The aim of this paper is to present the difference of induction machine electromechanical characteristics in motor and generator operating modes. Firstly, the paper presents analytically derived equations, which are based on equivalent circuit and are used for calculation of induction machine breakdown torque. Secondly, a comparison of calculated and measured characteristics in motor and genera...

Stray load loss refers generally to the sources of induction machine loss not accounted for by typical calculations of primary or secondary copper loss, no load core loss, or friction and windage loss. Harmonic rotor bar currents from the non-sinusoidal distribution of the slotted stator winding contribute significant stray load loss. Rotor bars, especially on cast rotors for machines under fif...

From the rating plate data of an induction motor the nominal efficiency can be determined. Without detailed knowledge of equivalent circuit parameters, partial load behavior cannot be computed. Therefore, a combined calculation and estimation scheme is presented, where the consistent parameters of an equivalent circuit are elaborated, exactly matching the nominal operating point. From these par...

The paper presents an improved equivalent circuit parameters extraction method for the dumbbell-shaped defected ground structure (DGS). The new extraction parameters equations are obtained in closed-form expressions, which contain S11 and S21. The DGS unit with center frequency of 5 GHz is designed and fabricated on a TLX substrate with thickness of 1 mm and dielectric constant of 2.55. The cir...

In this study, the signal paths in intrabody communication channels are discussed by evaluating the electric fluxes between conductors and the earth ground. This study is based on the equivalent circuit model of which parameters are obtained via an electrostatic analysis. The obtained results clarified the electric flux flows in the communication channels, and they quantitatively support the pr...

This work presents a method based on elementary concepts of electric network for characterization of piezoceramics. A simplified version of Mason’s equivalent circuit is obtained applying basic theorems of electricity. The methodology employed to simplify the circuit is mandatorily presented in the issues addressed in introductory courses of electric circuits. The experimental development can b...

In order to reduce the dipole wake encountered by the first few bunches accelerated in a multi-bunch NLC scenario the DDS (damped detuned structure) was re-designed such that a much improved Gaussian fall-off occurs in the initial wake-function. From the 9 parameterised model of DDS1 we use a mapping function to allow DDS 3 & 4 to be modeled and hence avoid additional and prohibitively time con...