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In astrodynamics, orbit cranking is usually referred to as an interplanetary transfer strategy that exploits multiple gravity-assist maneuvers to change both the inclination and eccentricity of the spacecraft osculating orbit without changing the specific mechanical energy, that is, the semimajor axis. In the context of a solar sail-based mission, however, the concept of orbit cranking is typically referred to as a suitable guidance law that is able to (optimally) change the orbital inclination of a circular orbit of an assigned radius in a general heliocentric three-dimensional scenario. In fact, varying the orbital inclination is a challenging maneuver from the point of view of the velocity change, so orbit cranking is an interesting mission application for a propellantless propulsion system. The aim of this paper is to analyze the performance of a spacecraft equipped with an Electric Solar Wind Sail in a cranking maneuver of a heliocentric circular orbit. The maneuver performance is calculated in an optimal framework considering spacecraft dynamics described by modified equinoctial orbital elements. In this context, the paper presents an analytical version of the three-dimensional optimal guidance laws obtained by using the classical Pontryagin's maximum principle. The set of (analytical) optimal control laws is a new contribution to the Electric Solar Wind Sail-related literature. [ABSTRACT FROM AUTHOR]

Currently, excessive AC loss in the rectangular winding motor used for electric vehicles poses a significant challenge, necessitating effective measures to suppress the losses. This paper focuses on the Prius IV motor, employing a finite element two-dimensional model established using JMAG software. The influence of conductor material and the number of rectangular winding layers on motor AC loss under various operating conditions is thoroughly analyzed. Maintaining a constant number of rectangular winding layers, aluminum (Al) conductors replace copper (Cu) conductors in 2-layer, 4-layer, 6-layer, and 8-layer configurations, respectively. AC losses are compared among motors with 4-layer, 6-layer, 8-layer, and 10-layer Cu rectangular windings, all having identical slot dimensions. Subsequently, the 10-layer Al conductor scheme is chosen to optimize motor design. The results demonstrate an average reduction in AC loss up to 59.24% after motor optimization, further reducing motor manufacturing costs. [ABSTRACT FROM AUTHOR]

The Internet of Things (IoT) is introduced in systems with electrical machines, such as in electric drive systems, wind energy generating systems, and small and special machines, to remote monitor and control the operation for data acquisition and analysis. These systems can integrate with the equipment and retrofit the existing installations. At the end of the control loops there are always motors, or actuators, of big or small ratings, of rotating or linear movements, electrical or nonelectrical, which must produce the motion. This article analyses selected aspects of research and applications of IoT-based control in electric drive systems and of wind energy conversion systems with induction machines. Various applications and study cases of control systems of electrical machines with IoT technology are described. With the IoT-based control of induction machine systems operators can remotely monitor parameters and obtain accurate real-time feedback during fast changing duty cycle operation. Thus, IoT creates multipurpose instruments in the remote control of induction machines. The paper offers a comprehensive analysis of IoT-based control applications in the field of induction machines, with technical details of design, construction, experimental testing, and prototyping, that are useful to energy engineering specialists in the sector of electric drives and wind energy conversion systems. [ABSTRACT FROM AUTHOR]

Using experiments by Sanya (18.3°N, 109.6°E) Incoherent Scatter Radar (SYISR) during 22 days, we first obtained the line‐of‐sight ion velocity in multiple directions, further calculated three‐dimensional vector velocity through least squares fitting, and subsequently derived northward neutral wind and electric fields from 150 to 500 km based on the momentum equation. In order to verify the reliability of the derived northward neutral wind and electric field, we used NCAR‐TIEGCM and HWM for comparative analysis. They had a good consistency in terms of diurnal variation and direction. The SYISR vertical ExB velocity during the daytime is larger than that of TIEGCM, and the direction reverses occur after 20:00 for both TIEGCM and SYISR. We further compared our wind data with that of ICON satellite. They showed a positive correlation of ∼0.62. We also used the ∆H method to verify our eastward electric field. They showed a roughly linear dependency, although the correlation coefficient is not very high. Plain Language Summary: In the low latitude ionosphere, neutral wind drives ions moving across the geomagnetic field line and generates electric field. Therefore, neutral wind and electric field are two key drivers in low latitude ionospheric dynamics. Monitoring both parameters is important for low latitude ionosphere investigation. However, measuring neutral wind and electric field, especially height profile in the F region, is very challenging and rare. In this paper, using the newly built Sanya Incoherent Scatter Radar, we have developed sophisticated algorithm to derive neutral wind and electric field from multiple beams SYISR measurements. Further evaluations show the data is reliable and therefore useful. Key Points: Northward neutral wind and electric field from 150 to 500 km are obtained using 22 days continuously SYISR observationsThe derived northward neutral wind and electric field are in good agreement with well‐known modelsThe results are further independently evaluated by ICON satellite and geomagnetism data [ABSTRACT FROM AUTHOR]

Electric Solar Wind Sails (E-Sails) are a new type of spacecraft propellantless propulsion system that gathers its energy from solar wind protons and is potentially useful for interplanetary missions. Although optimal interplanetary trajectories have been the subject of thorough research, the substantial variability of the solar wind necessitates the adoption of active guidance strategies, an area that has received significantly less scholarly attention. This paper proposes guidance algorithms for E-Sails based on Model Predictive Control (MPC), a modern control methodology based on online re-planning of the trajectory. To this end, first, properties of E-sail time-optimal orbits are studied applying Pontryagin's Minimum Principle, and then time-optimal orbits for missions to Mars and Jupiter are computed via direct transcription methods. Next, solar wind perturbations are modeled, posing a challenging saturation problem due to their high variability. Guidance strategies based on Shrinking Horizon and Receding Horizon Model Predictive Control (RHMPC) are developed, analyzed and compared using Monte Carlo simulations, successfully implementing MPC to E-sail guidance. Lastly, the RHMPC strategy is successfully tested with accurate historical solar wind data from the WSA-Enlil model. • Solar wind fluctuations implies need of guidance in E-sail interplanetary missions. • Optimal planning for E-sails is performed using direct and indirect methods. • Control saturation due to solar wind pressure is reduced by leaving control margins. • Model predictive control guidance methods are compared with Monte Carlo analysis. • Receding horizon strategy in tested with semi-empirical historical solar wind. [ABSTRACT FROM AUTHOR]

This article presents a detailed analysis of the electromagnetic force and vibration behavior of a new axial flux permanent magnet (AFPM) machine with a yokeless stator and interior PM rotor. Firstly, the configuration of an AFPM machine with a dual rotor and a sandwiched stator is introduced, including the structural design, fixation of the yokeless stator and segmented skew rotor structure. Then, the influence of anisotropic material and a fixed structure on stator modes is analyzed, including elastic modulus, shear model, the skew angle of slot and the thickness of stator yoke. Furthermore, a new non-equally segmented skew rotor structure is proposed and calculated for the reduction in vibration based on the multiphysics model. Three different segmented skew rotor schemes are compared to illustrate the influence of reducing vibration and noise. The predicted results show that the effect of the non-equally segmented skew rotor on reducing vibration is better than the other two schemes. Finally, a 120 kW AFPM motor is experimented with and the result matches well with the predicted data. The vibration performance of the AFPM motor with a dual rotor and sandwiched yokeless stator is revealed comprehensively. [ABSTRACT FROM AUTHOR]

China uses subsidies extensively to take a leading role in the global markets of green-tech products such as battery electric vehicles and wind turbines. Against the background of the current EU investigations into Chinese subsidies in these sectors, this article takes a careful look at the Chinese subsidy system and provides new data on direct government subsidies to leading Chinese producers of electric cars and wind turbines. Extensive government support has allowed Chinese companies to scale up rapidly, to dominate the Chinese market and to expand into foreign markets. The article concludes that the EU should use its strong bargaining power due to the single market to induce the Chinese government to abandon the most harmful subsidies. [ABSTRACT FROM AUTHOR]

Assessment of solar and solar wind parameters driving the ionosphere model is essential for prediction of the ionospheric weather. In the present paper impact of the different solar, interplanetary and geomagnetic parameters on the global electron content (GEC) during intense space weather storms is investigated. Hourly GEC values are calculated from JPL global maps of total electron content GIM-TEC from 1995 to 2023. The sample comprises 90 intense storms from 1995 to 2023 associated with monthly peak of the weighted accumulation of the geomagnetic Apo (τ, t) index exceeding 90 nT. The 27 day weighted accumulation of the solar sunspot numbers SSN2 (τ), solar radio flux F10.7 (τ), the solar hydrogen emission Lyman _ α (τ) and the composite magnesium MgII (τ) indices are explored as precursors of GEC enhancements. As distinct from the positive ionosphere storm, the solar wind speed Vsw , the solar wind electric field Ey , merging electric field Em and Apo (τ, t) indices proved to be effective as potential drivers of the negative GEC depletion. The positive and negative dGEC deviations from hourly GEC are produced by subtracting a quiet reference GECav averaged during 24h prior the storm normalized by GECav. The hourly storm profiles Vsw(t) , Em(t) , Ey(t) , Apo (τ, t), Dst(t) , GEC(t) and dGEC(t) were reduced by method of superposed epochs. The zero epoch t 0 = 0 was taken at the peak Apo* (τ, t 0) and the storm time lasted for 48h from −12h prior t 0 and 35h afterwards. The best correlation of the positive storm dGECp amplitude is obtained with MgII (τ) and the negative storm dGECn with E m * and Apo* (τ, t 0) which are used to derive characteristics of five key points of storm-time dGEC (t) model: 1 – onset of the storm profile t 1 = t(dGECp) ; 2 – the amplitude dGECp max and its time t 2 (dGECp max); 3 – the time of transition t 3 (dGEC = 0) from the positive to negative (±) GEC storm; 4 – minimum negative disturbance dGECn min and its time t 4 (dGECn min), 5 – the end of the storm profile t 5 (dGECn). Analytical model of dGEC (t) is derived with Epstein step functions fitting 5 key points. Deviations dGEC (t) are inverted to GEC (t) using quiet reference pre-storm GECav. The model is validated for three intense storms on 26–28 February, 23–25 March and 23–25 April 2023. The results show improvement of dGEC forecast with RMS error reduced from 45 to 80% compared to results produced by the international reference ionosphere−plasmasphere model IRI-Plas. • Accumulation SSN2(τ), F10.7(τ), Lyman-α(τ), MgII(τ) show the best correlation of MgII(τ) with positive GEC storm. • Sample 90 intense storms for 1995–2023 are reduced by superposing with zero epoch at Apo (τ, t) > 90 nT. • Solar wind merging electric field Em proved to be the best precursor for Apo (τ , t), Dst(t) and negative GEC storm. • dGEC (t) forecasting model with MGII (τ) and Em field precursors shows RMSE improved by 45–80% compared to IRI-Plas. [ABSTRACT FROM AUTHOR]

Rare earth elements (REEs) as Dysprosium (Dy) are critical elements for the fabrication of components in many green energy technologies, from electric vehicles to wind turbines. Consequently, there is an increasing interest in creating sustainable and effective materials for the recovery and recycling of these elements. Zeolite materials have demonstrated a high affinity and selectivity for REEs. Thus, this paper aims to study the use of a synthetic LTA zeolite functionalized with nanomagnetite for Dy absorption, including a complete characterization of the synthetic zeolite, the kinetics and the factors affecting the adsorption efficiency. The maximum adsorption capacity reaches a value around 35 mg of Dy per gram of zeolite. The results from the adsorption isotherms and kinetic study revealed a good agreement with both Langmuir and Temkin models and pseudo-second-order kinetics. Furthermore, the thermodynamic analysis suggests that the adsorption of Dy onto the zeolite is a spontaneous and favorable process. The findings from this work could provide insights into the design and optimization of zeolite-based processes for REE recovery and recycling, contributing to the development of a more sustainable and circular economy. [Display omitted] • LTA zeolite functionalized with nanomagnetite was obtained by hydrothermal method. • Characterization confirms morphology, structure and functionalization of the zeolite. • Zeolite was employed to recover dysprosium through an adsorption process. • The maximum adsorption capacity of the zeolite for Dy was approximately 35 mg g−1 • Functionalization allows for easy separation from liquid solution with a magnet. [ABSTRACT FROM AUTHOR]