Relays, Working principle of relay,

            Introduction:

An electrical relay is a switch which is under the control of another circuit. A classic example of an electrical relay is the system used to start a car. When someone turns an ignition key, the ignition does not interact directly with the car battery.

Grid Substation, Introduction, Grid station and National Grid substations

Grid Substation                                                            

  Introduction:

A grid substation is part of the electricity grid system -i.e. part of the transmission system. In the Bangladesh, this involves voltage levels of 400 kV, 230 kV, 132KV,66,11KV,  KV,440V,220V132 kV.Transmission of power occurs through the power distribution grid.

Recommendation for Future Work ,Results Validated By Theoretical Modeling and Development of Algorithm

Recommendation for Future Work:

          In the whole research work, attention was paid to simulate all the structures by commercial EM software Zeland IE3D. Investigations need to be justified experimentally by VNA and compared with simulated results.

Performance of uniform circular PBGS Assisted BPF, Performance of reference BPF, Performance of BPF on 2-D array of uniform circular PBGSs, Performance of BPF on dense 2-D array of uniform circular PBGSs, Performance of BPF with three line uniform circular PBGSs, Performance of BPF with uniform circular PBGSs under two extreme 50 ohm lines, Performance of BPF with uniform circular PBGSs under all the lines Performance of BPF with uniform circular PBGSs under all the line

    Performance of uniform circular PBGS Assisted BPF

Theoretical results are produced for different geometries of uniform circular PBGS assisted BPF. To see the effect of uniform circular PBGS in harmonic suppression the performance of reference BPF is shown. Finally the insertion loss performances of a standard BPF and uniform circular PBGS assisted BPF are shown to compare the results.

Simple T-line and its performance, S-Parameter Performance of a microstrip T-line, Design of uniform circular PBGSs for Harmonic Suppression, Standard BPF, BPF on 2-D array of uniform circular PBGSs, BPF with dense 2-D uniform circular PBGSs, BPF with PBGSs under 50-ohm and central coupled lines

    Simple T-line and its performance:

T-line is just a line with a defined length and width on the upper surface of the substrate which is created by removing copper coating from the surface except the desired region. The figure is shown below where the blue region is a typical T-line whose length is 100 mm and width is 2.2642 mm (calculated by PCAAD for 50Ω microstrip T-line where dielectric constant of the substrate is 2.45 and thickness is 31 mils).

Microwave Filter design, Applications to BPF ,Application to LPF, Application to dual stopband filter, Band-pass filters

Microwave Filter design

              There is a vast amount of published literature on the design of microwave filters from which some are highly mathematical. Fortunately there are some relatively straight forward procedures which enable us to design certain useful classes of microwave filters. Filter designing using the image parameter method consist of a cascade of simpler two-port filter sections to provide the desired cutoff frequencies and attenuation characteristics but do not allow the specification of a frequency response over the complete operating range.

Microwave Filters,Lumped - element LC filters , Planar filters, Coaxial filters, Cavity filters, Dielectric filters and Electro acoustic filters

Lumped - element LC filters

An LC tank circuit consisting of parallel or series inductors and capacitors is a best example of a simplest resonator structure. These LC tank circuits have the advantage of being very compact & small in size, but having the low quality factor of the resonators which leads to relatively poor performance. 

Figure: Commercial photograph of Lumped-element LC filters.

Introduction, Microwave filters, Filter and There are mainly four types of filters with respect to functions

  Microwave filters

   Introduction

          A filter is a two-port network used to control the frequency response at a certain pointin an RF or microwave system by providing transmission at frequencies within the passbandof the filter and attenuation in the stopband of the filter.

Microwave filters represent a class of electronic filter design to operate on signals in the MHz to GHz frequency ranges. This frequency range is the range used by most broadcast radio, television, wireless communications like Cell phone, Wi-Fi, Wi-Max and the most radio frequency and microwave devices will include some kinds of filtering on the signals transmitted or received.

Gas Turbine Power Plant Modelling for Operation Training

           The $11.4 billion worth of non-aviation gas turbines produced in 2008, $9.6 billion—more than 80 percent—were for electrical generation (Langston, 2008). Particularly, in Mexico, about 15% of the installed electrical energy (no counting the electricity generated for internal consuming by big enterprises) is based on gas turbine plants (CFE web page), either working alone or in combined cycle power plants (and 8% produced directly by gas turbines) that offers an important roll in improving power plant efficiency with its corresponding gains in environmental performance (Rice, 2004).

The Biased p-n Junction

     An externally applied potential will alter the potential difference between the p- and n-regions. This in turn will modify the flow of majority carriers, so that the junction can be used as a “gate”. If the junction is forward biased by applying a positive voltage V to the p-region Fig. , its potential is increased with respect to the n-region, so that an electric field is produced in a direction opposite to that of the built-in field.

THE IGFET/MOSFET

The second (and most important) family of FETs are those known under the general title of IGFET or MOSFET. In these FETs, the gate terminal is insulated from the semiconductor body by a very thin layer of silicon dioxide, hence the title ‘Insulated Gate Field Effect Transistor,’ or IGFET. Also, the devices generally use a ‘Metal-Oxide Silicon’ semiconductor material in their construction, hence the alternative title of MOSFET.

Distribution network configurations

Distribution networks are typically of two types, radial and interconnected (see spot network). A radial network leaves the station and passes through the network area with no normal connection to any other supply. This is typical of long rural lines with isolated load areas.