The paper deals with the metrological characterization of a digital wattmeter developed by using a personal computer, a shunt, two commercial data acquisition boards and commercial software. The uncertainty of the active power measurements is assessed individually characterizing the voltage channel, the current channel and the phase displacement measurement between the two channels. In particul...

This paper presents a technique for diagnosis of the type of fault and the faulty phase on overhead transmission line. The proposed method is based on the multiresolution S-transform and Parseval’s theorem. S-transform is used to produce instantaneous frequency vectors of the voltage signals of the three phases, and then the energies of these vectors, based on the Parseval’s theorem, are utiliz...

the produced liquid water in cathode catalyst layer (ccl) has significant effect on the operation of proton exchange membrane fuel cell (pemfc). to investigate this effect, the transport of oxygen in ccl in the presence of immiscible liquid water is studied applying a two-dimensional pore scale model. the ccl was reconstructed as an agglomerated system. to explore the wettability effects, diffe...

abstract: this paper discusses two topics. at first, it uses continuous wavelet (morlet) transform, coherency, and phase angle analysis to study the effect of mean volatility in opec crude oil prices, wti crude oil prices, brent crude oil prices and iran’s crude oil prices on the iran’s reer. to this end, the monthly data of the variables for years 2003 to 2012 is used. coherency analysis revea...

Abstract—In this paper, the equivalent circuit of the ideal singlephase power transformer with its appropriate voltage current measurement was presented. The calculated values of the voltages and currents of the different connections single phase normal transformer and the results of the simulation process are compared. As it can be seen, the calculated results are the same as the simulated res...

Specific heat spectroscopy was used to study the dynamic glass transition of ultrathin poly(2-vinyl pyridine) films (thicknesses: 405-10 nm). The amplitude and the phase angle of the differential voltage were obtained as a measure of the complex heat capacity. In a traditional data analysis, the dynamic glass transition temperature Tg is estimated from the phase angle. These data showed no thic...

A novel frequency-to-voltage converter based phase-locked loop (PLL) is proposed to overcome the inability of a frequency-locked lock phase. The dual-loop PLL adds variable phase-locking capability, such that phase locking angle can vary from 0–360°. additional be applied in data communication form modulation. design targeted for 0.5-?m CMOS process. generates 480 MHz clock reference 15 MHz. In...

Speed, position and load characteristics of the ultrasonic motor is considerably influenced from the input characteristics such as driving frequency, magnitude and phase difference of phase voltages. Input and output characteristics of a traveling-wave ultrasonic motor have been investigated from the experimental point of view in the present study. For this aim, a half-bridge serialresonance in...

This paper presents a single phase 7-level half bridge cascade dual buck multilevel grid-tied inverter with both active and reactive power flow control in a wide range under two types of renewable energy. The power flow is controlled by varying the switching pulse of the power semiconductor device used in the half bridge cascade dual buck multilevel grid-tie inverter. The multicarrier sinusoida...