Grid impedance estimation based adaptive controller design for back-to-back wind turbine power converters for stable operation in distorted and weak grid

Download

index.pdf

Date

2019

Author

Temiz, Hakan

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

60
views

20
downloads

This thesis involves grid impedance estimation based adaptive controller design for back-to-back wind turbine power converters for stable operation in distorted and weak grid. The study focuses on the low frequency harmonic elimination of injected current to the grid under distorted grid conditions and maintaining system stability under wide range of grid impedance values for Voltage Source Inverters (VSIs) connected to the grid via LCL filter. To eliminate 5th and 7th harmonics of the injected current, a current controller with harmonic compensator is developed on the grid side controller. The system stability is evaluated by means of several control methods and ensured by adjusting the parameters of Phase Locked Loop (PLL) based on real-time estimated grid impedance. The control design is analyzed by detailed computer simulations. Obtained results are verified by laboratory experiments with a 300 kW wind turbine system which consists of squirrel cage induction generator, IGBT based back-to-back converter and LCL filter. Different operating conditions are considered to provide a through performance evaluation of the designed system.

Subject Keywords

Wind power., Keywords: Grid-connected inverter, adaptive control, weak grid, distorted grid, PRBS injection

URI

http://etd.lib.metu.edu.tr/upload/12624035/index.pdf
https://hdl.handle.net/11511/44715

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Performance Evaluation and Comparison of Single-Phase and Two-Phase Interleaving Flyback Micro-Inverters for Grid Connected PV Systems Kavurucu, Semih; Hava, Ahmet Masum (2014-06-04) Flyback converter based single-stage, microinverters are attractive solution for interfacing individual PV modules to the grid due to their low cost, high performance, ease of implementation, and galvanic isolation. In such applications, discontinuous conduction mode (DCM) of operation and interleaving techniques bring additional size and performance advantages such as eliminating reverse recovery loss, switching stress, EMI radiation, and improving efficiency. This paper focuses on performance evaluation o...
Performance Evaluation and Selection of PWM Switching and Control Methods for Grid Connected Modular Multilevel Converters Ciftci, Baris; Hava, Ahmet Masum (2015-09-24) This paper focuses on the determination of suitable carrier based pulse width modulation (PWM) switching and control methods for grid connected modular multilevel converters (MMCs). Characterization of various level-shifted and phase-shifted carrier based PWM methods are provided in terms of output voltage waveforms both for N+1 and 2N+1 level output phase voltages. Carrier based PWM method based control approaches are evaluated for MMC. Performances of different control methods are evaluated and compared f...
Design of Grid Connected PWM Converters Considering Topology and PWM Methods for Low-Voltage Renewable Energy Applications Kantar, Emre; Hava, Ahmet Masum (2014-05-21) This paper assesses the feasibility three-phase PWM three-level voltage source converters (VSCs), namely NPC-type VSC (3L-NPC) and T-type VSC (3L-T) as alternatives to standard three-phase PWM two-level VSC (2L-VSC) for low-voltage grid interface applications, The topological performances are compared through a design algorithm regarding varying switching frequency, load condition, modulation index, and converter side inductance under distinct pulse-width modulation methods, Design of the LCL filter is also...
Performance comparison of passive series R and shunt R-C damped LCL filter for grid-connected inverters Temiz, Hakan; Demirok, Erhan; Keysan, Ozan; Turkay, Ali; Cetinkaya, Burak (2019-07-01) LCL filters are widely used in distributed power-generation systems to attenuate high-frequency harmonics caused by pulse-width modulation switching of grid-connected inverters. A resonance occurs due to the series-connected reactive components. In order to damp resonance effects, active and passive damping methods are used. Lower switching frequencies are typically preferred to decrease switching power losses with high-power applications. Thus, control bandwidth of the system is limited and implementation ...
DC Link Capacitor Optimization for Integrated Modular Motor Drives Ugur, Mesut; Keysan, Ozan (2017-06-21) In this paper, selection of optimum DC link capacitor for Integrated Modular Motor Drives (IMMD) is presented. First, a review of IMMD technologies is given and current research and future prospects are studied. Inverter topologies and gate drive techniques are evaluated in terms of DC link performance. The urge for volume reduction in IMMD poses a challenge for the selection of optimum DC link capacitor. DC Link capacitor types are discussed and critical aspects in selecting the DC links capacitor are list...

Citation Formats

H. Temiz, “Grid impedance estimation based adaptive controller design for back-to-back wind turbine power converters for stable operation in distorted and weak grid,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Electrical and Electronics Engineering., Middle East Technical University, 2019.