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Magnetic hysteresis holds significant technical and physical importance in the design of electromagnetic components. Despite extensive research in this area, modeling magnetic hysteresis remains a challenging task that is yet to be fully resolved. The purpose of this paper is to study vector hysteresis play models for anisotropic ferromagnetic materials in a physical, thermodynamical approach.

In this work, hysteresis play models are implemented to interpret magnetic properties, drawing upon classical rate-independent plasticity principles derived from continuum mechanics theory. By conducting qualitative and quantitative verification and validation, various aspects of ferromagnetic vector hysteresis were thoroughly examined. By directly incorporating the hysteresis play models into the primal formulations using fixed point method, the proposed model is validated with measurements in a finite element (FE) environments.

The proposed vector hysteresis play model is verified with fundamental properties of hysteresis effects. Numerical analysis is performed in an FE environment. Measured data from a rotational single sheet tester (RSST) are validated to the simulated results.

The results of this work demonstrates that the essential properties of the hysteresis effects by electrical steel sheets can be represented by the proposed vector hysteresis play models. By incorporation of hysteresis play models into the weak formulations of the magnetostatic problem in the h-based magnetic scalar potential form, magnetic properties of electrical steel sheets can be locally analyzed and represented.

This paper aims to analyze the influence of welding-induced mechanical stress of a magnetic core material on the performance behavior of a permanent magnet excited synchronous machine (PMSM). Welding, interlocking, clinching and the use of adhesives are state-of-the-art packaging technologies used in the manufacturing of electrical machines. However, the packaging processes degrade the electromagnetic properties of the electric steel sheets, thereby decreasing the performance and achievable range of the electric vehicle.

In this paper, an approach that maps the local changes in magnetic properties due to welding induced stress with the stress values is developed. The welding process induces internal stress inside the steel sheet due to the diffusion of thermal energy into the sheets. Other effects are the changes in the micro structures of the steel sheets (grain sizes). These induced mechanical stresses lead to significant deterioration of the electromagnetic properties. They also lead to an increase in iron loss attributed to steel lamination.

A low speed (city), a high-speed (highway) and WLTC-c3 driving cycle will be used to analyze the effects of the induced stresses on the machine efficiency at the different operating conditions. A high-speed PMSM with a maximum speed of 26,000 min⁻¹ and maximum torque of 130 Nm is designed for this study.

The value of this study is in the development of a local varying modeling approach that analyses the influence of weld-induced stress on the performance of electrical machines. Its originality is evident in the mapping methodology. This will enable an application dependent improvement possibilities due to the understanding of the impact of weld-induced stress on the electromagnetic properties of weld-packaged core.

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 study is to model the global dynamic hysteresis properties with an improved Jiles–Atherton (J-A) model through a unified set of parameters.

First, the waveform scaling parameters β, λ_k and λ_c are used to improve the calculation accuracy of hysteresis loops at low magnetic flux density. Second, the Riemann–Liouville (R-L) type fractional derivatives technique is applied to modified static inverse J-A model to compute the dynamic magnetic field considering the skin effect in wideband frequency magnetization conditions.

The proposed model is identified and verified by modeling the hysteresis loops whose maximum magnetic flux densities vary from 0.3 to 1.4 T up to 800 Hz using B30P105 electrical steel. Compared with the conventional J-A model, the global simulation ability of the proposed dynamic model is much improved.

Accurate modeling of the hysteresis properties of electrical steels is essential for analyzing the loss behavior of electrical equipment in finite element analysis (FEA). Nevertheless, the existing inverse Jiles–Atherton (J-A) model can only guarantee the simulation accuracy with higher magnetic flux densities, which cannot guarantee the analysis requirements of considering both low magnetic flux density and high magnetic flux density in FEA. This paper modifies the dynamic J-A model by introducing waveform scaling parameters and the R-L fractional derivative to improve the hysteresis loops’ simulation accuracy from low to high magnetic flux densities with the same set of parameters in a wide frequency range.

The present study aimed to develop the competencies of 21st-century learners by considering the characteristics of the education element in the curricula.

The study employed a qualitative research design and a content analysis technique. The research population consisted of 20 curriculum design professors selected via a snowball sampling method until data saturation was reached. The research instrument was semistructured interviewing. The content validity of the interview questions was determined according to 5 curriculum design experts' opinions. Four credibility, transferability, dependability and confirmability criteria were used to increase the accuracy of qualitative data. The findings were analyzed using thematic analysis (structural-interpretive) through open, axial and selective coding.

Education characteristics in competency-based curricula were categorized into knowledge, skills, attitude and educational values. Knowledge includes pedagogical knowledge, content knowledge, pedagogical content knowledge and pedagogical technological knowledge; teaching skills include organization, facilitation, care and flexibility; educational attitudes consist of educational and pedagogical attitudes; and educational values include individual and group-social values.

The present research put three critical dimensions together: the competencies of the new-age learners from the perspective of the curriculum, which is the heart of the education process and is aimed at sustainable development, which is the priority of the countries today.

In collaboration with their home cities, universities increasingly develop courses in which students investigate urban sustainability challenges. This paper aims to understand how far-reaching the collaboration with urban stakeholders in these courses is and what students are meant to learn from the transdisciplinary pedagogies.

This research is designed as a qualitative multiple-case study into the intentions of transdisciplinary courses in which universities collaborate with their home cities: Delft University of Technology in Delft and Amsterdam Institute for Advanced Metropolitan Solutions in Amsterdam. The study compares the written intentions of eight courses in course descriptions with the ideal intentions that teachers describe in interviews.

First, seven of the eight investigated courses were designed for urban stakeholders to participate at a distance or as a client but rarely was a course intended to lead to a collaborative partnership between the city and students. Second, the metacognitive learning objectives, such as learning to deal with biases and values of others or getting to know one’s strengths and weaknesses in collaboration, were often absent in the course descriptions. Learning objectives relating to metacognition are at the heart of transdisciplinary work, yet when they remain implicit in the learning objectives, they are difficult to teach.

This paper presents insight into the levels of participation intended in transdisciplinary courses. Furthermore, it shows the (mis)alignment between intended learning objectives in course descriptions and teachers’ ideals. Understanding both the current state of transdisciplinarity in sustainability courses and what teachers envision is vital for the next steps in the development of transdisciplinary education.