During the switching on/off of shunt capacitor banks in substations, vacuum circuit breakers (VCBs) are required to switch off or to switch on the capacitive current. Therefore, the VCBs have to be operated under a harsh condition to ensure the reliability of the equipment. This study presents a complete comparison study of ordinary and phase-controlled VCBs on switching 10 kV shunt capacitor b...

A logarithmic term is applied to account for the charge transfer overvoltage with most empirical polarization curve fitting equations for polymer electrolyte membrane fuel cells. The logarithmic term applied with state-of-the-art fitting equations is proportional to the logarithm of the cell output current density. This provides good fitting characteristics with large current densities, but res...

Original scientific paper The increasing sensitivity of electronic devices widely used in low-voltage AC systems requires an appropriate protection against voltage and current surges. Protection of the equipment against the prospective surges is based on application of surge protection devices (SPDs). Most common situation, especially in residential buildings, is application of only one SPD at ...

Electron channeling effects can create measurable signal intensity variations in all product signals that result from the scattering of the electron beam within a crystalline specimen. Of particular interest to the X-ray microanalyst are any variations that occur within the characteristic X-ray signal that are not directly related to a specimen composition variation. Many studies have documente...

To improve the overall dynamic performance of induction motor in direct torque control (DTC), a novel method of stator resistance estimation based on multi-resolution analysis wavelet PI controller is presented. This estimation method is anchored in an on-line stator resistance correction regarding the variation of the stator current estimation error. The main purpose is to adjust precisely the...

In this paper, the mathematical modeling and simulation of electromagnetic transient processes is considered, which is of vital importance for examining the overvoltage phenomenon of power transmission systems. In the mathematical models of the AC power transmission systems that contain a power source, the power transformer, transmission line, and power autotransformer block are presented. The ...

In renewable power generation doubly fed induction generators (DFIG) are used, in which the stator of the generator is directly connected to mains, while the converter for the rotor is rated only for slip power. Due to the interaction of rotor and stator windings in a DFIG, the high-frequency harmonics caused by the pulsed output of rotor power converters are transmitted into the stator current...

This paper presents an online stator resistance estimator to achieve precise torque control of CSI fed PMSMs over a low speed operating region. A quick and precise control several researchers have proposed implementations combining the use of permanent magnet synchronous motor with the direct torque control (DTC) technique. The electromagnetic torque, stator flux and rotor position can be estim...

− Accurate knowledge of stator resistance is of utmost importance for correct operation of a number of speed sensorless induction motor control schemes in the low speed region. Since stator resistance inevitably varies with operating conditions, stable and accurate operation at near-zero speed requires an appropriate on-line identification algorithm for the stator resistance. The paper proposes...

The model for the stator-rotor interaction is discussed in the sections The stator-rotor interaction and The rotor switching dynamics of the main text. The model is based on the model Oster and Blair and coworkers [1, 2] and Meacci and Tu [3], but extended to include the conformational transitions of the rotor protein complex. Here, we discuss aspects of the model that are not discussed in the ...