This study proposes a novel and compact AC/DC electrical distribution system for new generation aircraft. In these new aircraft power systems, all loads are fed by two DC bus systems: at 28 V and at ±270 V. The electrical distribution system, whose design and implementation are described in this study, has only one primary AC source (360–900 Hz at 230 V) with all the required DC voltage levels being derived from this source. This solution enables elimination of the complex mechanical coupling apparatus currently used, for fixed frequency AC systems, to maintain the generator speed at constant level while the engines operate at variable speed. Under the proposed solution, all the conversion stages needed to generate various output voltage levels are implemented by using power converters assembled in one unit. Each converter has a current control loop in order to regulate the output current even during output line short circuits and also to limit the inrush current to the circuit at turn-on. To prove the concept, a 5 kW prototype was designed and tested, and demonstrated to meet all the specifications within the relevant standards regarding input and output power quality.

A rail eddy current brake (ECB) controller is proposed to produce the optimum braking and attractive forces using the variation of the reference current according to the speed. To improve the operation of the ECB, an optimal design of the controller is carried out by means of finite element method. Kriging method is utilised to reduce the computational costs. Additionally, the genetic algorithm is used as a multiobjective optimisation method to find the optimum current references in different speeds.

Predictive Maintenance, Prognostics and Reliability Centered Maintenance approach are becoming more and more important in the railway sector to reduce costs of operation and to increase reliability and safety. In fact, these are fundamental to optimize the maintenance process, to define new measures and algorithms which locate faults, to monitor health conditions of subsystems and to estimate residual life of components.

In some cases it's possible to use existing sensors and existing processing hardware to extract new information from the existing available data. It's clear that this is usually the best option because the benefit can be achieved with little or no cost at all. This paper describes the result of a study performed with the aim of detecting arcing events without the need of additional equipment mounted on board the train. A set of data relative to voltage and current collected on high speed trains along with a set of measurements coming from photosensors are available. The data are processed by the use of an advanced classification technique, Support Vector Machines, with the aim of extracting important information such as the time coordinate related to anomalies in the overhead contact line and the status of the pantograph contact strip.