2,939 research outputs found
Study of power conditioning system of superconducting magnetic energy storage system
A Superconducting Magnetic Energy Storage System (SMES) can be utilized for the compensation of nonlinear and pulsating loads. In this paper a power conditioning system (PCS) is designed to achieve SMES to work as a shunt active power filter and power conditioner at the same time. Two Hysteresis band controllers have been implemented to obtain (i) a sinusoidal input source current in phase with fundamental component of line to neutral source voltage irrespective of the load conditions (ii) Charging and discharging of SMES under constant voltage control mode. DC link voltage is kept constant by DC/DC Bidirectional Converter and source current is controlled by Voltage Source Converter (VSC). The magnitude of reference source current is obtained by controlling the energy of SMES by using Fuzzy Logic Controller (FLC). As it is a nonlinear controller it gives better performance than previously used PI controller in parameter variations and load disturbances. Analysis of the circuit operation under Fuzzy controller is presented in detail. Simulation has been done in MATLAB/Simulink and results are presented demonstrating the feasibility of the proposed power conditioning system
Fundamentals and applications of spatial dissipative solitons in photonic devices : [Chapter 6]
We review the properties of optical spatial dissipative solitons (SDS). These are stable, self‐localized optical excitations sitting on a uniform, or quasi‐uniform, background in a dissipative environment like a nonlinear optical cavity. Indeed, in optics they are often termed “cavity solitons.” We discuss their dynamics and interactions in both ideal and imperfect systems, making comparison with experiments. SDS in lasers offer important advantages for applications. We review candidate schemes and the tremendous recent progress in semiconductor‐based cavity soliton lasers. We examine SDS in periodic structures, and we show how SDS can be quantitatively related to the locking of fronts. We conclude with an assessment of potential applications of SDS in photonics, arguing that best use of their particular features is made by exploiting their mobility, for example in all‐optical delay lines
High-performance motor drives
This article reviews the present state and trends in the development of key parts of controlled induction motor drive systems: converter topologies, modulation methods, as well as control and estimation techniques. Two- and multilevel voltage-source converters, current-source converters, and direct converters are described. The main part of all the produced electric energy is used to feed electric motors, and the conversion of electrical power into mechanical power involves motors ranges from less than 1 W up to several dozen megawatts
Nonlinear Systems
Open Mathematics is a challenging notion for theoretical modeling, technical analysis, and numerical simulation in physics and mathematics, as well as in many other fields, as highly correlated nonlinear phenomena, evolving over a large range of time scales and length scales, control the underlying systems and processes in their spatiotemporal evolution. Indeed, available data, be they physical, biological, or financial, and technologically complex systems and stochastic systems, such as mechanical or electronic devices, can be managed from the same conceptual approach, both analytically and through computer simulation, using effective nonlinear dynamics methods. The aim of this Special Issue is to highlight papers that show the dynamics, control, optimization and applications of nonlinear systems. This has recently become an increasingly popular subject, with impressive growth concerning applications in engineering, economics, biology, and medicine, and can be considered a veritable contribution to the literature. Original papers relating to the objective presented above are especially welcome subjects. Potential topics include, but are not limited to: Stability analysis of discrete and continuous dynamical systems; Nonlinear dynamics in biological complex systems; Stability and stabilization of stochastic systems; Mathematical models in statistics and probability; Synchronization of oscillators and chaotic systems; Optimization methods of complex systems; Reliability modeling and system optimization; Computation and control over networked systems
Emerging Power Electronics Technologies for Sustainable Energy Conversion
This Special Issue summarizes, in a single reference, timely emerging topics related to power electronics for sustainable energy conversion. Furthermore, at the same time, it provides the reader with valuable information related to open research opportunity niches
Emerging Power Electronics Technologies for Sustainable Energy Conversion
This Special Issue summarizes, in a single reference, timely emerging topics related to power electronics for sustainable energy conversion. Furthermore, at the same time, it provides the reader with valuable information related to open research opportunity niches
Advances in Control of Power Electronic Converters
This book proposes a list of contributions in the field of control of power electronics converters for different topologies: DC-DC, DC-AC and AC-DC. It particularly focuses on the use of different advanced control techniques with the aim of improving the performances, flexibility and efficiency in the context of several operation conditions. Sliding mode control, fuzzy logic based control, dead time compensation and optimal linear control are among the techniques developed in the special issue. Simulation and experimental results are provided by the authors to validate the proposed control strategies
Device modelling for bendable piezoelectric FET-based touch sensing system
Flexible electronics is rapidly evolving towards
devices and circuits to enable numerous new applications. The
high-performance, in terms of response speed, uniformity and
reliability, remains a sticking point. The potential solutions for
high-performance related challenges bring us back to the timetested
silicon based electronics. However, the changes in the
response of silicon based devices due to bending related stresses is
a concern, especially because there are no suitable models to
predict this behavior. This also makes the circuit design a
difficult task. This paper reports advances in this direction,
through our research on bendable Piezoelectric Oxide
Semiconductor Field Effect Transistor (POSFET) based touch
sensors. The analytical model of POSFET, complimented with
Verilog-A model, is presented to describe the device behavior
under normal force in planar and stressed conditions. Further,
dynamic readout circuit compensation of POSFET devices have
been analyzed and compared with similar arrangement to reduce
the piezoresistive effect under tensile and compressive stresses.
This approach introduces a first step towards the systematic
modeling of stress induced changes in device response. This
systematic study will help realize high-performance bendable
microsystems with integrated sensors and readout circuitry on
ultra-thin chips (UTCs) needed in various applications, in
particular, the electronic skin (e-skin)
Four-leg active power filter control with SUI-PI controller
Four-leg active power filter is considered one of the greatest vital active filters that are frequently used in industrial applications, especially those that need to be controlled in each individual phase. Also, to control the neutral current that created because of a lot of unbalanced and non-linear loads. In this paper, the used active filter was controlled by a proposed control method which can achieve simplicity and intelligence at the same time. The novelty of this paper is using the proposed controller with Four-leg active power filter. This controller relies on instantaneous reactive power theory, which used to create the required currents that are injected into the network via the used active filter to remove the problems created by unbalanced and non-linear loads. It is also maintained that the current source a pure sinusoidal wave. The system is implemented on MATLAB/Simulink. The simulation results proved the preference of the proposed controller than the conventional proportional-integration controller, where it reduced the percentage of total harmonic distortion for the current source
Interplay between charge trapping and polarization switching in BEOL-compatible bilayer Ferroelectric Tunnel Junctions
We here report a joint experimental and theoretical analysis of polarization switching in
ferroelectric tunnel junctions. Our results show that the injection and trapping of charge into the
ferroelectric-dielectric stack has a large influence on the polarization switching. Our results are relevant to the physical understanding and to the design of the devices, and for both memory and memristor
applications
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