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A study of the effect of poling conditions on screen‐printed piezoceramics was undertaken. Printable pastes were produced, using a commercially available lead zirconate titanate (PZT) powder, mixed with two types of binder, lead (II) oxide and a lead borosilicate glass. Sample devices were fabricated using the two paste types and processed, using standard thick film techniques, before being poled under varying conditions. Samples were compared by measurement of piezoelectric charge constant, d₃₃ and using scanning electron microscopy techniques. Temperature and time are shown to increase poling efficiency, while poling field reaches an optimum at 2‐3 MV m^‐1. The PZT layers start to fail through a process of dielectric breakdown at fields of 3.5 MV m^‐1 and above.

Introduces the fourth and final chapter of the ISEF 1999 Proceedings by stating electric and magnetic fields are influenced, in a reciprocal way, by thermal and mechanical fields. Looks at the coupling of fields in a device or a system as a prescribed effect. Points out that there are 12 contributions included ‐ covering magnetic levitation or induction heating, superconducting devices and possible effects to the human body due to electric impressed fields.

The purpose of this paper is to describe designing Pobot V2, a robot capable to climb poles with a cylindrical or conical shape.

This paper describes the design of the pole‐climbing robot Pobot V2, based on the innovative principle of rolling self‐locking that uses no energy to maintain itself at a given altitude.

The robot is also capable of avoiding tangential obstacles, crossing small collars and regulating passively its normal contact force on conical poles with a diameter that evolves from 300 to 100 mm. The work is validated by experiments. The robot can also perform axial rotation, can cross‐tangential obstacles and climb poles with a strong conical shape, due to passive normal force regulation with springs and a force amplifying linkage. The first experiments showed excellent stability during vertical climbing.

More work will be required to make the robot more rigid, more compact, and lighter. The robot is jointly patented by Thales and IFMA.

It is original because of its rolling self‐locking concept: rolling allows continuous ascension whereas self‐locking guarantees a null energy consumption while staying still on the pole.

Axial field flux-switching permanent magnet machine (AFFSPMM) can be applied in the field of electric and hybrid electric vehicles because of short axial size, large torque density, and high-power density. The purpose of this paper is to improve the reliability of AFFSPMM itself, the design parameters have to be considered for attaining high self-inductances and reduced mutual-inductances.

The original parameters of E-core AFFSPMM are designed with reference to a 600 W prototype, on the basis of which the 3-D model of the original AFFSPMM is established, and the inductances are calculated by finite element method. The influence of these parameters on the inductances, including combinations of stator and rotor pole numbers, spilt ratio, stator side tooth width, magnet thickness, and rotor pole width etc., are respectively investigated and analyzed under the constant copper loss.

The relationships of rotor pole numbers and inductances are deduced on the condition of the fixed stator poles. It is found that the rotor pole numbers has significant effects on the ratio of mutual-inductance to self-inductance, and the self-inductance is mainly affected by the rotor pole numbers, the split ratio, the stator tooth width, and the rotor pole width. The asymmetry of back-EMF can be largely reduced by optimizing the rotor tooth width. In this paper, the static characteristics are compared and analyzed for the original and optimal 6/14-pole AFFSPMM. Meanwhile, the open-circuit and short-circuit fault are investigated by transient analysis. The results show that the optimized E-core AFFSPMM has good fault tolerance.

The research of inductance characteristics for E-core AFFSPMM is valuable to design the fault-tolerant machine, by which the cost of control and manufacture can be largely saved.

A study has been carried out on the relationship between the composition, poling condition and piezoelectric properties of thick film layers. Pastes based on lead‐titanate‐zirconate (PZT) powders, with either PbO or a lead‐alumina‐silicate glass frit as binder, were prepared. Microstructure, electrical and mechanical properties were analysed. Processing and poling conditions modify these properties; then a wide latitude of opportunities is offered in the choice of ferroelectric/piezoelectric characteristics of the layers used as sensing elements for sensors. A pressure sensor was realised where a circular diaphragm of alumina supports two piezoelectric layers obtained by screen printing and firing a PZT/PbO‐based ferroelectric paste. The design and the performance characteristics are described.

The purpose of this paper is to present a new computational fluid dynamics model for large electrical machines to simulate the heat transfer at specific components to the appropriate ventilation method. The most damageable parts for overheating in generators are the end winding bars, pole windings and stator ducts.

The reduced model introduced is basically derived from the state-of-the-art pole section model (PSM) and enables faster computations for heat transfer and cooling simulations of electrical machines. The fundamentals of the two methods and the grid generation are described. Two PSMs and four different reduced models are presented and compared among each other to tune the reduced model.

As a topic of outstanding interest in large hydro generators, the heat transfer at the end winding bars is solved with the aid of the reduced model. This slot sector model (SSM) has been validated and the computation time has been reduced enormously in comparison to the state-of-the-art PSM.

The heat transfer has been carried out only for the end winding region of large hydro generators. The effect of the reduced model on the pole sections and stator ducts has not been investigated. Nevertheless, the reduced model is also valid for large motors.

This reduced model can finally be used for parametric studies with different cooling schemes and boundary conditions in the design process.

The comparison of various SSMs to PSMs shows an acceptable accuracy of the reduced model in combination with a rather low computation time. Due to modeling one slot only, the MFR-MP approach is an adequate and fast analyzing method for this kind of model structure.

This article is concerned with the application of human statistical techniques to risk engineering in the electricity distribution system in Australia. It examines legal negligence in terms of the cause of action, care and duty, and economic criteria. A mathematical hazard model of risk analysis is presented.

The high computational effort of steady-state simulations limits the optimization of electrical machines. Stationary solvers calculate a fast but less accurate approximation without eddy-currents and hysteresis losses. The harmonic balance approach is known for efficient and accurate simulations of magnetic devices in the frequency domain. But it lacks an efficient method for the motion of the geometry.

The high computational effort of steady-state simulations limits the optimization of electrical machines. Stationary solvers calculate a fast but less accurate approximation without eddy-currents and hysteresis losses. The harmonic balance approach is known for efficient and accurate simulations of magnetic devices in the frequency domain. But it lacks an efficient method for the motion of the geometry.

The three-phase symmetry reduces the simulated geometry to the sixth part of one pole. The motion transforms to a frequency offset in the angular Fourier series decomposition. The calculation overhead of the Fourier integrals is negligible. The air impedance approximation increases the accuracy and yields a convergence speed of three iterations per decade.

Only linear materials and two-dimensional geometries are shown for clearness. Researchers are encouraged to adopt recent harmonic balance findings and to evaluate the performance and accuracy of both formulations for larger applications.

This method offers fast-frequency domain simulations in the optimization process of rotating machines and so an efficient way to treat time-dependent effects such as eddy-currents or voltage-driven coils.

This paper proposes a new, efficient and accurate method to simulate a rotating machine in the frequency domain.

Present methods of establishing inspection and maintenance programs for wood poles are prescriptive in nature and do not consider the life data of poles in a particular region. In this paper, a methodology is discussed for estimating the useful life of older poles having survived a certain number of years, using life data analysis. A procedure is presented to establish the timing of the next inspection of older poles based on the current acceptable replacement rate.

Reports on a study of consumer banking habits in Poland compared with findings in other countries to determine whether bankers need to adopt different strategies in the relatively new free‐market economies. First, presents an overview of the evolution of the Polish banking system since the restructuring of the National Bank of Poland in 1987 and the resulting intensively competitive environment for new banks. Second, reports on the reasons why Poles have chosen specific banks. Finds that in Poland, as in other countries, the most important variables influencing customer choice are reputation, price and service, but with certain variations related to the Polish context. Concludes with a discussion of the implications for marketing strategy formulation and implementation.