dc.contributor.advisor |
Kükrer, Osman |
|
dc.contributor.author |
Makhamreh, Hamza Ahmed M. |
|
dc.date.accessioned |
2023-09-25T12:05:41Z |
|
dc.date.available |
2023-09-25T12:05:41Z |
|
dc.date.issued |
2019-01 |
|
dc.date.submitted |
2019 |
|
dc.identifier.citation |
Makhamreh, Hamza Ahmed M. (2019). Control Methods for Multilevel Converters. Thesis (Ph.D.), Eastern Mediterranean University, Institute of Graduate Studies and Research, Dept. of Electrical and Electronic Engineering, Famagusta: North Cyprus. |
en_US |
dc.identifier.uri |
http://hdl.handle.net/11129/5752 |
|
dc.description |
Doctor of Philosophy in Electrical and Electronic Engineering. Institute of Graduate Studies and Research. Thesis (Ph.D.) - Eastern Mediterranean University, Faculty of Engineering, Dept. of Electrical and Electronic Engineering, 2019. Supervisor: Prof. Dr. Osman Kükrer. |
en_US |
dc.description.abstract |
This thesis aims to develop new control methodologies for the Packed U-Cell (PUC)
converter. The main problem lies in the structure of the PUC converter, where it is a
hybrid type of multilevel converter (MLC) similar to cascaded H-bridge converters.
From the control prospective, the topology has discrete digital control inputs, thus
conventional modulation techniques cannot be directly applied to the converter.
Proper control methods have to be introduced in order to make use of the great
advantages of the PUC converter. These control methods have to be simple in
implementation for industrial environment with low switching frequency.
Additionally, the newly proposed control methods should have advantages over the
existing ones.
In the first attempt of this thesis, a modified version of model predictive control
(MPC) has been integrated to control grid connected PUC inverters. Mainly, the cost
function is formulated to guarantee the stability of the controlled system. Then, the
gains associated with the controlled variables are eliminated in order to simplify the
control. The proposed controller has shown great features in terms of stability and
low average switching frequency.
In the second attempt of this thesis, the interesting features of sliding mode theory are
utilized to serve the control problem in a better way. The proposed controller is very
simple to implement with low computation time, which reduces the computational
burden on the controller. The controller aims to allocate the control input which
stabilizes both the grid current and the auxiliary capacitor voltage in the grid
connected PUC inverter.
Lastly, the control problem of the PUC rectifier with a dual output is targeted using
Lyapunov-based MPC. This attempt is done in order to prove the workability of the
controller for three control variables. In this method Lyapunov-based MPC doesn’t
require gain tuning as in the PUC inverter problem. Load current measurements are
eliminated by making use of the mathematical model of the PUC converter. This
significantly reduces the cost and simplifies the control algorithm, where no current
sensors are used for the load measurements.
For all proposed methods, simulations and experimental tests were done in order to
justify the correctness of the proposed methods. Dynamic tests and parameter
mismatch tests are carried out to measure the controller response and to show the
robustness feature of the proposed controllers.
Keywords: Finite control set, Lyapunov control, model predictive control, multilevel
converter, packed U-Cell converter, sliding mode control. |
en_US |
dc.description.abstract |
OZ¨:
Bu tezin amacı PUC c¸evirgec¸ler ic¸in yeni denetleme yontemleri gelis¸tirmektir. Bu ¨
c¸evirgec¸lerde esas sorun, ardarda baglanmıs¸ H-k ˘ opr ¨ uye benzer c¸oklu-seviyeli melez ¨
bir sınıf olmalarından kaynaklanan yapılarından dolayıdır. Denetleme ac¸ısından
bakıldıgında, bu c¸evirgec¸lerin topolojisinde ayrık ve sayısal denetleme giris¸leri vardır. ˘
Dolayısıyla, geleneksel kipleme yontemleri bu c¸evirgec¸lere do ¨ grudan uygulanamaz. ˘
PUC c¸evirgec¸lerinin avantajlarından faydalanan uygun denetleme yontemlerinin ¨
gelis¸tirilmesi gerekir. Bu yontemlerin, end ¨ ustriyel ortamlara uygun ve d ¨ us¸¨ uk¨
anahtarlama sıklıklarına sahip basit bir s¸ekilde gerc¸ekles¸tirilebilmeleri gerekir. Buna
ek olarak, onerilen denetleme y ¨ ontemlerinin var olanlara g ¨ ore avantajlarının olması ¨
gerekir. Model ong ¨ or¨ uc¨ u denetlemenin (M ¨ OD) c¸oklu-seviyeli c¸evirgec¸ler gibi ¨
endustriyel uygulamalarda kullanılması da dikkate alınarak, bu y ¨ ontemin ¨
farklılas¸tırılmıs¸ bir tur¨ u s¸ebekeye ba ¨ glı PUC evirgec¸lerinin denetlenmesi ic¸in ˘
gelis¸tirilmis¸tir. Esas olarak eder is¸levi, denetlenen sistemin kararlılıgını garanti ˘
edecek s¸ekilde duzenlenmis¸tir. Denetlenen de ¨ gis¸kenlere ait kazanc¸lar, bazı ˘
varsayımlar kullanılarak ve denetlemeyi basitles¸tirmek amacı ile elenmis¸tir. Onerilen ¨
denetleyicinin, kararlılık ve dus¸¨ uk ortalama anahtarlama sıklı ¨ gı gibi ˘ onemli ¨
ozelliklere sahip oldu ¨ gu g ˘ ozlenmis¸tir. ¨
Bu tezdeki ikinci giris¸imde, denetleme sorununa daha iyi c¸oz¨ umler getirmek ic¸in, ¨
kayan kiplemeli denetleme kuramının onemli ¨ ozelliklerinden yararlanılmıs¸tır. ¨
Onerilen denetleyici, denetleyicinin ¨ uzerindeki hesaplama y ¨ uk¨ un¨ u azaltan, oldukc¸a ¨
basit bir tarzda gerc¸ekles¸tirilebilmektedir. Denetleyicinin amacı denetleme giris¸lerini,
s¸ebekeye baglı PUC evirgec¸inin s¸ebekeye verdi ˘ gi akımı ve sı ˘ gac¸ gerilimini kararlı ˘
duruma getirecek s¸ekilde belirlemektir.
Son olarak, c¸ift c¸ıkıs¸lı PUC dogrultucuların denetleme sorununu Lyapunov tabanlı ˘
MOD kullanarak c¸ ¨ ozmek hedeflendi. Bu giris¸im, ¨ uc¸ de ¨ gis¸kenli denetleme durumunda ˘
denetleyicinin c¸alıs¸abilir oldugunu g ˘ ostermek ic¸in yapıldı. ¨ Onerilen y ¨ ontemde, PUC ¨
evirgec¸inde oldugu gibi, Lyapunov tabanlı M ˘ OD kazanc¸ ayarına gereksinim ¨
duymamaktadır. PUC c¸evirgec¸inin matematiksel modeli kullanılarak yuk akımı ¨
olc¸ ¨ umleri elenmis¸tir. Bu da, denetleme algoritmasını basitles¸tirmis¸ ve akım ¨
duyac¸larına gereksinimi ortadan kaldırarak ederi onemli ¨ olc¸ ¨ ude azaltmıs¸tır. ¨
Onerilen ve PUC topolojisine uygulanan denetleme y ¨ onteminin bas¸arımını g ¨ ostermek ¨
amacıyla benzetim ve deney sonuc¸ları sunulmus¸tur. Denetleyicinin yanıt hızını
olc¸mek ve sa ¨ glamlık ˘ ozelli ¨ gin g ˘ ostermek amacı ile dinamik ve parametre uyus¸mazlı ¨ gı˘
sınamaları yapılmıs¸tır.
Anahtar Kelimeler: Sınırlı denetim kumesi, model ¨ ong ¨ or¨ ul¨ u denetim, c¸ok katmanlı ¨
c¸evirgec¸, istiflenmis¸ U-hucre c¸evirgec¸, kayan kipli denetim. |
en_US |
dc.language.iso |
eng |
en_US |
dc.publisher |
Eastern Mediterranean University (EMU) - Doğu Akdeniz Üniversitesi (DAÜ) |
en_US |
dc.rights |
info:eu-repo/semantics/openAccess |
en_US |
dc.subject |
Electrical and Electronic Engineering |
en_US |
dc.subject |
Electric power systems--Power converters |
en_US |
dc.subject |
Electric current converters |
en_US |
dc.subject |
Control devices--Electrical engineering |
en_US |
dc.subject |
Voltage-frequency converters |
en_US |
dc.subject |
Finite control set |
en_US |
dc.subject |
Lyapunov control |
en_US |
dc.subject |
model predictive control |
en_US |
dc.subject |
multilevel converter |
en_US |
dc.subject |
packed U-Cell converter |
en_US |
dc.subject |
sliding mode control |
en_US |
dc.title |
Control Methods for Multilevel Converters |
en_US |
dc.type |
doctoralThesis |
en_US |
dc.contributor.department |
Eastern Mediterranean University, Faculty of Engineering, Dept. of Electrical and Electronic Engineering |
en_US |