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The purpose of this paper is to describe an effective method to eliminate or substantially reduce the modulation harmonics due to saturation and inter‐modulation for sensorless speed control induction motor drives at low and zero speed with high loads using artificial neural networks (ANNs).

In this paper, the separation of the saturation signal, the slotting signal, and the inter‐modulation signal components in squirrel cage induction machines operating at low and zero frequency using ANNs has been experimentally implemented and measurement results are given.

The measurement results show the advantages of the application of the proposed technique at low and zero speed sensorless control even at high load levels.

The paper describes an effective method of eliminating or reducing modulation harmonics in induction motor drives.

Double rotor induction machine (DRIM) is a particular type of induction machine (IM) that has been introduced to improve the parameters of the conventional IM. The purpose of this study is to propose a dynamic model of the DRIM under saturated and unsaturated conditions by using the equations obtained in this paper. Also, skin and temperature effects are considered in this model.

First, the DRIM structure and its performance will be briefly reviewed. Then, to realize the DRIM model, the mathematical equations of the electrical and mechanical part of the DRIM will be presented by state equations in the q-d axis by using the Park transformation. In this paper, the magnetizing fluxes saturation is included in the DRIM model by considering the difference between the amplitudes of the unsaturated and saturated magnetizing fluxes. The skin and temperature effects are also considered in this model by correcting the rotor and stator resistances values during operation.

To evaluate the effects of the saturation and skin effects on DRIM performance and validate the model, the machine is simulated with/without consideration of saturation and skin effects by the proposed model. Then, the results, including torque, speed, stator and rotor currents, active and reactive power, efficiency, power factor and torque-speed characteristic, are compared. In addition, the performance of the DRIM has been investigated at different speed conditions and load variations. The proposed model is developed in Matlab/Simulink for the sake of validation.

This paper presents an understandable model of DRIM with and without saturation, which can be used to analyze the steady-state and transient behavior of the motor in different situations.

This work aims to improve upon the linearity of integrated CMOS current sensors used in switch mode power supply topologies, using a low-cost and low-voltage (less than 1.2 V) CMOS technology node. Improved sensor accuracy contributes to efficiency in switched supplies by reducing measurement errors when it is integrated with closed-loop control.

Integrated current-sensing methods were investigated and CMOS solutions were prioritized. These solutions were implemented and characterized in the desired process and shortcomings were identified. A theoretical analysis accompanied by simulated tests was used to refine improvements which were prototyped. The current sensor prototypes were fabricated and tested.

Measured and simulated results are presented which show improved linearity in current sensor outputs. Techniques borrowed from analog amplifier design can be used to improve the dynamic range and linearity of current-steered CMOS pairs for measuring current. A current sensor with a gain of 5 V/A operating in a 10 MHz switch mode supply environment is demonstrated.

This paper proposes an alternative approach to creating suitable bias conditions for linearity in a SenseFET topology. The proposed method is compact and architecturally simple in comparison to other techniques.

In this article, we develop and advance an understanding of institutions as multimodal accomplishments. We draw on social semiotics and the linguistic concept of metafunctions to establish the visual as a specific mode of meaning construction. In addition, we make semiotic modes conducive to institutional inquiry by introducing the notion of distinct “modal registers” – specialized configurations of linguistic signs within a particular mode that are adapted and applied in the reproduction of institutions or institutional domains. At the core of our article, we operationalize metafunctions to develop methodology for the analysis of visual registers. We illustrate our approach with data from Corporate Social Responsibility (CSR) reporting in Austria.

The purpose of this paper is to reflect on pedagogical strategies which support the teaching of critical analysis of visual and multimodal texts in a tertiary-level course for Arts students.

The paper describes strategies which focus on developing students’ abilities to express interpretive critique, as opposed to mere description. These strategies give students strong scaffolding towards success in their interpretive writing. The course in question is a tertiary-level Arts course which teaches Kress and van Leeuwen’s (2006) approach to “reading images” in relation to contemporary media texts. The basic structure of the course is described, along with the macro steps which underpin the pedagogy. Examples of highly successful and less successful student writing are compared to reveal the key components of effective interpretive answers.

In addition to the normal expectations regarding essay structure and style, and in addition to mastery of the technicality of the course, successful and less successful student writing depends on their mastery of a specific set of moves within the essay. These moves integrate textual observations with clear explanations and a strong relation to interpretation.

While the course and strategies discussed are for tertiary-level students, the strategies described are adaptable to primary and secondary levels also. Multimodal texts are an integral part of the English curriculum, and all teachers need to explore strategies for enabling their students’ critical engagement with such texts.

Visual and multimodal texts are an exciting and also challenging part of English curricula, and new analytical frameworks and pedagogical strategies are needed to tackle these texts. In particular, the gap between simply describing visual resources (applying the tools) and critical analysis (using the tools) is vast, and specific pedagogical strategies are needed to help students develop the necessary interpretive language.

This paper seeks to propose a methodological tool for arts marketing, arguing that traditional approaches are not as effective as the newly developed visibility/involvement model in assessing the quality of a cultural organization's marketing strategy.

The innovative model evaluates art galleries' promotion materials combining their local, visual, and textual dimensions of meaning, drawing on three different theoretical and methodological areas of thought: critical discourse analysis, systemic functional analysis, and mediated discourse analysis.

The visibility involvement model can be applied by cultural organizations to discern their key audience, and thus, their communicative focus. It is also the foundation of practical recommendations to enhance a gallery's marketing strategy to either deepen or broaden their audience.

While the paper investigates the predominant meaning dimension of different groups of promotional materials, it does not investigate all relevant dimensions. Although, the proposed model provides insights into the quality of the art galleries' marketing activities, it only provides a rather vague distinction between the degrees of visibility and required involvement. This paper does also not account for the usability of the model for organizations outside the cultural sector.

The innovation of the newly developed model lies in the combination of these dimensions coming from three theoretical and methodological areas of thought: mediated discourse analysis, systemic functional analysis, and critical discourse analysis.

The purpose of this paper is to evaluate the conditions in which a saturation of the common mode (CM) choke might appear to be essential for proper design of the CM voltage filters. This paper presents a method for the determination of a CM choke flux density produced by multilevel inverters with carrier‐based modulations.

The proposed combination of secant and tangent methods allows efficient and high‐resolution determination of the CM voltage waveforms produced at the output of the multilevel inverters with commonly used carrier‐based modulations.

The presented results show that the application of a five‐level inverter with specific modulation causes a decrease of the maximum flux density, down to 15 per cent of the maximum level of the flux density reached in a two‐level inverter. The proposed, dedicated approximation method provides an accuracy of the root estimation better by about three orders for a comparable number of the function calls in comparison with Brent's method.

The presented theoretical evaluations make possible the determination of the maximum expected value of the flux density produced by multilevel inverters with various types of carrier‐based modulations, which allows a reduction in dimensions, weight and cost of CM chokes applied in CM voltage compensators.

In the paper, the new formulas that describe the placement of triangular carrier functions for commonly used multilevel inverters have been presented. In order to avoid accumulation of the estimation error, during determination of the CM voltage time integral, a dedicated, efficient method of roots approximation has been developed.

The large signal modulation response of a 1.3 μm InGaAsP 4‐well laser of the Fabry–Perot type is investigated. The current density is assumed to take the form J = J_O+J_M sin(ωt) where J_O is the steady state current density above threshold and J_M is allowed to take values such that the modulation depth, m, may not satisfy the condition m<< 1. The time evolution of the photon density shows that the output power may be sinusoidal when m<< 1, i.e. small signal modulation, low and very high frequencies. At intermediate frequencies, in the gigahertz range, the output power is far from sinusoidal and may show the characteristic oscillations due to the large‐signal transients. The resonance frequency is seen to decrease as the modulation depth increases, the worst case being when the nonlinear saturation effects are not included.

The purpose of this paper is to propose a new method that allows to compare the magnetic pressures of different pulse width modulation (PWM) strategies in a fast and efficient way.

The voltage harmonics are determined using the double Fourier integral. As for current harmonics and waveforms, a new generic model based on the Park transformation and a dq model of the machine was established taking saturation into consideration. The obtained analytical waveforms are then injected into a finite element software to compute magnetic pressures using nodal forces.

The overall proposed method allows to accelerate the calculations and the comparison of different PWM strategies and operating points as an analytical model is used to generate current waveforms.

While the analytical expressions of voltage harmonics are already provided in the literature for the space vector pulse width modulation, they had to be calculated for the discontinuous pulse width modulation. In this paper, the obtained expressions are provided. For current harmonics, different models based on a linear and a nonlinear model of the machine are presented in the referenced papers; however, these models are not generic and are limited to the second range of harmonics (two times the switching frequency). A new generic model is then established and used in this paper after being validated experimentally. And finally, the direct injection of analytical current waveforms in a finite element software to perform any magnetic computation is very efficient.

The purpose of this paper is to present an improved conformal mapping (ICM) method that simultaneously considers the influence of relative recoil permeability of PMs, the armature reaction, the stator slotting, and the magnetic saturation on determination of the PM operating point in its different parts.

The ICM method is a time-effective method that considers the magnetic saturation by suitable increments in air-gap length under each tooth and also the width of slot openings. In this paper, the analytical and numerical conformal mappings such as the Schwarz-Christoffel (SC) mapping are used for magnetic field analysis due to the permanent magnets and the armature reaction in one slotted air gap. The field solution in the slotted air gap is obtained through the modulation of field solution in one slotless air-gap using the complex air-gap permeance.

The ICM method can consider the magnetic saturation in different electric loadings, and also the variation of PM operating points in its different parts.

The ICM method is applied to one surface mounted permanent magnet (SMPM) motor and is verified by comparing with the corresponding results obtained through finite element method (FEM), and frozen permeability finite element method (FP-FEM).

This paper presents an ICM method with a new technique for saturation effect modeling, which can be used to separate and calculate the on-load components of air-gap field and torque.