P2-0114 — Annual report 2009
1.
Nonstationary Vibration and Transition through Fundamental Resonance of Electromechanical systems Forced by a Nonideal Energy Sources

Presented in the paper is The Extended Lindstedt-Poincare (EL-P) method, with multiple time scales for the treatment of the nonstationary vibrations of the electromechanical converters and system. Vibrations are forced by a nonideal energy source. The presented method can be easily applied for analysis of mechanical vibrations in different types of electro motors or electric drives. It can be extended with the inclusion of the superharmonics and subharmonics, as well as it can be used for the stability analysis.

COBISS.SI-ID: 13234454
2.
Electric field distribution under transmission lines dependent on ground surface

The paper presents the electric field analysis in the high voltage power line surroundings. A treated power line is a typical low frequency radiation source. The influence of the conductive bodies and of the ground configuration in the surroundings of the 400 kV power line on the electric field distribution was analyzed. To consider the mentioned influences is very important for the real picture about the electric field distribution in the power line surroundings. The paper proves that fact. The usual analyses are made for the ideal flat ground surface, which is not real in majority of cases.

COBISS.SI-ID: 13438998
3.
Application of the hybrid multiobjective optimization methods on the capacitive voltage divider

The paper describes the development and application of the multi-objective hybrid optimization algorithm on the numerical model of the voltage divider, which is based on the finite element method. The goal of the research is to achieve reliable, robust and fast convergence of the optimization process, whereas the non-dominant solutions on the Pareto front need to be diverse. The optimization is carried out with the Differential Evolution algorithm, which is improved in the selection step. The algorithms MODE-II and NSDE are also introduced to the procedure.

COBISS.SI-ID: 13078294
4.
Torque analysis of an axial flux permanent magnet synchronous machine by using analytical magnetic field calculation

The paper presents a torque analysis of an axial flux permanent magnet synchronous machine, based on analytical analysis of magnetic field. The proposed method for torque analysis requires less computational time and it is more flexible than finite element method. This is an important advantage, especially for early stage of the design process. Torque measurements of the prototype confirm the validity of torque analysis method.

COBISS.SI-ID: 13078550
5.
Comparison of electromechanical characteristics of three phase induction motors with different pole and slot number combinations

The comparison of electromechanical characteristics of a 4-pole and 6-pole induction motor, with 36 stator slots in combination with 28, 33, 34, 44 and 46 rotor slots is presented. The paper evidently shows the motors that exhibited low values of iron losses at no-load also exhibited superior line-starting performance, high values of torque per unit stator current and superior efficiency at rated load. Moreover, the paper shows the feasibility of using the same stator and rotor slot combinations for a mid-size 4-pole and 6-pole induction motor.

COBISS.SI-ID: 13670166