Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List


PhD_Thesis_Ahmet Cakanel.pdf (3.08 MB)

ETD Abstract Container

Abstract Header

SELF-OPTIMIZATION SYSTEMS DESIGN BASED ON SLIDING MODE CONTROL

Cakanel, Ahmet
http://rave.ohiolink.edu/etdc/view?acc_num=osu1511264100476327

Abstract Details

2017, Doctor of Philosophy, Ohio State University, Electrical and Computer Engineering.
The objective of control systems is to maintain desired output with the best attainable efficiency, in which such performance of many modern technologies is enhanced via minimizing or maximizing some state variables.Optimization problems are occasionally handled under the condition such that extremum value, local plant gain, and required inputs are unknown. Sliding Mode Control (SMC) theory was developed for the plants operate under uncertainty conditions and it exhibits high accuracy, the low sensitivity with respect to parameter variations and disturbances. SMC comply with self-optimization application requires controlling without gradient evaluation or measurement. This is non-conventional control-system problem, cause gradient takes part of the local gain and it can change sign. In the thesis, searching algorithm is designed with monotonously decreasing or increasing function which is tracked by the output of a plant until the extremum point is reached. Along with developed design principle, aforementioned system behavior in the vicinity of extremum is investigated through deeper analyses, cause the local gain of the plant tends to zero and SMC inherently suffers from the presence of high-frequency oscillations so called, chattering. This scope is considered as the theoretical part of the thesis and it is complemented with a comparison of other developed methodologies apply gradient vector evaluation. Generalization of the proposed method is demonstrated for multi-dimensional optimization. Beyond theoretical part, three self-optimization problems are under consideration, which is frequency control of DC/AC inverters implemented on induction motors, output maximization of Underground Coal Gasi cation (UCG) power plants and capability enhancement of a three-dimensional particle tracking a system by integration of an electrically focus-tunable lens. The objective of minimizing the switching-frequency of DC/AC inverters with the desired width of hysteresis results in decreasing heat losses in the power converter. Moreover, decreasing the width of hysteresis loop with remaining the level of admissible frequency will increase the accuracy of inverters. Gasi cation of coal deep below the earth surface, known as the Underground Coal Gasi cation (UCG) process, is very sensitive to flow rate of oxidants. However, the most critical factor is the steam to oxygen ratio in the input flow rate. Sliding modes based static self-optimization is applied to the UCG process which takes into consideration the inlet pressure of the UCG reactor adjusts the steam to oxygen a ratio such that the reactor output, which is the calori c value of the product gases is maximized. The simulation results are presented for the validated UCG model to emphasize the effectiveness of the algorithm. SMC self-optimization model is used for tracking an axillary moving microscopic particle of electrically focus tunable lens. Using lenses mounted on mechanical actuators are not ecient against limited movement range, slower response times and vibrations in the system. These drawbacks are often handled by using mathematical models to estimate the state feedbacks before designing the control system. However, the SM the self-optimizing design does not require state feedback information and works by optimizing an output function of the system. The control system is then successfully simulated.
VADIM I. UTKIN (Advisor)
125 p.
Electrical Engineering; Engineering
Sliding Mode Control, Self-Optimization, Extremum Seeking

Recommended Citations

Citations

  • Cakanel, A. (2017). SELF-OPTIMIZATION SYSTEMS DESIGN BASED ON SLIDING MODE CONTROL [Doctoral dissertation, Ohio State University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=osu1511264100476327

    APA Style (7th edition)

  • Cakanel, Ahmet. SELF-OPTIMIZATION SYSTEMS DESIGN BASED ON SLIDING MODE CONTROL. 2017. Ohio State University, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=osu1511264100476327.

    MLA Style (8th edition)

  • Cakanel, Ahmet. "SELF-OPTIMIZATION SYSTEMS DESIGN BASED ON SLIDING MODE CONTROL." Doctoral dissertation, Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1511264100476327

    Chicago Manual of Style (17th edition)

osu1511264100476327
754
© 2017, all rights reserved.
This open access ETD is published by The Ohio State University and OhioLINK.