Simple Hysteresis Research Articles

A NOVEL MULTIPHASE BIDIRECTIONAL FLY-BACK CONVERTER TOPOLOGY IS APPLIED TO INDUCTION MOTOR DRIVE

Hybrid Electric Vehicle (HEV) is an emerging technology in the modern world because of the fact that it mitigates environmental pollutions and at the same time increases fuel efficiency of the vehicles. Bi-directional Fly – back Converter controls electric drive of HEV of high power and enhances its performance which is the reflection of the fact that it can generate Constant voltages. For hybrid electric vehicles, the batteries and the drive dc link may be at different voltages. The batteries are at low voltage to obtain higher volumetric efficiencies, and the dc link is at higher voltage to have higher efficiency on the motor side. Therefore, a power interface between the batteries and the drive’s dc link is essential. This power interface should handle power flow from battery to motor, motor to battery, external gen-set to battery, and grid to battery. This paper proposes a multi-power-port topology which is capable of handling multiple power sources and still maintains simplicity and features like obtaining high gain, wide load variations, lower output-current ripple, and capability of parallel-battery energy due to the modular structure. The scheme incorporates a transformer winding technique which drastically reduces the leakage inductance of the coupled inductor. The development and testing of a bidirectional fly-back dc–dc converter for hybrid electric vehicle is described in this paper. Simple hysteresis voltage control is used for dc-link voltage regulation. The simulation results are presented, and modeling the circuit by using MATLAB/SIMULINK Platform.

Hysteresis curves of a resistance spot welding transformer

PurposeThe aim of the paper is to provide a simple and reliable hysteresis model for prediction of magnetization curves of a resistance spot welding transformer (RSWT) core, operating in a wide range of flux densities and excitation frequencies.Design/methodology/approachThe hysteresis model considered in the paper is the T(x) description advanced by J. Takács. Three options to extend the model to the dynamic magnetization conditions are considered. The excitation conditions differ from those prescribed by international standards.FindingsThe quasi‐static Takács model combined with a fractional viscosity equation similar to that proposed by S.E. Zirka outperforms other considered options. The effect of eddy currents may be considered as a disturbance factor to the frequency‐independent quasi‐static hysteresis loop.Research limitations/implicationsThe combined approach yields in most cases a satisfactory agreement between theory and experiment. For highest frequency considered in the paper (1 kHz) excessive “heels” were observed in the modelled loops. This artifact may be reduced by the introduction of a more complicated relationship for the viscous term. Future work shall be devoted to this issue.Practical implicationsThe combined Takács‐Zirka model is a useful tool for prediction of magnetization curves of a RSWT core in a wide range of flux densities and excitation frequencies.Originality/valueThe usefulness of the Takács description has been verified in a practical application. The model is able to predict magnetization curves under non‐standard excitation conditions.

Precise positioning and active vibration isolation using piezoelectric actuator with hysteresis compensation

This article investigates precise positioning at the micrometer scale using piezoelectric actuators. A special focus is given to the rejection of ambient vibration disturbances. An original experimental setup composed of two superposed piezoelectric actuator stages is used to evaluate the performances of the proposed approach. The bottom one is devoted to the disturbance generation, whereas the upper one allows position tracking and active stabilization. The experimental dynamic and hysteretic characterizations of the top actuator are performed. Based on the identified dynamic model, a linear controller is designed. Its performances are improved with a hysteresis compensation method. Such methods usually imply either simple symmetrical hysteresis (e.g. General Maxwell Slip) or operators able to model asymmetric loops (e.g. Preisach) at the cost of more memory usage and computational time. In the present study, a previously published lightweight asymmetric operator hysteresis is successfully used for the first time within a piezoelectric positioning closed-loop control.

Hysteretic cyclic response of concrete columns reinforced with smooth bars

The application of smooth (plain) bars in reinforced concrete (RC) construction has been abandoned since the 1970s; however, there are many old reinforced concrete buildings in the world whose construction is based on this old style that are now in need of structural seismic rehabilitation according to the requirements of present day seismic rehabilitation codes. The focus of this study concerns the investigation of the hysteretic cyclic response of RC columns with smooth bars. The results of six column specimens having a variety of details for overlapping splices of longitudinal bars while experiencing two different levels of axial loads under cyclic loading reversals are presented. Through analysis of test observations and the obtained experimental results, it is attempted to clarify major aspects of hysteretic response for RC columns with smooth bars, from a seismic assessment point of view. The hysteretic force–drift responses of columns are deeply investigated and a new concept explaining the flag shape form of the hysteretic response is presented. Furthermore, the rocking response of columns is predicted with a new formulation that assumes an internal compression strut inside the column body as a consequence of rocking that originated from high base rotations. Finally, a simple hysteresis rule is proposed which is the result of considering the combination of two springs in parallel to provide the total hysteretic response as the summation of rocking hysteretic and bottom anchor (smooth bar) hysteretic responses.

Five-phase AC/DC/AC converter with pulse-width modulation rectifier

The paper presents an AC/DC/AC power electronic converter system with a five-phase two-level active rectifier and a five-phase two-level inverter with a DC-link. This is an extension of a three-phase active rectifier with two additional legs. This topology may find its application in five-phase variable speed generator such as wind electric generator system and in multi-phase electric drive systems. The front end converter has two control loops; the DC-link voltage control and the source side current control with controllable power factor operation. This paper discusses the multiphase active rectifier applications in multi-phase motor drive system. Simple hysteresis controllers are used to control the input from the source and output to the load currents (five-phase induction motor stator current). The validity of the control is validated using analytical and simulation approaches.

Five-Phase AC/DC/AC Converter with Pulse-Width Modulation Rectifier

The paper presents an AC/DC/AC power electronic converter system with a five-phase two-level active rectifier and a five-phase two-level inverter with a DC-link. This is an extension of a three-phase active rectifier with two additional legs. This topology may find its application in five-phase variable speed generator such as wind electric generator system and in multi-phase electric drive systems. The front end converter has two control loops; the DC-link voltage control and the source side current control with controllable power factor operation. This paper discusses the multiphase active rectifier applications in multi-phase motor drive system. Simple hysteresis controllers are used to control the input from the source and output to the load currents (five-phase induction motor stator current). The validity of the control is validated using analytical and simulation approaches.

A Single Sided Matrix Converter Drive for a Brushless DC Motor in Aerospace Applications

This paper describes a brushless dc (BLDC) drive with a single sided matrix converter (SSMC) for an electrohydrostatic actuation system in aerospace application. The use of an SSMC with a BLDC motor is novel and is used to achieve operation without a microprocessor. A simple hysteresis current control strategy is implemented to control motor torque. The multiphase SSMC provides high reliability and fault tolerance with the penalty of more power devices. A five-phase SSMC prototype is built. The experiment results are presented to verify the drive performance.

Estimation of the Instantaneously Dissipated Hysteresis Losses in Superconductors

Cables in superconducting magnets are subjected to field-dependent losses, i.e., induced interstrand and interfilament coupling losses, and superconductor hysteresis losses. For the two kinds of induced eddy currents, analytical and numerical models are available, allowing calculating the dissipated power under various operating conditions. For the losses stemming from the superconductor magnetization, the literature only gives formulas for the dissipated energy over closed excitation cycles. We derive an expression for the instantaneously dissipated hysteresis losses during an arbitrary ramp profile using a simplified geometry and hysteresis model. This allows estimating the losses dissipated in nonclosed excitation loops.

One Domain Wall Hysteresis Model for Spherical Grain

The high uniaxial magnetic anisotropy makes phases like Nd2Fe14B, Sm2Co17, SmCo5or BaFe12O19are very suitable as hard permanent magnetic materials. In the case of ferromagnetic materials, the global magnetostatic energy changes, according to the domain wall configuration. The simplest case to be studied is that of spherical grain with only one domain wall, in phases with uniaxial symmetry. The magnetostic energy in this system is calculated by means of Legendre polynomials. Studying the maximums and minimums of energy in this system, a simple hysteresis model can be developed. The model provides insight about the dependence of the coercive force on the grain size.

Magnetic recording in rocks

Charting the movement of tectonic plates or the evolution of a dynamo ultimately relies on the behavior of often imperfect mineral grains in Earth’s magnetic field.

Stable Adaptive Fuzzy Control with Hysteresis Observer for Three-Axis Micro/Nano Motion Stages

This paper considers the analytical dynamics with simplified Dahl hysteresis model for a three-axis piezoactuated micro/nano flexure stage. An adaptive controller with nonlinear dynamic hysteresis observer is proposed using Lyapunov stability theory. In the controller, a fuzzy function approximator with parameters update law is included to compensate for the identification inaccuracy, model uncertainty, and flexure coupling effects. Simulation results are used to demonstrate the control performance.

引張軸力領域を含む変動軸力と曲げを受けるノンスリップ型露出柱脚の復元力特性と簡易履歴モデル

An anchor-bolt-yield-type exposed column-base showed many kinds of resisting mechanism subjected to tensile axial force and bending. Such resisting mechanisms have large effect on the hysteresis of restoring force characteristics, and that hysteresis curve was complicated. The authors proposed type exposed column-base had very simple hysteresis curve, which due to improving slipphenomenon of anchor-bolt-yield-type exposed column-base.In this paper, an experimental study on proposed type exposed column-base subjected to variable axial forces including tension and cyclic bending moment were carried out, and to proposed hysteresis model. The following conclusions were drawn.1) The restoring force characteristics was simply compare anchor-bolt-yield-type.2) The hysteresis model showed good agreement with the experimental results for the axial force under the equation (12) value.

Generalized Prandtl–Ishlinskii operators arising from homogenization and dimension reduction

We consider rate-independent evolutionary systems over a physical domain Ω that are governed by simple hysteresis operators at each material point. For multiscale systems where ε denotes the ratio between the microscopic and the macroscopic length scale, we show that in the limit ε→0 we are led to systems where the hysteresis operators at each macroscopic point is a generalized Prandtl–Ishlinskii operator.

Why are some hysteresis loops shaped like a butterfly?

The contribution of this paper is a framework for relating butterfly-shaped hysteresis maps to simple (single-loop) hysteresis maps, which are typically easier to model and more amenable to control design. In particular, a unimodal mapping is used to transform simple loops to butterfly loops. For the practically important class of piecewise monotone hysteresis maps, we provide conditions for producing butterfly-shaped maps and examine the properties of the resulting butterflies. Conversely, we present conditions under which butterfly-shaped maps can be converted to simple piecewise monotone hysteresis maps to facilitate hysteresis compensation and control design. Examples of a preloaded two-bar linkage mechanism and a magnetostrictive actuator illustrate the theory and its utility for understanding, modeling, and controlling systems with butterfly-shaped hysteresis.

A Linear Mapping Hysteresis Model Based on Theory of Microscopic Polarization

In this paper, the underlying anhysteretic polarization is quantified through constitutive equations derived using Boltzmann statictics and Langevin model. The remanent polarization and the irreversible polarization are analyzed. A thermodynamic description of ferroelectric phenomena is proposed to address the coupling relations between electrical field and mechanical field by considering the series expansion of the elastic Gibbs energy function. A simple linear mapping hysteresis model based on theory of microscopic polarization is derived. In order to evaluate the effectiveness of the proposed model, a micro-positioning stage driven by the PZT in open-loop operation was used to test. The experimental results show that the proposed hysteresis model could precisely describe hysteresis phenomena. The fitting error is within 0.5%.

Direct Torque Control of Induction Machine based on Intelligent Techniques

Induction machine drive based on Direct Torque Control (DTC) allows high dynamic performance with very simple hysteresis control scheme. Conventional Direct Torque Control (CDTC) suffers from some drawbacks such as high current, flux and torque ripple, difficulties in torque as well as flux control at very low speed. In this paper, we propose two intelligent approaches to improve the direct torque control of induction machine; fuzzy logic control and artificial neural networks control. We carry out a detailed comparison study between direct torque fuzzy control (DTFC), direct torque neural networks control (DTNNC) and CDTC applied to switching select voltage vector. The theoretical foundation principle, the numerical simulation procedure and the performances of both methods are also presented.

Anisotropic Vector Hysteresis Model Using an Isotropic Vector Play Model

A simple anisotropic vector hysteresis model is developed to represent 2D weakly anisotropic vector hysteretic property. An isotropic vector play model is identified from azimuthally averaged vector property of anisotropic material. An anisotropy matrix is multiplied to the isotropic vector play model to represent anisotropy. Simulations for alternating and rotational flux conditions show that the anisotropy matrix improves the representation of vector hysteretic properties for a non-oriented silicon steel sheet.

Multiple stressors and regime shifts in shallow aquatic ecosystems in antipodean landscapes

Summary1. Changes in land management (land use and land cover) and water management (including extraction of ground water and diversion of surface waters for irrigation) driven by increases in agricultural production and urban expansion (and fundamentally by population growth) have created multiple stressors on global freshwater ecosystems that we can no longer ignore.2. The development and testing of conceptual ecological models that examine the impact of stressors on aquatic ecosystems, and recognise that responses may be nonlinear, is now essential for identifying critical processes and predicting changes, particularly the possibility of catastrophic regime shifts or ‘ecological surprises’.3. Models depicting gradual ecological change and three types of regime shift (simple thresholds, hysteresis and irreversible changes) were examined in the context of shallow inland aquatic ecosystems (wetlands, shallow lakes and temporary river pools) in southwestern Australia subject to multiple anthropogenic impacts (hydrological change, eutrophication, salinisation and acidification).4. Changes in hydrological processes, particularly the balance between groundwater‐dominated versus surface water‐dominated inputs and a change from seasonal to permanent water regimes appeared to be the major drivers influencing ecological regime change and the impacts of eutrophication and acidification (in urban systems) and salinisation and acidification (in agricultural systems).5. In the absence of hydrological change, urban wetlands undergoing eutrophication and agricultural wetlands experiencing salinisation appeared to fit threshold models. Models encompassing alternative regimes and hysteresis appeared to be applicable where a change from a seasonal to permanent hydrological regime had occurred.6. Irreversible ecological change has potentially occurred in agricultural landscapes because the external economic driver, agricultural productivity, persists independently of the impact on aquatic ecosystems.7. Thematic implications: multiple stressors can create multiple thresholds that may act in a hierarchical fashion in shallow, lentic systems. The resulting regime shifts may follow different models and trajectories of recovery. Challenges for ecosystem managers and researchers include determining how close a system may be to critical thresholds and which processes are essential to maintaining or restoring the system. This requires an understanding of both external drivers and internal ecosystem dynamics, and the interactions between them, at appropriate spatial and temporal scales.

Comparative performance of BESS and SMES in distribution network to improve power quality

The FACTS devices, like STATCOM, are becoming a part of the modern power system to improve the power system operation and power quality problems. Integrating the battery energy storage system (BESS)/superconducting magnetic energy storage (SMES) across the dc bus of the STATCOM can provide effective modulation of the real and reactive power. The dynamics of each of these differ because of their nature of energy storage. In this paper, comparative dynamic performances of these devices across the STATCOM are presented. The control strategy is proposed to integrate these devices to improve the active power management within the constraints of source supply to take the advantage of off-peak load condition. The simple hysteresis controller ensures the unity power factor and sinusoidal supply current. Proposed controller is designed to regulate the real and reactive power while keeping the dc bus voltage constant in BESS and SMES. Simulation is carried out using realistic power devices to study the dynamic performance of these schemes. The prototype results are given to validate the performance.

Multiphase Bidirectional Flyback Converter Topology for Hybrid Electric Vehicles

For hybrid electric vehicles, the batteries and the drive dc link may be at different voltages. The batteries are at low voltage to obtain higher volumetric efficiencies, and the dc link is at higher voltage to have higher efficiency on the motor side. Therefore, a power interface between the batteries and the drive's dc link is essential. This power interface should handle power flow from battery to motor, motor to battery, external genset to battery, and grid to battery. This paper proposes a multi-power-port topology which is capable of handling multiple power sources and still maintains simplicity and features like obtaining high gain, wide load variations, lower output-current ripple, and capability of parallel-battery energy due to the modular structure. The scheme incorporates a transformer winding technique which drastically reduces the leakage inductance of the coupled inductor. The development and testing of a bidirectional flyback dc-dc converter for hybrid electric vehicle is described in this paper. Simple hysteresis voltage control is used for dc-link voltage regulation. The experimental results are presented to show the working of the proposed converter.