Study on the Underground Thermal Environment around Wells for a Design Method of Open-Loop Geothermal System

In this paper, a new design method with performance improvements of multiloop controllers for multivariable systems is proposed. Precise expression is developed to show the relationship between the dynamic- and steady-state characteristics of the multiloop control system and its parameters. First, an equivalent transfer function (ETF) is introduced to decompose the multivariable system, based on which the multiloop controller parameters are calculated. According to the ETF matrix property, an analytical expression for the PI controller for multivariable systems is derived in terms of substituting the ETF matrix for the inverse open-loop transfer function. In the proposed controller design method, no approximation of the inverse of the process model is needed, implying that this method can be applied to some multivariable systems with high dimensions. The simulation results obtained from several examples demonstrate the effectiveness of the proposed method.

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Back Stepping Control of the Magnetic Suspension System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.189.364 ◽

2012 ◽

Vol 189 ◽

pp. 364-368

Author(s):

Zhao Yuan Wang ◽

Guo Qing Wu

Keyword(s):

Controller Design ◽

Design Method ◽

Open Loop ◽

Suspension System ◽

Magnetic Suspension ◽

Control Performance ◽

State Variables ◽

Simulink Simulation ◽

Magnetic Suspension System ◽

Back Stepping Control

The magnetic suspension system is a strong nonlinear, uncertain and open-loop unstable system. All of these factors have increased the difficulty of maglev controller design. Considering the single freedom maglev system as the research object in this paper, structure analysis and modeling design are conducted for the system. By choosing new state variables, the system model is transformed. On the basis of that, we use back stepping design method to design the nonlinear suspension controller. Control performance of the controller can be observed by the Matlab/Simulink simulation.

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Performance Analysis for Open-loop Geothermal System with Spill-way technology by Real-scale Experiment

Korean Journal of Air-Conditioning and Refrigeration Engineering ◽

10.6110/kjacr.2018.30.4.186 ◽

2018 ◽

Vol 30 (4) ◽

pp. 186-194

Author(s):

Hong kyo Kim ◽

Sangmu Bae ◽

Yujin Nam ◽

Oun Jeoun ◽

Jong Hyun Oh ◽

...

Keyword(s):

Performance Analysis ◽

Open Loop ◽

Geothermal System ◽

Scale Experiment ◽

Real Scale

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New Microstrip Diplexer for Recent Wireless Applications

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i3.4.16754 ◽

2018 ◽

Vol 7 (3.4) ◽

pp. 96 ◽

Cited By ~ 1

Author(s):

Yaqeen S. Mezaal ◽

Seham A. Hashim ◽

Aqeel H.Al-fatlawi ◽

Hussein A. Hussein

Keyword(s):

Insertion Loss ◽

Return Loss ◽

Design Method ◽

Open Loop ◽

Coupled Resonators ◽

Wireless Applications ◽

Frequency Responses ◽

Operating Band ◽

Dual Channel ◽

Better Than

In this study, dual-channel diplexer using microstrip open loop coupled resonators has been designed and simulated; each channel has two operating band frequencies. This microstrip diplexer is designed for (1.424/1.732GHz) for first channel and (2.014/2.318GHz) for second channel. The simulated results for this device have insertion loss (1.8 and 1 dB) at load 1, and (1.5 and 3 dB) at load 2. Additionally, it has reasonable return loss magnitudes better than 10 dB and effective isolation between channels of35 dB. The proposed design has shown an uncomplicated topology, an effectual design method, small circuit size and narrowband frequency responses that are fitting for multi service wireless schemes.

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On-Line Identification of Open-Loop Frequency Response and Two-Degree-of-Freedom Design Method of PID Control Systems

Transactions of the Institute of Systems Control and Information Engineers ◽

10.5687/iscie.11.41 ◽

1998 ◽

Vol 11 (1) ◽

pp. 41-49 ◽

Cited By ~ 1

Author(s):

Eiko FURUTANI ◽

Mituhiko ARAKI

Keyword(s):

Frequency Response ◽

Control Systems ◽

Pid Control ◽

Design Method ◽

Open Loop ◽

Degree Of Freedom ◽

Line Identification ◽

On Line ◽

Two Degree Of Freedom

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Simulation analysis of a single well geothermal system with open-loop structure

Geothermics ◽

10.1016/j.geothermics.2021.102338 ◽

2022 ◽

Vol 100 ◽

pp. 102338

Author(s):

Kunqing Jiang ◽

Xianbiao Bu

Keyword(s):

Simulation Analysis ◽

Open Loop ◽

Geothermal System ◽

Loop Structure ◽

Single Well

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Robust Control Design of a Single Degree-of-Freedom Magnetic Levitation System by Quantitative Feedback Theory

ASME/ISCIE 2012 International Symposium on Flexible Automation ◽

10.1115/isfa2012-7181 ◽

2012 ◽

Cited By ~ 1

Author(s):

Feng Tian ◽

Mark Nagurka

Keyword(s):

Robust Control ◽

Magnetic Levitation ◽

Design Method ◽

Control Design ◽

Open Loop ◽

Quantitative Feedback Theory ◽

Single Degree Of Freedom ◽

Single Degree ◽

Maglev System ◽

Robust Control Design

A magnetic levitation (maglev) system is inherently nonlinear and open-loop unstable because of the nature of magnetic force. Most controllers for maglev systems are designed based on a nominal linearized model. System variations and uncertainties are not accommodated. The controllers are generally designed to satisfy gain and phase margin specifications, which may not guarantee a bound on the sensitivity. To address these issues, this paper proposes a robust control design method based on Quantitative Feedback Theory (QFT) applied to a single degree-of-freedom (DOF) maglev system. The controller is designed to successfully meet the stability requirement, robustness specifications, and bounds on the sensitivity. Experiments verify that the controller maintains stable levitation even with 100% load variation. Experiments prove that it guarantees the transient response design requirements even with 100% load change and 39% model uncertainties. The QFT control design method discussed in this paper can be applied to other open-loop unstable systems as well as systems with large uncertainties and variations to improve system robustness.

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