A novel fault integration method is proposed in this paper for manufacturing system models given in the form of timed colored Petri nets. The faults are assumed to have a stochastic nature and are represented in the f...
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ISBN:
(纸本)9789077381861
A novel fault integration method is proposed in this paper for manufacturing system models given in the form of timed colored Petri nets. The faults are assumed to have a stochastic nature and are represented in the form of transitions firing in stochastic way with known fault probabilities in the system model. A novel fault effect propagation method was also developed, that can be used to compute the probabilities of the possible faulty and non-faulty intermediate and final states of the system using the probabilities of faults and the occurrence graph. The faultless and fault containing models were implemented in CPNTools both for non-timed and timed cases. A software module was also developed for the proposed probabilistic fault propagation analysis. The proposed methods and tools were demonstrated using a simple case study.
In addition to simplicity, the DTC of the IM allows a good torque control in steady-state and transient operating conditions. However, high torque ripple is produced, which is reflected in speed estimation responses. ...
In addition to simplicity, the DTC of the IM allows a good torque control in steady-state and transient operating conditions. However, high torque ripple is produced, which is reflected in speed estimation responses. It also increases acoustical noise and makes the voltage source inverter operated in high and variable switching frequency, requiring a high sampling frequency. In this paper, a simple effective ANN-based DTC of the induction machine is proposed. Neural networks with a simple architecture are designed and implemented in influential points of the direct torque control block of the three phase induction machine in order to improve its dynamic performance while preserving the DTC structure simplicity as much as possible. In particular, this paper proposes to reduce, on the one hand, the torque ripple and commutation frequency. Neural comparators are used to select the appropriate bandwidth for the torque and flux hysteresis controllers. Their aim is to optimize the ripple level in the developed torque and flux. On the other hand, a neural speed controller is designed in order to improve the system ability to respond rapidly to changes in process variables and mitigate the effects of external perturbations. The performance of the proposed control are tested in simulation and highlighted by comparing to the conventional DTC control based on conventional hysteresis comparators and conventional PI speed controller. The obtained results show the feasibility and good performances of the proposed control.
In industrial automation software controls systems whose failure can be critical and expensive. Testing this software is very crucial but so far done manually, an expensive and not very thorough method. Model-based te...
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This paper presents a shunt active power filter (SAPF) topology, based on the concept of a transformer with open-end winding (OEW), for reactive power and harmonic compensations employed in three-phase four wire (3P4W...
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This paper presents a shunt active power filter (SAPF) topology, based on the concept of a transformer with open-end winding (OEW), for reactive power and harmonic compensations employed in three-phase four wire (3P4W) systems under balanced and unbalanced conditions. The proposed system uses two independent dc-links and two independent converters series connected through transformers. Complete system control, including PWM technique, is developed and a comparison between the proposed SAPF and conventional one is presented as well. Simulation and experimental results are provided to validate the theoretical approach.
The aim of this work is to present an entropy-like Lyapunov function based dynamic feedback design technique for quasi-polynomial and Lotka-Volterra systems. It is shown, that the dynamic feedback design problem is eq...
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This paper proposes three dynamic voltage restorer (DVR) topologies. Such configurations are able to compensate voltage sags/swells in three-phase four-wire (3P4W) systems under balanced and unbalanced conditions. The...
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ISBN:
(纸本)9781479957774
This paper proposes three dynamic voltage restorer (DVR) topologies. Such configurations are able to compensate voltage sags/swells in three-phase four-wire (3P4W) systems under balanced and unbalanced conditions. The proposed systems in this work use two independent dc-links. The complete control system, including the PWM technique, is developed and comparisons between the proposed configurations and a conventional one are performed. Simulation and experimental results are provided to validate the theoretical approach.
The aim of this work is to present an entropy-like Lyapunov function based dynamic feedback design technique for quasi-polynomial and Lotka-Volterra systems. It is shown, that the dynamic feedback design problem is eq...
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The aim of this work is to present an entropy-like Lyapunov function based dynamic feedback design technique for quasi-polynomial and Lotka-Volterra systems. It is shown, that the dynamic feedback design problem is equivalent to the feasibility of a bilinear matrix inequality. The problem is also formulated as a control Lyapunov function based feedback design when the Lyapunov function parameters are given, the solution of this problem can be obtained by solving a linear matrix inequality. The developed method is illustrated on a simple numerical example.
In case that a monitoring supervisory system is deployed, then system administrators mostly know about an arisen problem almost immediately. They have it precisely localized and they can it quickly remove. In most cas...
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In case that a monitoring supervisory system is deployed, then system administrators mostly know about an arisen problem almost immediately. They have it precisely localized and they can it quickly remove. In most cases then it is not necessary to negotiate with a user who may not be an expert in information technology. Of course, deployment of a monitoring system sharply reduces the time of availability and reduces damages which can be consequently caused.
This paper studies feedback stabilization of a linear time-invariant (LTI) discrete-time system with information constraints in the input channels, described by additive white Gaussian noise (AWGN). A signal-to-noise ...
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ISBN:
(纸本)9781479913329
This paper studies feedback stabilization of a linear time-invariant (LTI) discrete-time system with information constraints in the input channels, described by additive white Gaussian noise (AWGN). A signal-to-noise ratio (SNR) constraint model is adopted in studying its communication capacity limits. Upper and lower bounds of the least capacity are derived for feedback stabilization in both state feedback and output feedback control of multi-input/multi-output (MIMO) systems.
The bag of visual words model (BoW) and its variants have demonstrate their effectiveness for visual applications and have been widely used by researchers. The BoW model first extracts local features and generates the...
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