Electrical Engineer

Electrical Bus-Bar and its Types Definition : An electrical bus bar is defined as a conductor or a group of conductor used for collecting electric power from the incoming feeders and distributes them to the outgoing feeders. In other words, it is a type of electrical junction in which all the incoming and outgoing electrical current meets. Thus, the electrical bus bar collects the electric power at one location. The bus bar system consists the isolator and the circuit breaker. On the occurrence of a fault, the circuit breaker is tripped off and the faulty section of the busbar is easily disconnected from the circuit. The electrical bus bar is available in rectangular, cross-sectional, round and many other shapes. The rectangular bus bar is mostly used in the power system. The copper and aluminium are used for the manufacturing of the electrical bus bar. The most common of the bus-bars are 40×4mm (160 mm 2 ); 40×5 mm (200 mm 2 ) ; 50×6 mm (300mm 2 ) ; 60×8 mm (480 mm 2 ) ; 80×8 (640 mm ...

 Transition capacitance (CT): A capacitor has two metal plates and an insulating material (dielectric) between them. The metal plates allow electric current, but the dielectric does not. It only allows an electric field. When voltage is applied, charges collect on the plates but cannot cross the dielectric. These trapped charges create an electric field, which stores electric charge. The ability to store charge is called capacitance .Capacitance increases when plate size is larger and decreases when the distance between plates is larger.  A reverse biased p–n junction diode acts like a capacitor. The p-type and n-type regions act as the plates. The depletion region acts as the dielectric. Charges in the depletion region do not move, but they create an electric field and store charge. This creates junction (transition) capacitance . When reverse voltage increases, the depletion region becomes wider. Wider depletion region means less stored charge. So, capacitance decreases whe...

  PN Junction Diode  1. Basic Concept A PN junction diode is formed by joining p-type and n-type semiconductor materials into a single crystal. Its key property is unidirectional conduction : it conducts current mainly in one direction and blocks it in the other. 2. Doping and Charge Carriers P-type Semiconductor Doped with trivalent impurities (Boron, Gallium) Majority carriers: holes Minority carriers: electrons N-type Semiconductor Doped with pentavalent impurities (Phosphorus, Arsenic) Majority carriers: electrons Minority carriers: holes 3. Formation of the PN Junction When P-type and N-type materials are joined: 3.1 Diffusion Process Electrons diffuse from N → P Holes diffuse from P → N They recombine near the junction 3.2 Depletion Region Mobile charge carriers disappear near the junction Leaves behind fixed ions This region is called the depletion layer 3.3 Electric Field Formation Positive ions on N-side...

Current flows from a high voltage point to a low voltage point because of the potential difference . Electrical polarity describes the direction of this current flow. In a DC system, one pole is always positive, and the other is negative, so the current flows in one direction. In an AC system, the terminals change polarity periodically, changing the direction of the current. We use dot convention to identify the voltage polarity of the mutual inductance of two windings. The two used conventions are: If a current enters the dotted terminal of one winding, then the voltage induced on the other winding will be positive at the dotted terminal of the second winding. If a current leaves the dotted terminal of one winding, then the polarity of the voltage induced in the other winding will be negative at the dotted terminal of the second winding. Distribution transformers need to operate continuously and handle high demand during peak times. To manage this, we connect transformers i...

  Torque in a 3 phase induction motor  is determined by three key factors: Firstly the magnitude of rotor current, secondly the flux which interact with the rotor of three phase induction motor and is responsible for producing emf in the rotor part of inuction motor, lastly the power factor of rotor of the three phase induction motor. By integrating these factors, we derive the torque equation as follows: Where, T is the torque produced by the induction motor, φ is flux responsible for producing induced emf, I 2 is rotor current, cosθ 2 is the power factor of rotor circuit. The flux φ produced by the stator is proportional to stator emf E 1 . i.e φ ∝ E 1 We know that transformation ratio K is defined as the ratio of secondary voltage (rotor voltage) to that of primary voltage (stator voltage). Rotor current I 2 is defined as the ratio of rotor induced emf under running condition , sE 2 to total impedance, Z 2 of rotor side, and total impedance Z 2 on ...