This paper presents an advanced robust controller for the speed system of a switched reluctance motor (SRM) in the presence of nonlinearities, speed ripple, and external disturbances. It proposes that the adaptive fuzzy control is applied to regulate the motor speed in the outer loop, and the detector is used to obtain rotor detection in the inner loop. The new fuzzy logic tuning rules are achieved from the experience of the operator and the knowledge of the specialist. The fuzzy parameters are automatically adjusted online according to the error and its change of speed in the transient period. The designed detector can obtain the rotor’s position accurately in each phase module. Furthermore, a series of contrastive simulations are completed between the proposed controller and proportion integration differentiation controller including low speed, medium speed, and high speed. Simulations show that the proposed robust controller enables the system reduced by at least 3% in overshoot, 6% in rise time, and 20% in setting time, respectively, and especially under external disturbances. Moreover, an actual SRM control system is constructed at 220 V 370 W. The experiment results further prove that the proposed robust controller has excellent dynamic performance and strong robustness.

Breeze energy is a widely distributed renewable energy source in the natural world, but its efficient exploitation is very difficult. The conventional harvester with fixed arm length (HFA) has a relatively high start-up wind speed owing to its high and constant rotational inertia. Therefore, this paper proposes a harvester with a helix s-type vertical axis (HSVA) for achieving random energy capture in the natural breeze environment. The HSVA is constructed with two semi-circular buckets driven by the difference of the drag exerted, and the wind energy is transferred into mechanical energy. Firstly, as the wind speed changes, the HSVA harvester can match the random breeze to obtain highly efficient power. Compared with the HFA harvester, the power coefficient is significantly improved from 0.15 to 0.2 without additional equipment. Furthermore, it has more time for energy attenuation as the wind speeds dropped from strong to moderate. Moreover, the starting torque is also better than that of HFA harvester. Experiments showed that the HSVA harvester can improve power performance on the grounds of the wind speed ranging in 0.8–10.1 m/s, and that the star-up wind speed is 0.8 m/s and output peak power can reach 17.1 mW. In comparison with the HFA harvester, the HSVA harvester can obtain higher efficient power, requires lower startup speed and keeps energy longer under the same time. Additionally, as a distributed energy source, the HSVA harvester can provide a self-generating power supply to electronic sensors for monitoring the surrounding environment.

Traditional magnetic levitation planar micromotors suffer from poor controllability, short travel range, low interference resistance, and low precision. To address these issues, a distributed coil magnetically levitated planar micromotor with a gated recurrent unit (GRU)-extended state observer (ESO) control strategy is proposed in this paper. First, the structural design of the distributed coil magnetically levitated planar micromotor employs a separation of levitation and displacement, reducing system coupling and increasing controllability and displacement range. Then, theoretical analysis and model establishment of the system are conducted based on the designed distributed coil magnetically levitated planar micromotor and its working principles, followed by simulation verification. Finally, based on the established system model, a GRU-ESO controller is designed. An ESO feedback control term is introduced to enhance the system’s anti-interference capability, and the GRU feedforward compensation control term is used to improve the system’s tracking control accuracy. The experimental results demonstrate the reliability of the designed distributed coil magnetic levitation planar micromotor and the effectiveness of the controller.

For both magnets and coils are arranged in motor primary, short primary, and long secondary flux switching permanent magnet linear motor (FSPMLM) is extremely appropriate to long distance applications. A novel FSPMLM is developed to construct a feeding apparatus in this article. The magnetic field is analyzed by equivalent magnetic circuit (EMC), which indicates that the longitudinal end effect can be weakened by adjusting the width of the end-PMs. Then finite element analysis (FEA) and response surface methodology (RSM) are applied to optimize the force performance. The whole construction of the proposed FSPMLM feeding apparatus is designed and the prototype is manufactured. A commercial servo amplifier is used to control the prototype and the experiment setup is built to demonstrate the prototype performance. 500 mm feeding distance is conducted with the rated speed 1.5 m/s and the acceleration 10.0 m/s², which indicates the high speed and high acceleration capacity. Then 10 kg and 20 kg weights are loaded on the prototype with the speed 200 mm/s and 100 mm/s, respectively. Well force response performance is exhibited, and the position error is sufficient low. It can be seen that the proposed FSPMLM feeding apparatus can be employed competitively in various machine tools.

As both magnets and coils are arranged in the motor primary, a short primary long secondary flux switching permanent magnet linear motor (FSPMLM) is favorable to construct a feed system, especially for long distance, multi-axis applications. A novel FSPMLM with a complementary primary module and end-PM topology is proposed to directly drive a biaxial feed system, and the whole structure is presented. To consider the influence of temperature raise on motor performance, magnetic-thermal coupling finite element analysis is employed, and then, the motor dimensions are optimized by the response surface method. With the same 500 N rated force and 1.5 m/s rated speed of the two FSPMLMs, the biaxial prototype is fabricated. Considering the two-axis synchronization, the control system is constructed by using a commercial motion controller and servo drivers. Monoaxial and biaxial feeding experiments are carried out simultaneously. Both X and Y axes exhibit sufficient force capability for well dynamic response, and the positioning error is less than 0.14 mm. Biaxial diamond and circular trajectories are conducted, and the contour errors are less than 0.88 mm. It can be seen that the proposed FSPMLM feed system is featured with favorable performance and competitiveness for applying in various industrial applications.

In recent years, the fine particles suspended in the atmosphere, especially the particle size less than 10 $\mu \mathrm{m}$, have caused very adverse effects on the climate environment and human health. However, the current research on the causes of air pollution mainly focuses on human activities and weather conditions. Considering the weak magnetism and chargeability of atmospheric fine particles, this study proposed a new view that space electromagnetic radiation may affect the physical properties of fine particles. We first analyzed the dynamic characteristics of magnetic micro-particle in the electromagnetic environment, and built a simulation model in the COMSOL simulation software. Finally, based on the theoretical analysis and simulation results, we built an experimental verification system to evaluate the effects of electromagnetic radiation on the physical properties of micro-particle, and carried out a 30-day control experiment. The experimental results showed that the physical properties such as particle size distribution, mass concentration, and morphology of suspended fine particles in the atmosphere under electromagnetic radiation are significantly different from those under non-electromagnetic radiation environment. It can be inferred that the aggregation, fusion, and deposition of suspended particles in the atmosphere are closely related to the complex electromagnetic environment in space.