it i...
A Local parameter estimator based on robust LAV estimation
Özdemir, Volkan; Göl, Murat; Department of Electrical and Electronics Engineering (2015)
There are parameter errors in power system models due to the change of weather conditions, such as temperature and humidity changes, miscommunication between the control center and the transducers of circuit breakers and tap changers, etc. Because of the incorrect parameters, the state estimator may provide biased state estimates which may lead to many serious economic and operational results. In order to prevent that, one must identify and correct those parameter errors. This work proposes a local paramete...
Critical behaviour of the dielectric constant for the smectic AC* transition under the electric field in ferroelectric liquid crystals
Yurtseven, Hasan Hamit (2012-01-01)
The temperature dependencies of the dielectric constant and the tilt angle (order parameter) are calculated under the electric field for the smectic A-smectic C* (AC*) transition in 4-(3-methyl-2-chlorobutanoyloxy)-4'-heptyloxybiphenyl (A7). The dielectric constant is fitted to the experimental data by using our mean field model with the biquadratic coupling between the spontaneous polarisation P and the tilt angle theta. Our results show that the mean field model with the P-2 theta(2) coupling describes sa...
Adaptive fuzzy hysteresis band current control for reducing switching losses of hybrid active power filter
Durna, Emre (2018-05-01)
Although hysteresis band current control is an easy to implement and robust control method for industrial power electronics converters, it has also some disadvantages like variable and high switching frequency causing high switching losses. In this study, a novel adaptive fuzzy hysteresis band current control system is proposed by making use of fuzzy expressions of both hybrid active power filter (HAPF) current and integral of its harmonic components to reduce the switching losses of three-phase three-wire ...
Detection of some parameters of induction motors a proposal and its verification
Özlü Ertan, Hatice Gülçin; Colak, Baris (2007-11-30)
This paper describes a novel approach for offline stator leakage inductance estimation method that can be used for self-tuning of induction motor drives. The paper briefly describes the theory behind the approach. The proposed method is based on applying a DC voltage to the motor windings and measuring the DC current that flows in the circuit over a short interval of time. The measured variables are DC quantities and relatively noise free as compared to some other available methods. The proposed approach is...
Citation Formats
V. ÖZDEMİR and M. Göl, “Robust local parameter estimator based on least absolute value estimator,” Turkish Journal Of Electrical Engineering And Computer Sciences, pp. 3143–3151, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41229.