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The data provided here is for the electromagnetic heating of magnetite under radio-frequencies. The data includes that from material characterisation, in-situ magnetometry, calorimetry, in-situ power absorption measurement and arc-tangent modelling results. The data is aligned to the figures in the research publication and is intended that future researchers can make their own analysis based upon our work. Further relevant documentation may be found in the following resources. Noble, J. P. P., Bending, S. J., Sartbaeva, A., Muxworthy, A. R., and Hill, A. K., 2021. A Novel In Situ High‐Temperature Magnetometry Method for Radiofrequency Heating Applications. Advanced Energy Materials, 12(1), 2102515. Available from: https://doi.org/10.1002/aenm.202102515. The data is collected using techniques described fully in the accompanying research article. The data follows the figure numbers from the paper which should make it easy to navigate.

With renewable energy an increasingly essential element in providing clean, abundant energy and combating climate change, wave energy presents an enormous untapped resource. Key to the challenges facing the industry are the high operation and maintenance costs associated with operating in offshore environments. A recent technological development that could address this issue is the magnetic gear. The magnetic gear allows for smaller and more efficient electrical machines while providing inherent protection to the drivetrain and requiring substantially reduced maintenance due to the contactless nature of operation. With magnetic gears now reaching a high technology readiness level there is a need to develop accurate and efficient design methods. This work looks at developing these methods, along with design tools, with a focus on application to wave energy devices. This work introduces the concept and operating principles of magnetic gears and gives a state of the art in the variations available. Following a discussion of design considerations and methodology, the tools developed in this work are applied in the design and development of two prototypes which are tested for a range of operating conditions followed by a critical analysis of the results.

As the automotive paradigm shifts towards electric, limited range remains a key challenge. Increasing the battery size adds weight, which yields diminishing returns in range per kilowatt-hour. Therefore, energy recovery systems, such as regenerative braking and photovoltaic cells, are desirable to recharge the onboard batteries in between hub charge cycles. While some reports of regenerative suspension do exist, they all harvest energy in a parasitic manner, and the predicted power output is extremely low, since the majority of the energy is still dissipated to the environment by the suspension. This paper proposes a fundamental suspension redesign using a magnetically-levitated spring mechanism and aims to increase the recoverable energy significantly by directly coupling an electromagnetic transducer as the main damper. Furthermore, the highly nonlinear magnetic restoring force can also potentially enhance rider comfort. Analytical and numerical models have been constructed. Road roughness data from an Australian road were used to numerically simulate a representative environment response. Simulation suggests that 10’s of kW to >100 kW can theoretically be generated by a medium-sized car travelling on a typical paved road (about 2–3 orders of magnitude higher than literature reports on parasitic regenerative suspension schemes), while still maintaining well below the discomfort threshold for passengers (<0.315 m/s 2 on average).

The recent emergence of wide-bandgap power transistors enables higher switching frequencies in electrical motor drives. Their full utilization from a system point of view requires quantification of the corresponding time-harmonic motor losses. As an initial step, this paper presents a unique study of stator losses for three different commercially available nonoriented silicon–iron steel grades (with lamination thicknesses 0.1, 0.2, and 0.3 mm). The investigations cover a wide frequency range (10–100 kHz) at different levels of dc bias (up to 1.6 T). Iron losses are identified from measurements on fully assembled stators deploying a novel technique. By utilizing fully assembled stators, no additional samples are required. Manufacturing influence is inherently incorporated. Results show that measured iron losses are twice as high at 10 kHz compared with Epstein test results, which emphasizes the need to incorporate manufacturing influence on iron losses at high frequencies. The level of dc bias is also observed to have a significant impact on iron losses (up to 30%). Even though thinner laminations are known for reducing iron losses, the reduction is much lower than anticipated in the studied frequency range due to skin effect. Using a 0.1-mm lamination gauge instead of 0.3 mm reduces losses by 50% at 10 kHz, while the same substitution at 100 kHz only reduces losses by 30%. Future work includes loss separation in complete converter-fed machines.

An investigation considering the efficiency gains of electrical pulse-shaping for a two-stage reluctance accelerator system has been undertaken. An optimum gross efficiency of (1.36 ± 0.02)% was achieved, amounting to an increase of (290 ± 20)% relative to the performance of an equivalent single-stage accelerator. The performance increase due to pulse-shaping for a two-stage setup was found to surpass that achieved for this single-stage setup in terms of both efficiency and velocity. This investigation highlights the potential of pulse-shaping methods to increase the feasibility and flexibility of electrical acceleration for a variety of practical applications. The intention of this paper was to exhibit the potential of reluctance acceleration technology in multi-stage, initially by using a two-stage system. Possible avenues for further investigation are proposed, to build upon the results of this study.

The synthesis of magnetic nanoparticles has been intensively investigated not only for their electrical, optical and magnetic properties but also for their various new technological applications, such as in the areas of biology and medicine. Exchange-spring magnets are nanocomposites that are composed of magnetically hard and soft phases that interact by magnetic exchange coupling. Such systems give a major advantage of combining the permanent magnetic field with magnetization hence rendering the mixture with many unique magnetic properties compared to traditional single-phase nano-magnets. However, one major current problem encountered is to generate the stable homogeneous mixed phase nano-composites with a narrow particle distribution. Thus, the new nanocomposites can give an optimum exchange coupling for applications. Here, we report the synthesis of exchange spring coupling of FePt/Fe3Pt nanocomposites by modified polyol process. The nanocomposite is deliberately placed in silica such that the treatment could offer advantages of further stabilizing and isolating the nano-magnets from interferences by their embedment in silica during annealing. As a result, tailoring of the silica encapsulated FePt-Fe3O4 in its L10 phase can be, for the first time, demonstrated.

The application of in situ nuclear magnetic resonance (NMR) to investigate batteries in real time (i.e., as they are cycling) provides fruitful insight into the electrochemical structural changes that occur in the battery. A major challenge for in situ static NMR spectroscopy of a battery is, however, to separate the resonances from the different components. Many resonances overlap and are broadened since spectra are acquired, to date, in static mode. Spectral analysis is also complicated by bulk magnetic susceptibility (BMS) effects. Here we describe some of the BMS effects that arise in lithium ion battery (LIB) materials and provide an outline of some of the practical considerations associated with the application of in situ NMR spectroscopy to study structural changes in energy materials.

Abstract: Direct drive Permanent Magnet Linear Generators (PMLGs) are used in energy converters for energy harvesting from marine waves. Greater reliability and simplicity can be achieved for Wave Energy Converters (WECs), by using direct drive machines linked to the power take-off device, in comparison with WECs using rotational generators combined with hydraulic or mechanical interfaces to convert linear to rotational torque. However, owing to the relatively low velocities of marine waves and the desire for significant energy harvesting by each individual unit, direct drive PMLGs share large permanent magnet volumes and hence, high magnetic forces. Such forces can generate vibrations and reduce the lifetime of the bearings significantly, which is leading to an increase in maintenance costs of WECs. Additionally, a power electronics converter is required to integrate the generator‘s electrical output to meet the requirements for connection to the national grid. This thesis is concerned mainly with the fundamental investigation into the use PMLGs for direct drive WECs. Attention is focused on developing several new designs based on tubular long stator windings topologies and optimisation for flat PMLGs. The designs are simulated as air- and iron-cored machines by means of Finite Element Analysis (FEA). Furthermore, a new power electronics control system is proposed to convert the electrical output of the long stator generators. Various wave energy-harvesting technologies have been reviewed and it has been found that permanent magnet linear machines demonstrate great potential for integration in WECs. The main reason is the strong exaltation flux provided by the high number of permanent magnets. Such flux, combined with design simplicity, can deliver high induced voltage as well as structural integrity. In the thesis, a flat single and double structured iron-cored PMLG is studied and optimised. Several magnetic force mitigation techniques are investigated and an optimisation is conducted. The optimisation is ...

With the global trend of carbon reduction, high-speed maglevs are going to use a large percentage of the electricity generated from renewable energy. However, the fluctuating characteristics of renewable energy can cause voltage disturbance in the traction power system, but high-speed maglevs have high requirements for power quality. This paper presents a novel scheme of a high-speed maglev power system using superconducting magnetic energy storage (SMES) and distributed renewable energy. It aims to solve the voltage sag caused by renewable energy and achieve smooth power interaction between the traction power system and maglevs. The working principle of the SMES power compensation system for topology and the control strategy were analyzed. A maglev train traction power supply model was established, and the results show that SMES effectively alleviated voltage sag, responded rapidly to the power demand during maglev acceleration and braking, and maintained voltage stability. In our case study of a 10 MW high-speed maglev traction power system, the SMES system could output/absorb power to compensate for sudden changes within 10 ms, stabilizing the DC bus voltage with fluctuations of less than 0.8%. Overall, the novel SMES power compensation system is expected to become a promising solution for high-speed maglevs to overcome the power quality issues from renewable energy.