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This paper illustrates the operation of a tubular-machine drive as a linear generator for a heave-buoy wave energy conversion. Linear generators, which are adopted in marine power plants, offer the advantage of generating without introducing any conversion crank gear or hydraulic system. The use of a tubular-machine topology allows the electromagnetic thrust density to be improved. This paper briefly summarizes the principles of marine wave buoy interaction and reports the design analysis and control of a permanent-magnet (PM) synchronous tubular linear machine based on a scaled generator prototype and on a rotating simulation test bench. Index Terms--Heave buoy, linear synchronous generators, marine energy, tubular generators.

The traction control is a tool to increase stability and safety and it has a greater performance potential in electrical vehicles (EVs) than in internal combustions vehicles. Moreover, the traction control allows the EV to operate more efficiently preventing slippage in acceleration and permitting the use of use high-efficiency low-drag tires. The presented approach can compete with the well-recognized techniques, but it offers a lighter tuning procedure. This paper presents an approach to the longitudinal control of a single wheel adopting a configuration based on an adherence estimator and a controller of the adherence gradient. Two adherence gradient controllers are examined in the paper: a fuzzy controller and a sliding mode controller. In both cases, the presented approach allows for tracking a value of the adherence derivative in a wide operating range without any knowledge of the road conditions. The work is based on numerical simulations as well as experimental tests. The test bench computes in real-time the vehicle dynamic and loads accordingly, the drive under test. Both controllers were experimentally verified showing good behavior and good response to a sudden change in the road characteristics, whereas the best overall performance was recorded with the sliding mode control. Index Terms--Electric vehicle (EV).

The adoption of High Temperature Superconductors (HTS) tapes is becoming a suitable and interesting alternative to copper for windings in transformers, thanks to the improvement in performance and the lowering of costs. Of course, optimized designs, different with respect to usual layouts, must be considered, due to the additional requirements of HTS tapes, such as minimization of orthogonal magnetic fields and consideration of additional losses in the HTS. In the framework of a scientific cooperation among some Italian Universities and private companies, a test model for a 10 KVA transformer with HTS secondary windings has been developed, and validated against a demonstrative prototype, manufactured during the project. In the paper, the device model performance is assessed, with particular care to the HTS losses modeling, and some comparisons to the experimental results are presented. [ABSTRACT FROM AUTHOR]