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Owing to the definite merits of high-efficiency and high-power density, the permanent-magnet (PM) brushless machines have been dominating the high-performance industrial applications. However, the problems of high PM material cost, fluctuating supply of rare-Earth materials and ineffective PM flux control have hindered the widespread applications of the PM brushless machines. In recent years, many attentions have been shifted to the magnetless candidates, while the focuses are mainly placed on the classical candidates. In this study, an overview of magnetless brushless machines including both the classical and advanced types is presented, with emphasis on their machine topologies, features and performances. In addition, the upcoming trend of these machines is reviewed and discussed. [ABSTRACT FROM AUTHOR]

This study presents a finite-control-set model predictive current control (FCS-MPCC) with phase shift compensation for a cost-effective voltage source inverter. Firstly, the FCS-MPCC algorithm uses the discrete-time model of the inverter to predict the coming value of the load current. In addition, a cost function is defined to evaluate all possible voltage vectors from the inverter, where the cost function is selected. Moreover, a pulse computation module is developed to obtain the final switching signals for insulated-gate bipolar transistors. In addition, the problem of current distortion caused by phase shift is solved by employing a time interval compensation factor. Furthermore, a comparison between the hysteresis control, pulse-width modulation control, and proposed predictive control is presented in terms of the steady-state and dynamic performances. Both simulation and experiment are conducted, which confirm the validity of the proposed control scheme of FCS-MPCC. [ABSTRACT FROM AUTHOR]

This study proposes a new dual-mode flux-switching doubly salient DC-field (FS-DSDC) machine for the wind power harvesting applications. The key distinction of the proposed machine is to artfully incorporate the design concepts of two machines, namely, the flux-switching DC-field (FSDC) and the DSDC machines together. By regulating the winding configurations, the proposed machine can behave similarly as the corresponding machines do and hence achieving the dual-mode operations, namely, the FSDC mode and DSDC mode, to offer higher flexibility and stability for different wind situations. The proposed machine can utilise its external DC-field winding to tune its flux density effectively, hence providing the constant-voltage charging function at various wind speeds and loads. The corresponding performances of the proposed machine are analysed by using the finite element method and verified by experimental results. [ABSTRACT FROM AUTHOR]

1. One of the most popular single-factor hypotheses that have been proposed to explain the naturalization and spread of introduced species is the enemy release hypothesis (ERH). Most studies have considered how specialist consumers might affect the success of exotics, but the importance of generalist herbivores has received little attention 2. In this study, we compared the palatability of native and exotic freshwater plants in both phylogenetic pairings and in region-wide assays, using a generalist consumer (the pond snail Radix swinhoei). 3. Our study indicated that, when plants were paired by taxonomic relatedness, the snail preferred native over exotic freshwater plants by a 2 : 1 ratio. The snail also preferred native over exotic plants when tested across 20 native and seven exotic species found growing in Liangzi Lake. 4. Snails consumed more biomass of native than exotic plants, providing support for the ERH and suggesting that exotic species have a potential advantage in most lakes of the middle and lower reaches of the Yangtze River in China, thus helping their invasion. [ABSTRACT FROM AUTHOR]