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Winding losses in Brushless Permanent Magnet (BPM) machines are typically, one of the largest loss contributions, especially in high speed applications such as e-chargers, compressors and traction. For this purpose, it is crucial to predict and take into account also the AC winding loss component, in order to reduce the total amount of stator winding losses. In this paper, a comparative study of aluminum and copper windings is conducted with the aim of mitigating the effect of the winding losses. The study is carried out considering two high speed machines. The first one is the main motor of an electric powertrain, developed for a fully electric motorsport application, whereas the second one is a high-speed turbocharger for an electric vehicle power boost application.

New inverter technology can make enormous improvements in EV efficiency and it’s all thanks to one amazing substance, says Ian Foley, managing director, Equipmake

As Life in Towns and Cities Might Return to a Form of Normality this Year, Ian Foley, Managing Director at Equipmake, Explains why we have to Address Urban Emissions and Suggests an Alternative Route for the UK to take on Electrifying Public Transportation

The objective of this paper is to introduce a new high performance electric motor for a high speed and torque motor sport application. A compact radial flux machine, with double layer concentrated winding and interior permanent magnets has been designed to achieve high torque with a low weight. The motor is made with 18 copper coils, 6 per phase, pre-wound and placed in the slots, which are directly cooled by forced oil. The motor is also equipped with a shaft spiral groove cooling system for magnet temperature control.

Attraction of the invasive snail Xerolenta obvia (Menke, 1828) to chopped cucumber and to a previously identified attractant based on a steam distillate of dry cat food was assessed with an established field population in Montana. Snails were significantly more attracted to the chopped cucumber than bottled water (control), using both traps and direct observations of attractants deployed in Petri dishes. The chopped cucumber also attracted significantly more snails to traps than the cat food distillate. These results suggest that chopped cucumber could constitute a cheap and simple lure for this and other invasive mollusk species. In addition, odors of chopped cucumber may support development of a new artificial lure, through analysis and reconstruction of the odor with synthetic compounds.

This paper presents a newly developed high torque density motor design for electric racing cars. An interior permanent magnet motor with a flux-concentration configuration is proposed. The 18slots/16poles motor has pre-formed tooth wound coils, rare-earth magnets type material, whilst employing a highly efficient cooling system with forced oil convection through the slot and forced air convection in the airgap. Losses are minimized either by using special materials, i.e. non-oriented thin gage, laminated steel or special construction, i.e. magnet segmentation or twisted wires. The thermal behavior of the motor is modelled and tested using Le Mans racing typical driving cycle. Several prototypes have been built and tested to validate the proposed configuration.

Microbial biofilms are notably recalcitrant towards treatment with antibiotics, biocides or disinfectants that would adequately control the same organisms growing in planktonic mode. Much of this resistance has been attributed to an organisation of the biofilm cells within exopolymer matrices. Whilst such exopolymers are unlikely to hinder the diffusion and access of antimicrobial agents to the underlying cells, they will chemically quench reactive biocides such as chlorine and peroxygens, and bind highly charged antibiotics, such as tobramycin and gentamycin, thereby providing some protection to the more deep lying cells. Extracellular enzymes, bound within the glycocalyx and able to degrade the treatment agents, will further reduce the access of susceptible compounds. Diffusion limitation however, is unlikely to be the sole moderator of the resistance properties of microbial biofilms. In addition, gradients of oxygen and nutrients established across the biofilm community will cause growth rates to be much reduced at points remoted from the accessible nutrient. Slow growth rates, and the associated induction of stringent responses further contribute towards this resistance. Finally, there have been recent demonstrations that attachment of microorganisms to surfaces promotes the expression of genes that are not normally expressed in planktonic culture. Whether or not the expression of such genes alters the phenotype in a manner which alters the response of the cells to antimicrobial agents remains to be demonstrated.