Shuhua Fang

Bio: Shuhua Fang is an academic researcher from Southeast University. The author has contributed to research in topics: Magnet & Stator. The author has an hindex of 21, co-authored 151 publications receiving 1422 citations.

A General Analytical Model of Permanent Magnet Eddy Current Couplings

Abstract: An improved practical two-dimensional model for the analytical calculation of the magnetic field distributions in permanent magnet (PM) eddy current couplings is presented to obtain the torque characteristics. By establishing the Cartesian coordinate reference system on the rotating conductor, the PM region is treated as a source of traveling wave magnetic field and then the multi-layer boundary value problem is solved. The formulation for the magnet blocks, the eddy current and saturation effects in the solid secondary back iron, and the equivalence relationships between typical PM shapes, are all reasonably taken into account. Calculation results produced by the proposed analytical model are compared with those from the nonlinear finite element method and experimental measurement.

Overview of wind power generation in China: Status and development

Abstract: Wind power generation has increased rapidly in China over the last decade. In this paper the authors present an extensive survey on the status and development of wind power generation in China. The wind resource distributions in China are presented and assessed, and the 10 GW-scale wind power generation bases are introduced in details. The domestic research status of main components of WP system is then elaborated, followed by an evaluation of the wind power equipment manufacturers. Finally, the outlook for the development of the wind power utilization in China is presented.

A Variable-Flux Hybrid-PM Switched-Flux Memory Machine for EV/HEV Applications

Abstract: In this paper, a novel topology of hybrid-permanent-magnet switched-flux memory machine (HPM-SFMM) is proposed, which is characterized by a conventional SFPM machine with embedded “V”-shaped Al-Ni-Co magnet poles. The proposed machine combines the distinct synergies of torque enhancement in neodymium–iron–boron (NdFeB) PM and flux variability in aluminum–nickel–cobalt (AlNiCo) PM. By changing the magnetization directions of Al–Ni–Co magnets, the wide-speed-range high-efficiency operation can be readily achieved, which is highly favorable for automotive applications. The configuration and operating principle of the machine are first described, and the combination of stator/rotor pole numbers is optimized. In addition, the torque density/flux adjusting capability as the functions of dual-magnet dimensions are analytically derived. The magnet hybridizing proportion is optimized in order to achieve a favorite tradeoff between flux adjusting range and torque density improvement. Then, the electromagnetic performance of the proposed HPM-SFMM is investigated. Finally, a 12/14-stator/rotor pole prototype is fabricated to experimentally verify the analysis.

A Novel Dual-Stator Hybrid Excited Synchronous Wind Generator

Abstract: This paper presents a novel dual-stator hybrid excited synchronous wind generator and describes its structural features and operation principle. The no-load magnetic fields with different field currents are computed by 3-D finite-element method. Static characteristics, including the flux-linkage and EMF waveforms of stator windings, and inductance waveforms of armature windings and field winding, are analyzed. The simulation results show that due to the dual-stator structure, the air-gap magnetic flux can be easily controlled, while the output voltage can be increased effectively. Tests are performed on the prototype machine to validate the predicted results, and an excellent agreement is obtained.

Analysis of a Novel Switched-Flux Memory Motor Employing a Time-Divisional Magnetization Strategy

Abstract: This paper presents a novel switched-flux memory motor (SFMM) by artfully incorporating the flux-mnemonic concept into the conventional switched-flux permanent magnet machine. The magnetic susceptibility of AlNiCo PM provides the flexible online controllability of air-gap flux by imposing a transient current pulse. To uniformize magnetization levels of PMs, a time-divisional magnetization strategy (TDMS) is proposed. Due to the uniqueness of hysteresis nonlinearity and instability regarding AlNiCo PM operating point, the time-stepping finite element method (TSFEM) dynamically coupled with a nonlinearity-involved parallelogram hysteresis model (NIPHM) of AlNiCo PM is performed to investigate the electromagnetic performance of the proposed SFMM. The results derived from the combinative algorithm verifies the flux-adjustable capability of the proposed motor equipped with TDMS and the validity of the proposed NIPHM.

Polymer-Based Magnetoelectric Materials

Abstract: Polymer-based magnetoelectric (ME) materials are an interesting, challenging and innovative research field, that will bridge the gap between fundamental research and applications in the near future. Here, the current state of the art on the different materials, the used configurations for the development of sensors and actuators, as well as the main values of the ME coupling obtained for the different polymer-based systems are summarized. Further, some of the specific applications that are being developed for those polymer-based ME materials are addressed as well as the main advantages and remaining challenges in this research field.

Multimode Optimization Design Methodology for a Flux-Controllable Stator Permanent Magnet Memory Motor Considering Driving Cycles

Abstract: In this paper, a multimode design method is proposed for motor design under multiple operation conditions. Based on the driving cycles in electric vehicles, five typical operation conditions and the corresponding five driving modes are determined for the multimode design. To investigate the method conveniently, a flux controllable stator permanent magnet (SPM) memory motor is selected and taken as a design example. In the design process, by using the sensitivity analysis method, the significance of the parameters in various driving modes are evaluated effectively. Based on the motor driving demands, the whole optimization design is divided into three steps, where different optimization method is applied in each step. To verify the feasibility of the multimode design method, the operation performances of the motor in different driving modes are investigated in detail. Finally, a prototype motor is built and tested. Both the simulation and experimental results reveal that the proposed design method can offer an effective design optimization for the flux-controllable SPM memory motor, where multimode operations are indispensable.

Stability and Relaxation Mechanisms of Citric Acid Coated Magnetite Nanoparticles for Magnetic Hyperthermia

Abstract: Fil: de Sousa, Maria Elisa. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - La Plata. Instituto de Fisica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Fisica La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Fisica; Argentina

China's energy status: a critical look at fossils and renewable options.

Abstract: China relies heavily on fossil fuels to keep the wheel of its huge economy running. Fossil fuels are however not a sustainable energy source due largely to their environmental footprint and supply insecurity. These concerns have necessitated the need for alternative energy sources that are both renewable and environmentally friendly. This policy direction is in line with the Kyoto protocol that constrained countries to follow certain energy consumption pattern that encourages the use of less carbon intensive energy sources. In line with this protocol, China has over the years adopted the use of various renewable energy sources including solar, wind, marine, as well as hydropower. This commitment by the Chinese government has yielded significant result over the years. Notably, between 2014 and 2015, wind and solar energies were responsible for 25.4% of electrical energy produced in China. However, enabling laws to support the optimum consumption of these energies has not been provided, thereby resulting in a serious setback. In spite of the increased production in renewable energies, biofuels have contributed only marginally to the entire growth. Biofuels are very important considering the contribution of the transport sector to carbon emissions. Although there are ethical issues associated with current biofuels due to energy-food nexus, this review submits that algal biofuel could serve as an alternative. To this end, there is urgent need for the government to put in place laws and policies that will support not only production but also consumption of renewables, including algal biofuel, so that dependence on coal and other fossil fuels can be further reduced. This will not only reduce the country's dependence on oil import which is currently at 59.4% but greatly reduce greenhouse gas (GHG) emissions.