Modeling and Stability Analysis of Closed Loop Current-Mode Controlled Ćuk Converter using Takagi-Sugeno Fuzzy Approach

An extensive small-signal analysis of a single-loop current-mode control strategy for a pulse-width-modulated (PWM) boost DC-to-DC power converter operating in continuous conduction mode (CCM) is proposed using a new non-symmetric phase controller. To model the boost power stage, a linear circuit model is used which includes all parasitic components such as the equivalent series resistance (ESR) of the filter capacitor, the ESR of the inductor, the transistor ON-resistance, and the diode forward resistance and offset voltage. A boost power stage design example gives component design equations and will serve to illustrate the closed-loop converter design. A design procedure for the new non-symmetric phase controller is presented. Open-loop and closed-loop circuit models and transfer functions are derived for the boost PWM converter and illustrated by Bode plots. An approach is presented for simplifying closed-loop transfer functions, using Euler's identity, into a format which is conducive to modeling in any high level programming language on a personal computer. Bode plots are obtained using a data analysis software package Axum 3.0 which combines a programming language, spread-sheet, and publication quality technical graphics. The proposed control scheme directly controls the inductor current and indirectly controls the load current and output voltage. The closed-loop transfer functions of the proposed control scheme do not contain a righthalf plane (RHP) zero, in contrast to the closed-loop transfer functions of a single-loop voltage-mode control scheme. The absence of the RHP zero provides better stability by making it easier to obtain large or specified gain and phase margins.

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Stability Analysis and Control of Nonlinear Phenomena in Boost Converters Using Model-Based Takagi–Sugeno Fuzzy Approach

IEEE Transactions on Circuits and Systems I Regular Papers ◽

10.1109/tcsi.2009.2019389 ◽

2010 ◽

Vol 57 (1) ◽

pp. 200-212 ◽

Cited By ~ 39

Author(s):

K. Mehran ◽

D. Giaouris ◽

B. Zahawi

Keyword(s):

Stability Analysis ◽

Nonlinear Phenomena ◽

Fuzzy Approach ◽

Boost Converters ◽

Model Based ◽

Takagi Sugeno ◽

And Control

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Design and Stability Analysis of a QFT Pressure Controller of a Hydraulic Actuator Using Takagi-Sugeno Fuzzy Model

ASME/BATH 2015 Symposium on Fluid Power and Motion Control ◽

10.1115/fpmc2015-9636 ◽

2015 ◽

Author(s):

Masoumeh Esfandiari ◽

Nariman Sepehri

Keyword(s):

Stability Analysis ◽

Closed Loop ◽

Nonlinear Function ◽

Loop System ◽

Performance Criteria ◽

Parametric Uncertainties ◽

Hydraulic Actuator ◽

Closed Loop System ◽

Takagi Sugeno ◽

Operating Points

In this paper, a robust, fixed-gain, and linear controller is designed for the output pressure of an electro-hydraulic actuator with parametric uncertainties. Quantitative feedback theory (QFT) is selected as the design technique. The objective is to satisfy specified performance criteria in terms of tracking, stability, and disturbance rejection. To design the QFT controller, the required family of frequency responses is obtained by linearizing the hydraulic nonlinear function around operating points of interest, and constructing an equivalent linear plant set. As a result, the stability of the closed-loop system is guaranteed only around the limited number of operating points, and specified values for system parameters. To overcome this limitation, Takagi-Sugeno (T-S) fuzzy modeling is employed. This way the nonlinear stability of the closed-loop system is investigated and ensured for a continuous range of parametric uncertainties and region of operating points. Having successful results from stability analysis, the QFT controller is applied on the experimental set-up. The experimental results are in accordance with the specified criteria.

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