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The purpose of this paper is to present a method for computing voltage spikes endured by the insulation of the first coils of high-temperature (HT°) synchronous machines fed by PWM inverters that deliver fast-fronted voltage pulses.

The transient state following each steep edge is computed by SPICE using the global high-frequency (HF) equivalent circuit of the motor winding. This equivalent circuit is automatically built using the proposed elementary coil model. Two inorganic HT° technologies are compared: the first one uses a round copper wire insulated by a thin ceramic layer and the second one is made with an anodized aluminum strip.

The winding made with an anodized aluminum strip, which has a higher turn-to-turn capacitance, yields a better voltage distribution between coils of the machine.

The elementary coil equivalent circuit is computed from impedance measurements performed on an elementary coil. Another starting point could be developed with an FE analysis to determine the parameters of the HF equivalent circuit, which would avoid the need for a prototype coil before the machine design.

For inorganic motors, the insulation layers have poorer electrical characteristics compared with standard organic ones. Therefore, the computation of voltage spikes distribution along the coils of each phase represents a major issue in the design of HT° machines.

The presented approach is a step toward the design of HT° (400-500°C) actuators fed by PWM inverters based on fast SiC electronic switches.

The purpose of this study is to propose a modeling method of the equivalent circuit for a new type of high-temperature superconducting partial-core transformer (HTS-PCT) made of ReBCO-coated conductors.

The modeling process is based on the “Steinmetz” equivalent circuit. The impedance components in the circuit are obtained by the calculations of the core losses and AC losses of the HTS windings by using theoretical methods. An iterative computation is also used to decide the equivalent resistances of the AC losses of the primary and secondary HTS windings. The reactance components in the circuit are calculated from the energy stored in the magnetic fields by finite element method. The validation of the modeling method is verified by experimental results

The modeling method of the equivalent circuit of HTS-PCT is valid, and an equivalent circuit for HTS-PCT is presented.

The equivalent circuit of HTS-PCT could be obtained by the suggested modeling method. Then, it is easy to analyze the characteristics of the HTS-PCT by its equivalent circuit. Moreover, the modeling method could also be useful for the design of a specific HTS-PCT.

The study proposes a modeling method of the HTS-PCT made of the second-generation HTS tapes, i.e. ReBCO-coated conductors.

The purpose of this paper is to highlight the pros and cons of different models of the European Union (EU)-style Rules of Origin (RoO) that could be chosen by negotiators for a future UK–EU Free Trade Agreement (FTA). It will also underline the impact that any choice would have on economic operators and certain criteria that should be evaluated before taking any decisions on the adoption of RoO.

The paper will describe three different RoO models that could be chosen by negotiators. For each of them, it analyses the pros and cons and the impact on economic operators.

The choice of a RoO would have an impact on future EU–UK trade relations. It will affect the utilization rate of the FTA as well as investment (and divestment) corporate strategies in the UK and EU.

The paper introduces different criteria to evaluate the impact of RoO that should be taken into consideration by negotiators. It emphasizes that RoO should be simple, predictable, coherent, IT compatible and easily adaptable.

An object‐oriented event‐driven immersive virtual environment is described for the creation of virtual labs (VLs) for simulating physical experiments. Discussion focuses on a number of aspects of the VLs, including interface devices, software objects, and various applications. The VLs interface with output devices, including immersive stereoscopic screen(s) and stereo speakers; and a variety of input devices, including body tracking (head and hands), haptic gloves, wand, joystick, mouse, microphone, and keyboard. The VL incorporates the following types of primitive software objects: interface objects, support objects, geometric entities, and finite elements. Each object encapsulates a set of properties, methods, and events that define its behavior, appearance, and functions. A “container” object allows grouping of several objects. Applications of the VLs include viewing the results of the physical experiment, viewing a computer simulation of the physical experiment, simulation of the experiment’s procedure, computational steering, and remote control of the physical experiment. In addition, the VL can be used as a risk‐free (safe) environment for training. The implementation of virtual structures testing machines, virtual wind tunnels, and a virtual acoustic testing facility is described.

This paper aims to present a novel energy-efficient saturated open-core fault current limiter (FCL) with special permanent magnet (PM) modules.

The special PM modules are used to drive the cores of FCL into a saturated state from different directions in the normal operation condition, reducing the DC current of the saturated open-core FCL. An equivalent magnetic circuit model of the saturated open-core FCL with PM modules is built to calculate the magnetic flux density in the cores of FCL. By applying the modified nodal approach on the circuit, the nonlinear equations of the magnetic circuit can be achieved. The Newton – Raphson method is used to solve the nonlinear equations. The model shows good accuracy verified by finite element simulation and a physical experiment.

Compared with the original saturated open-core FCL structure with PMs, the novel saturated open-core FCL structure can save 84% DC power. The physical experiment results show that the saturated open-core FCL has a good performance on limiting the fault current.

A novel saturated open-core FCL structure with PM modules is proposed in this paper. A physical model of the saturated open-core FCL structure with PM modules is manufactured and tested. About 84% DC power can be reduced by using the PM modules in this saturated open-core FCL, and it can save most of the cost of the saturated open-core FCL.

Presents a study of a bulk superconductor sphere placed in a uniform magnetic induction field b₀(t).

Adapts some macroscopic laws for the numerical simulation of its evolution. This evolution is determinated by the front tracking method (FTM).

The deduction of some consequences concerning hysteresis losses, and comparison to a direct method are done.

Helps to solve some complex three‐dimensional eddy current problems in industrial devices.

This paper aims to demonstrate the benefits of using different impeder materials for induction tube welding systems.

To show the difference in using various impeder materials, a new approach was taken to model tube welding systems in two and three dimensions. Three-dimensional (3-D) electromagnetic models were used to determine the current distribution along the weld vee as well as the permeability of the tube along the length of the welding system. Two-dimensional (2-D) coupled electromagnetic plus thermal models with rotational movement were used to determine the temperature distribution in the heat-affected zone.

Simulation results suggest upwards of 25 per cent system power savings when using a soft magnetic composite (SMC) impeder rather than the traditional ferrites.

There is currently a lack of experimental data to validate the models, but future work will include comparison of models to real-world trials.

When dealing with tube welding systems, there are possibilities to improve process efficiency or increase production quality and output by improving the impeder material.

While simulations of tube welding systems have been done previously, studies on improving impeder materials are rarely carried out. This paper brings to light possible improvements to be made to induction tube welding systems.