Andrzej Kapłon

Spectral inductance of the linear motor‐space harmonic analysis

Purpose – The aim of the paper is to present the methodology of obtaining an approximate equivalent circuit composed of lumped parameters which describes an electromagnetic state of induction machines (IMs) with solid secondary. Higher space harmonic field components are taken into account. The proposed method of machine model constructing is useful for solving electrodynamics states of solid secondary IMs, as well linear machines.Design/methodology/approach – A determination of equivalent circuit parameters of a polyharmonic machine is divided into two steps. In the first step, frequency plots of the spectral inductances are derived – for each of the space harmonic components – from an electromagnetic field distribution calculated by means of the finite element method. In the second step, each of the spectral inductances are represented by the operational inductances which corresponds to the equivalent circuit composed of parallel connected the magnetizing inductance and branches consisting of resistance...

Analysis of multipulse rectifiers with modulation in DC circuit in vector space approach

Rectifiers consisting of parallel connected 6-pulse bridges with modulation in DC current circuit show properties of 24-, 36-pulse or multipulse rectifiers. The analysis of such rectifiers was conducted by means of the space vector method. A load unbalance of the component bridges of 12-pulse rectifier generates the intermediate position of space vector on a complex plane. An increase in the number of the intermediate positions approximates the space vector to the case of rotating one. In this paper topologies of multipulse rectifiers with modulation in DC current circuit are presented. The simulation results of investigations were obtained by means of the space vector for control of modulators.

Estimation of electromagnetic parameters of an induction motor multi-loop equivalent circuit based on the machine inductance frequency characteristic

The variability of electromagnetic parameters of induction motors with deep-bar cage or solid rotors is represented, with a satisfactory approximation, by the machine secondary multi-loop equivalent circuit with constant lumped parameters. An estimation procedure of electromagnetic parameters of such an equivalent circuit is presented in the paper. The procedure is carried out using the measured frequency characteristic determined on the basis of instantaneous values of investigated induction motor electromechanical quantities. The study has been subjected to an induction motor with a solid rotor manufactured from the magnetic material, i.e. a machine characterized by a significant skin effect occurring in rotor solid conductive elements.

Experimental verification of DC/DC Boost converter calculation model considering conduction losses

This paper presents experimental verification of mathematical model of Boost DC/DC pulse converter structure with regard to conduction power losses for Continuous Current Mode (CCM). Measured characteristics of efficiency of energy conversion, voltage gain have been presented and compared with theoretical ones. Characteristics obtained on the basis of the model proposed in [1] well approximate experimental ones. Thus, the proposed model is suitable for converter projecting with the possibility to achieve predetermined efficiency of energy conversion and voltage gain at the stage of selection of converter elements.

Soft magnetic materials for energy-efficient electric motors

The paper presents different types of soft magnetic materials, which may be used for manufacturing of magnetic cores of energy-efficient electric motors. The properties of these materials are compared and their prospective influence on the efficiency of electric motors is discussed.

Induction motor electromechanical quantities estimation based on the inductance frequency characteristic — Simulation studies

The estimation methodology of electromechanical quantities of an induction motor has been presented in the paper. The investigated estimation algorithms are based on the motor inductance frequency characteristic and the machine secondary multi-loop equivalent circuit, reproducing this characteristic in the analyzed frequency range. The conducted simulation studies indicate the possibility of using the proposed algorithms in an estimation process of considered electromechanical quantities of an induction motor.

Magnetic Composites in Electric Motors

Magnetic composites are manufactured as magnetic powder bonded by dielectric material, which bond and insulate powder grains. Magnetic composites are applied in electric machines due to their favorable magnetic and mechanical properties as well as possibility of tailoring their physical properties. The paper is a review of soft and hard magnetic composites, their internal structure, properties, and advantages resulted from their application on magnetic circuits of electric motors.

Angular velocity estimator based on the inductance frequency characteristic for an inverter fed induction motor — Simulation studies

The selected simulation results of the angular velocity estimator, whose operation algorithm has been elaborated basing on the inductance frequency characteristic of the considered induction motor (IM), have been presented in the paper. The simulations have been conducted at specified operating frequencies of the scalar-controlled induction motor drive with a modulator employing the space vector pulse width modulation technique. This allowed for the indication of the influence of the IM current distortion on the accuracy of the IM angular velocity estimation process and thereby the efficiency of the considered IM drive. The impact of the estimator input signals filtering on the level of angular velocity estimation and tracking errors has been also investigated in the paper. The analysis has been conducted for the mathematical model of the four-pole induction motor of Sg 132S-4 type with a solid rotor manufactured from the magnetic material S235JR.

Results of load's observation for selected marine electric power plants systems in floating objects

Some aspects of marine electric power plants load registration and identification have been presented. Methods of operating data collecting about marine electric power plant loads have been shown based on an example of three vessels - a chemical tanker, a container ship and a tanker. Power plants of these vessels have been described. Examples of collected operating data were presented. Range of marine electric power plant load identification research has been characterized, which presented in the paper results are a part of.