The unique properties of high critical temperature superconductors (HTS) make possible the development of an effective and self-stable magnetic levitation (MagLev) transportation system. In this context, a full scale MagLev vehicle, named MagLev-Cobra, has been developed at the Laboratory for Applied Superconductivity (LASUP/UFRJ). The vehicle is borne by a linear superconducting magnetic bearing (LSMB). The most important design constraint of the levitation system is the force that appears due to the interaction between the HTS and the permanent magnetic (PM) rail, which composes the LSMB. Static and dynamic characteristics of this force must be studied. The static behavior was already reported in previous work. The dynamic operation of this kind of vehicle, which considers the entry and exit of passengers and vibration movements, may result in the decrease of the gap between the superconductor and the PM rail in LSMB. In order to emulate the vehicle operation and to study the gap variation with time, the superconductors are submitted to a series of vertical displacements performed with the help of an experimental test rig. These movements are controlled by a time-variant reference force that reproduces the vehicle dynamic. In the present work, the results obtained for the dynamic gap behavior are presented. These measurements are essential to the commissioning process of a superconducting MagLev full scale vehicle.

The complex microstructure of melt grown YBCO bulk material and the non-linear electromagnetic behavior makes it difficult to determine their thermal, electrical and magnetic properties. The knowledge of these parameters is essential to design superconducting magnetic bearings (SMB) for various applications. The main characteristic of a SMB is the levitation force that arises between the superconductor and the magnetic source. The availability of simulation tools can greatly simplify the design of new prototypes. An algorithm based on the critical state model and the Finite Element Method (FEM) was developed. This method is based on the determination of the current density profile within the superconductor due to the penetration of the flux lines. This algorithm showed satisfactory to simulate the levitation force for a rotational magnetic bearing used in a flywheel prototype. In the present paper, this method is used to simulate a linear bearing and to design the optimal geometries for a magnetic rail that is being developed for a MAGLEV vehicle prototype. The linear bearing consists of two parts: a rail assembled with Nd-Fe-B magnets and YBCO bulks mounted inside a cryostat. Some simulated bearings were mounted and tested. The simulation results agree with the measurements.

O trabalho apresenta a proposta de sistema de microgeração de energia elétrica conectado à rede, integrado à cobertura de uma edificação do Campus Praia Vermelha na UFF, e sua avaliação econômica no âmbito dos possíveis cenários de compensação propostos pela ANEEL para a revisão da Resolução Normativa nº 482/2012. São apresentadas as características gerais da edificação e do sistema fotovoltaico proposto, além das estimativas de consumo de energia elétrica e da geração fotovoltaica. Analisou-se o tempo de retorno do investimento e o custo nivelado da energia fotovoltaica como base de comparação de cada cenário analisado.