Robustness and Stability Analysis of a Predictive PI Controller in WirelessHART Network Characterised by Stochastic Delay

As control over wireless network in the industry is receives increasing attention, its application comes with challenges such as stochastic network delay. The PIDs are ill equipped to handle such challenges while the model based controllers are complex. A settlement between the two is the PPI controller. However, there is no certainty on its ability to preserve closed loop stability under such challenges. While classical robustness measures do not require extensive uncertainty modelling, they do not guarantee stability under simultaneous process and network delay variations. On the other hand, the model uncertainty measures tend to be conservative. Thus, this work uses extended complementary sensitivity function method which handles simultaneously those challenges. Simulation results shows that the PPI controller can guarantee stability even under model and delay uncertainties.

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Enhanced performance of PID load frequency controller for power systems

International Journal of Advances in Applied Sciences ◽

10.11591/ijaas.v8.i2.pp117-124 ◽

2019 ◽

Vol 8 (2) ◽

pp. 117

Author(s):

Dola Gobinda Padhan ◽

Suresh Kumar Tummala

Keyword(s):

Power Systems ◽

Closed Loop ◽

Control Structure ◽

Sensitivity Function ◽

Tuning Parameter ◽

Pid Controllers ◽

Small Step ◽

Load Frequency ◽

Simulation Results ◽

Frequency Controller

A novel control structure for designing a PID load frequency controller for power systems is presented. The controller with a single tuning parameter is designed based on a desired closed-loop complementary sensitivity function and Pade approximation. Comparative analysis demonstrates that proposed PID controllers improves the settling time and reduces overshoot effectively against small step load disturbances. Also, the performance and robustness of the controllers have been analyzed and compared. Simulation results show significantly improved performances when compared with recent results.

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Nonlinear Control of Semi-Active MacPherson Suspension System

Volume 6: 1st Biennial International Conference on Dynamics for Design; 14th International Conference on Advanced Vehicle Technologies ◽

10.1115/detc2012-71179 ◽

2012 ◽

Cited By ~ 1

Author(s):

Olugbenga M. Anubi ◽

Carl D. Crane

Keyword(s):

Closed Loop ◽

Control Design ◽

Mr Damper ◽

Suspension System ◽

Time Domain Simulation ◽

Closed Loop System ◽

Output Feedback Controller ◽

Space Frequency ◽

Simulation Results ◽

Active Damper

This paper presents the control design and analysis of a non-linear model of a MacPherson suspension system equipped with a magnetorheological (MR) damper. The model suspension considered incorporates the kinematics of the suspension linkages. An output feedback controller is developed using an ℒ2-gain analysis based on the concept of energy dissipation. The controller is effectively a smooth saturated PID. The performance of the closed-loop system is compared with a purely passive MacPherson suspension system and a semi-active damper, whose damping coefficient is tunned by a Skyhook-Acceleration Driven Damping (SH-ADD) method. Simulation results show that the developed controller outperforms the passive case at both the rattle space, tire hop frequencies and the SH-ADD at tire hop frequency while showing a close performance to the SH-ADD at the rattle space frequency. Time domain simulation results confirmed that the control strategy satisfies the dissipative constraint.

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Application Studies of Immune PI Controller in Double Closed-Loop DC Speed Regulation System

2010 2nd International Workshop on Intelligent Systems and Applications ◽

10.1109/iwisa.2010.5473566 ◽

2010 ◽

Cited By ~ 1

Author(s):

Sue Wang

Keyword(s):

Closed Loop ◽

Pi Controller ◽

Regulation System ◽

Speed Regulation

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Robust Steering and Differential Braking Control for Automated Guidance of Tractor-Semitrailer Combination Vehicles

10.1115/imece2000-2345 ◽

2000 ◽

Author(s):

Jeng-Yu Wang ◽

Masayoshi Tomizuka

Keyword(s):

Rear Axle ◽

Closed Loop ◽

Transient Responses ◽

Model Uncertainties ◽

Yaw Stability ◽

Angular Velocities ◽

Simulation Results ◽

Braking Control ◽

Line Pressure ◽

Lateral Error

Abstract In this paper, a robust linear steering and differential braking controller is designed for the automated guidance of tractor-semitrailer combination vehicles using the H∞ loop-shaping methodology. Only the articulation angle, the lateral errors at the front and rear axle of the tractor, and the angular velocities of the rear wheels of the trailer or the brake line pressure signals, are assumed to be available for the synthesis of control inputs. The controller is designed to ensure the robustness to model uncertainties due to variations in vehicle longitudinal speed, road adhesion coefficient and trailer cargo load. Closed-loop simulation results show the robustness of the proposed controller and the resulting smaller lateral error at the trailer end when compared to the controller using the steering input only. More damped transient responses of articulation angle when using the steering and braking control also improve the yaw stability of the trailer.

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SET STABILIZATION OF A MODIFIED CHUA'S CIRCUIT

International Journal of Bifurcation and Chaos ◽

10.1142/s0218127405012181 ◽

2005 ◽

Vol 15 (02) ◽

pp. 567-604 ◽

Cited By ~ 3

Author(s):

SHIHUA LI ◽

YU-PING TIAN

Keyword(s):

Equilibrium Point ◽

Lyapunov Stability ◽

Closed Loop ◽

Invariant Set ◽

Linear Feedback ◽

Chua’S Circuit ◽

Chua's Circuit ◽

Linear Feedback Controller ◽

Simulation Results ◽

First Time

In this paper, we develop a simple linear feedback controller, which employs only one of the states of the system, to stabilize the modified Chua's circuit to an invariant set which consists of its nontrivial equilibria. Moreover, we show for the first time that the closed loop modified Chua's circuit satisfies set stability which can be considered as a generalization of common Lyapunov stability of an equilibrium point. Simulation results are presented to verify our method.

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Integration and Simulations of INS/GNSS System using the Approach of Carrier Phase Measurements

IAES International Journal of Robotics and Automation (IJRA) ◽

10.11591/ijra.v4i4.pp243-253 ◽

2015 ◽

Vol 4 (4) ◽

pp. 243

Author(s):

Khan Badshah ◽

Qin Yongyuan

Keyword(s):

Kalman Filtering ◽

Carrier Phase ◽

Closed Loop ◽

Position Estimation ◽

Integrated System ◽

Integer Ambiguity ◽

Font Size ◽

Phase Measurements ◽

Simulation Results ◽

Lever Arm Effect

This paper discusses the techniques of attitude, velocity ad position estimation from GNSS carrier phase measurements, and investigates the performance of the lower precision MEMS-based INS/GNSS system based on carrier phase measurements. Double differenced carrier phase measurements provide more accurate velocity and position estimation compared to code and Doppler measurements. However, integer ambiguity is required to be removed for precise positioning. Multiples antennae approach is used to derive the attitude information from carrier phase measurements in order to control the large initial misalignment angles for initialization of the integration process or to utilize during benign dynamics. Lever arm effect is considered to compensate for the separation of GNSS antenna and IMU location. The derived three GNSS observables are used to correct the INS through optimal Kalman filtering in a closed loop. Simulation results indicates the effectiveness of the integrated system for airborne as well as for land navigation vehicles. <div id="_mcePaste" class="mcePaste" style="position: absolute; left: -10000px; top: 0px; width: 1px; height: 1px; overflow: hidden;">This paper discusses the techniques of attitude, velocity ad position estimation from GNSS carrier phase measurements, and investigates the performance of the lower precision MEMS based INS/GNSS system based on carrier phase measurements. Double differenced carrier phase measurements provide more accurate velocity and position estimation compared to code and Doppler measurements. However, integer ambiguity is required to be removed for precise positioning. Multiples antennae approach is used to derive the attitude information from carrier phase measurements in order to control the large initial misalignment angles for initialization of the integration process or to utilize during benign dynamics. Lever arm effect is considered to compensate for the separation of GNSS antenna and IMU location. The derived three GNSS observables are used to correct the INS through optimal Kalman filtering in a closed loop. Simulation results indicates the effectiveness of the integrated system for airborne as well as for land navigation vehicles. </div>

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PI- Controlled PV Fed Fly Back Converter with Enhanced Dynamic Response

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.b1604.0982s1119 ◽

2019 ◽

Vol 8 (2S11) ◽

pp. 4031-4034

Keyword(s):

Steady State ◽

Dynamic Response ◽

Rise Time ◽

Closed Loop ◽

Input Voltage ◽

Pi Controller ◽

Open Loop ◽

Load Variations ◽

Simulink Model ◽

Step Down

Fly back converter is the most popular converter because of its simplicity, low part counts and isolation. It occupies less volume and it saves cost. Fly back converter steps up and step down the voltage with the same polarity. Open loop operation remains insensitive to the input voltage and load variations. Matlab Simulink model for Fly back converter is established using PI controller. Open loop Fly back converter system and closed loop fly back converter systems are simulated and their outcomes are compared. Comparison is done in terms of Rise time ,Settling time and steady state error

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ADAPTIVE CONTROL OF UNCERTAIN LORENZ SYSTEM USING DECOUPLED BACKSTEPPING

International Journal of Bifurcation and Chaos ◽

10.1142/s0218127404010035 ◽

2004 ◽

Vol 14 (04) ◽

pp. 1439-1445 ◽

Cited By ~ 4

Author(s):

S. S. GE

Keyword(s):

Adaptive Control ◽

Closed Loop ◽

Lorenz System ◽

Physical Property ◽

Asymptotic Convergence ◽

Closed Loop System ◽

Feedback Form ◽

Controlling Chaos ◽

Simulation Results ◽

The Lorenz System

In this letter, we reconsider the problem of controlling chaos in the well-known Lorenz system. Firstly, the difficulty in controlling the Lorenz system is discussed in the general strict-feedback form. Then, singularity-free adaptive control is presented for the Lorenz system with three key parameters unknown by exploiting the physical property of the system using decoupled backstepping design. The proposed controller guarantees the asymptotic convergence of the output and the boundedness of all the signals in the closed-loop system. Simulation results are conducted to show the effectiveness of the approach.

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Closed Loop Resonator Based Compact UWB Antenna with Single Notched Band Varying between WLAN and X-band for UWB Applications

Frequenz ◽

10.1515/freq-2019-0115 ◽

2020 ◽

Vol 74 (5-6) ◽

pp. 201-209

Author(s):

Mohammad Ahmad Salamin ◽

Sudipta Das ◽

Asmaa Zugari

Keyword(s):

Closed Loop ◽

Ground Plane ◽

Frequency Range ◽

Uwb Antenna ◽

Notched Band ◽

X Band ◽

Compact Size ◽

Simulation Results ◽

Uwb Applications ◽

Good Agreement

AbstractIn this paper, a novel compact UWB antenna with variable notched band characteristics for UWB applications is presented. The designed antenna primarily consists of an adjusted elliptical shaped metallic patch and a partial ground plane. The proposed antenna has a compact size of only 17 × 17 mm2. The suggested antenna covers the frequency range from 3.1 GHz to 12 GHz. A single notched band has been achieved at 7.4 GHz with the aid of integrating a novel closed loop resonator at the back plane of the antenna. This notched band can be utilized to alleviate the interference impact with the downlink X-band applications. Besides, a square slot was cut in the loop in order to obtain a variable notched band. With the absence and the existence of this slot, the notched band can be varied to mitigate interference of the upper WLAN band (5.72–5.82 GHz) and X-band (7.25–7.75 GHz) with UWB applications. A good agreement between measurement and simulation results was achieved, which affirms the appropriateness of this antenna for UWB applications.

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A New Controller of Stochastic Delay Systems

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.63-64.974 ◽

2011 ◽

Vol 63-64 ◽

pp. 974-977

Author(s):

Yun Chen ◽

Qing Qing Li

Keyword(s):

Time Delay ◽

Closed Loop ◽

Stochastic Systems ◽

Delay Systems ◽

Mean Square ◽

Closed Loop System ◽

Stochastic Delay ◽

Numerical Example ◽

Mean Square Stability ◽

Delay Dependent

By introducing an additional vector, a new delay-dependent controller is designed for stochastic systems with time delay in this paper. The presented controller is formulated by means of LMI, and it guarantees robust asymptotical mean-square stability of the resulting closed-loop system. Our result shows advantage over some existing ones, which is demonstrated by a numerical example.

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