Development of fast and robust spectral decomposition method for nonlinear industrial loads with current frequency spectrum rich in harmonic and interharmonic content

Download
2016
Uz-Loğoğlu, Eda
Nonlinear industrial loads such as AC arc furnaces and induction melting furnaces with resonant converters exhibit highly distorted currents rich in harmonic and interharmonic frequency components. Detection of these harmonics and interharmonics is crucial for applying countermeasures to achieve power quality requirements defined by the regulations of the power system operator. Fast and accurate harmonic and interharmonic detection in a power system experiences some difficulties due to the fact that power system frequency varies in time while the harmonic and interharmonic content is also time-varying. Hence Fourier Analysis based methods are slow and inaccurate to be used with compensation systems such as active filters. The aim of this thesis is to develop methods both fast and robust under time-varying fundamental frequency and spectrum conditions as well as in cases of unbalanced currents drawn by nonlinear industrial loads. Therefore, in this thesis, a novel method which combines the multiple synchronous reference frame (MSRF) analysis with the Kalman filter is proposed in order to take the advantage of the prediction capability of the Kalman filter and the accurate performance of the MSRF analysis. This algorithm, which provides the positive- and negative-sequences of all harmonic and interharmonic components under consideration, is implemented on the NVIDIA Jetson TX1 graphics processing unit (GPU). Results proves that the decomposition of the harmonic and the interharmonic components is achieved accurately with a microsecond latency that allows the proposed algorithm to be used in a real-time operation.

Suggestions

Investigation of subsynchronous resonance risk in the 380 kv Turkish electric network
Ozay, N.; Güven, Ali Nezih (null; 1988-12-01)
Subsynchronous resonance (SSR) occurs when a resonant frequency of a series compensated transmission system interacts with a natural frequency of the turbine prime mover. This form of SSR is referred to as torsional interaction which, under certain conditions, may become self-excited and cause serious damage to electrical equipment and turbine shafts. The presence of a thermal power plant (Kangal) in the close vicinity of a group of series capacitors in Eastern Turkey necessitated a careful investigation of...
Design and implementation of a voltage source converter based statcom for reactive power compensation and harmonic filtering
Çetin, Alper; Ermiş, Muammer; Department of Electrical and Electronics Engineering (2007)
In this thesis, design and implementation of a distribution-type, voltage source converter (VSC) based static synchronous compensator (D-STATCOM) having the simplest converter and coupling transformer topologies have been carried out. The VSC STATCOM is composed of a +/- 750 kVAr full-bridge VSC employing selective harmonic elimination technique, a low-pass input filter, and a /Y connected coupling transformer for connection to medium voltage bus. The power stage of VSC based STATCOM is composed of water-co...
Online Characterization of Interharmonics and Harmonics of AC Electric Arc Furnaces by Multiple Synchronous Reference Frame Analysis
Uz-Logoglu, Eda; Salor, Ozgul; Ermiş, Muammer (2016-05-01)
In this paper, a multiple synchronous reference frame (MSRF) analysis framework is developed to determine the positive-and negative-sequence components of all interharmonic and harmonic currents produced by alternating current electric arc furnace (AC EAF) installations, which can be considered as balanced but asymmetrical three-phase, three-wire loads on the power system. The aim of developing the MSRF analysis framework is twofold; deep understanding of the EAF characteristics, and fast and accurate gener...
Online characterization of interharmonics and harmonics of AC electric arc furnaces by multiple synchronous reference frame analysis
Uz Loğoğlu, Eda; Salor, Özgül; Ermiş, Muammer (2015-10-18)
In this paper, a multiple synchronous reference frame (MSRF) analysis framework is developed to determine the positive- and negative -sequence components of all interharmonic and harmonic currents produced by alternating current electric arc furnace (AC EAF) installations, which can be considered as balanced but asymmetrical three-phase, three -wire loads on the power system. The aim of developing the MSRF analysis framework is two -fold; deep understanding of the EAF characteristics, and fast and accurate ...
Design, Implementation, and Operation of a New C-Type 2nd Harmonic Filter for Electric Arc and Ladle Furnaces
Gercek, Cem Ozgur; Ermiş, Muammer; Ertas, Arif; Kose, Kemal Nadir; Unsar, Ozgur (2011-07-01)
In this paper, the transient overvoltage suppression capability and harmonic filtering performance of C-type 2nd harmonic filters (HFs) are optimized by using two-stage damping resistors; one is permanently connected to the filter circuit, while the other one is switched on by back-to-back connected thyristors during furnace transformer and HF energization periods. However, in conventional C-type 2nd HFs, there is only one damping resistor, which is permanently connected to the filter circuit. In convention...
Citation Formats
E. Uz-Loğoğlu, “Development of fast and robust spectral decomposition method for nonlinear industrial loads with current frequency spectrum rich in harmonic and interharmonic content,” Ph.D. - Doctoral Program, Middle East Technical University, 2016.