Lorand Szabo

Induction Machine Bearing Fault Detection by Means of Statistical Processing of the Stray Flux Measurement

Rolling bearing faults are generally slowly progressive; therefore, the development of an effective diagnostic technique could be worth detecting such faults in their incipient phase and preventing complete failure of the motor. The methods proposed in the literature for this purpose are mainly based on measuring and analyzing vibration and current. Here, a novel technique based on the stray flux measurement in different positions around the electrical machine is proposed. The main advantages of this method are due to the simplicity and the flexibility of the custom flux probe with its amplification and filtering stage. The flux probe can be easily positioned on the machines and adapted to a wide range of power levels. This paper also reports an extensive survey on the stray-flux-based fault detection methods for induction motors, prior to introducing a novel sensor/diagnostic scheme.

Segmental Stator Switched Reluctance Machine for Safety-Critical Applications

In safety-critical systems, faults can cause life losses, environmental degradation, or significant financial losses. In this paper, a segmental stator switched reluctance machine is proposed for such applications. A short overview of its design is given. Its fault tolerance is investigated by dynamic simulations and laboratory tests. It is demonstrated via both methods that the proposed machine is able to have a continuous operation despite five severe winding fault conditions.

Study on fault tolerant switched reluctance machines

The papers goal is to compare a usual switched reluctance machine and a fault tolerant variant of it. By coupled Flux 2D and Simulink transient simulations the behaviour of the fault tolerant drive system under different winding fault conditions were studied. It was proved that using the proposed machine structure and converter topology same torque capability of the machine in faulty states as in healthy conditions can be assured. A short discussion on fault-tolerant converters is included in the paper, too.

Novel Permanent Magnet Tubular Linear Generator for Wave Energy Converters

Clean and sustainable alternative energy is becoming attractive as oil costs rise and the negative side effects of traditional energy systems begin to become apparent. One often overlooked, but still rapidly growing alternative is wave power. There are fascinating new designs for harnessing the tremendous power of the waves. Hence any contribution in this field could be of real interest for numerous specialists. In the paper a novel modular permanent magnet tubular linear generator is proposed and analyzed by means of numeric field computations. It was designed for wave power take off systems to be placed in the Black Sea near the Romanian coasts.

Study on a simplified converter topology for fault tolerant motor drives

Some of the recent research activities in the area of electrical machines and drives for critical applications (such as aerospace, defence, medical, nuclear power plants, etc.) are focused on looking for various special motor and converter topologies. Nowadays by the help of recent technological advances and developments in the area of power electronics and motor control the fault tolerant electrical machine and drive concept is at a level where it begun to be feasible to be used in practice [1]. Therefore any new results could be of real interest for all the specialists working in these fields. In the paper a simplified power converter topology is proposed for a nine-phase fault-tolerant permanent magnet synchronous machine. By coupled Flux 2D and Simulink transient simulations the behaviour of the drive system under different winding fault conditions is studied. It is proved that using the simplified converter topology near the same torque development capability of the machine in faulty states can be assured. Short discussion on making the converter also fault-tolerant is included in the paper, too.

Electrical Machines Virtual Laboratory: Grid Connection of a Synchronous Generator

Virtual laboratories can become important components of the teaching process, because using them several experiment-oriented problems can be solved easily and also from the distance. Graduates using virtual laboratories will be better trained when they enter the job market. In the paper a laboratory work will be presented having two components: a simulation and an experimental module. Both can be used for the preparation of a real lab and for accessing the real-world experiments. The virtual lab modules can also allow multiple students to remote access the experiments, the multicast data transfer mechanisms and arbitration mechanisms

Motorization for an Electric Scooter by Using Permanent-Magnet Machines Optimized Based on a Hybrid Metaheuristic Algorithm

This paper deals with the proposition of a permanent-magnet (PM) machine used to motorize an electric scooter. Several electrical machine configurations are discussed, and the best solution is chosen. The power density and the energetic performances of the chosen machine (with a fractional-slot configuration) are improved using a hybrid optimization algorithm, which combines simulated annealing (SA) and particle swarm optimization (PSO) techniques. The obtained results are numerically and experimentally validated to prove that the proposed solution suites the scooter application.

Comparison of the main types of fault-tolerant electrical drives used in vehicle applications

A comparative study of several fault-tolerant electrical drives is presented in this paper. As the application is concerned, the authorspsila attention was oriented towards the vehicle transportation. Thus, the main electrical drives under study are: the induction, the switched reluctance and the permanent magnet synchronous machine, respectively. The present work will explore the aforementioned drivespsila capabilities in terms of fault-tolerant operation. The authors present a substantial study for the fault-tolerant issue in electrical drives by using finite element method (FEM). During this numerical analysis many phenomenon will be emphasized and, coming together with some tests, final conclusions will be depicted.

Speed-thrust control of a double sided linear switched reluctance motor (DSL-SRM)

The speed and thrust control strategy for a double sided linear switched reluctance motor (DSL-SRM) is elaborated in the paper, based on a simplified analytical model. The strategy is defined for different motor phase supply conditions and the dynamic characteristics are calculated via computer simulation for a sample motor, in order to sustain the theoretical results.

Wave Energy Plants for the Black Sea Possible Energy Converter Structures

It is crucial for the mankind to develop clean renewable energy sources. Ocean energy is one of the candidates being a huge, yet unexploited renewable energy source on the Earth. Preliminary surveys show that marine power has a potential to supply a significant part of the future energy needs. Hence all the researches done in the field of the wave energy conversion should be of real interest. In this paper the wave energy potential of the Black Sea near the Romanian coasts, a possible power take off system to be set up here, respectively a comparative study on two possible linear generators to be used in such wave energy power converters will be presented.