Home / Basic Electrical (page 3)

Basic Electrical

Power Factor Correction using Capacitor Bank

Power Factor Improvement

Power factor Ideally, all the supply voltage and current should be converted into true power in a load. When this is not a case, a certain kind of inefficiency occurs. The ratio of true power to apparent power is called the power factor of the load, \[\begin{matrix}   Power\text{ }Factor=\frac{true\text{ }Power}{Apparent\text{ …

Read More »

Apparent, Active and Reactive Power

This section covers basic concepts about apparent, active (real) and reactive power which is important ingredients in the analysis of a power system. Consider the general single-phase circuit with a sinusoidal voltage $v={{V}_{m}}sin\left( wt \right)$ applied. A current $i={{I}_{m}}sin(wt\pm \theta )$  results and is leading (θ is positive) for a capacitive …

Read More »

Maximum Power Transfer Theorem

Maximum Power Transfer Theorem Definition Maximum power transfer theorem states that maximum power output is obtained when the load resistance RL is equal to Thevenin resistance Rth as seen from load Terminals. Fig.1: Maximum Power Transfer Theorem Any circuit or network may be represented by a Thevenin equivalent circuit.  The Thevenin …

Read More »

Nodal Analysis or Node voltage Method

Nodal analysis or Node voltage method uses node voltages as circuit variables in order to analyze the circuit. The objective of this section is to obtain a set of simultaneous linear equations. However, unlike the mesh analysis method, the procedure developed in this section depends on the choice of certain …

Read More »

Mesh Current Analysis | Mesh Analysis

Two Loop Network

The mesh is a closed path which does not contain any other closed path within it. This section shows that a set of simultaneous linear equations can be written which describes the network. This set of equations depends on a choice of loop currents used in connection with Kirchhoff’s law. …

Read More »

Kirchhoff’s Voltage Law (KVL)

In order to present Kirchhoff’s voltage law, we must introduce the concept of a “loop”. Since energy must be conserved when a charge goes around a loop, the energy given up by the charge equals the energy it gains. The same energy-conservation principle would apply if you carried a rock …

Read More »

Kirchhoff’s Current law (KCL)

Kirchhoff's Current Law

For a given circuit, a connection of two or more elements is called a NODE. The particular circuit shown in figure 1 depicts an example of a node. Figure.1: Circuit for Kirchhoff’s Current Law We now present the Kirchhoff’s current law which is essentially the law of conservation of electric …

Read More »

RC Series Circuit Analysis | RC Time Constant

In the case of a resistive-capacitive (RC) series circuit, when the supply is first switched on the charging current is initially at its maximum level, then it gradually falls to zero. The capacitor voltage is zero at first and grows gradually to its maximum level. As with the RL Circuit, …

Read More »

Resistors in Series and Parallel

Resistors in Parallel

Resistance Resistance is defined as the measure of opposition to the motion of electrons due to their continuous collisions, with the atoms of the conductor. The unit of resistance is ohm. Let’s consider the conductor of cross-sectional area A and of length L as given below: The resistance of this …

Read More »

RL Series Circuit Analysis

When a resistive-inductive (RL) series circuit has its supply voltage switched on, the inductance produces an initial maximum level of counter-emf that gradually falls to zero. The circuit current is zero initially and grows gradually to its maximum level. The behavior of an RL series circuit is most easily understood …

Read More »

Superposition Theorem

Superposition theorem is stated as follows: The current is any circuit element or voltage across any element of a linear bilateral network is the algebraic sum of the currents or voltages separately produced by each source of energy. Simultaneous equations may be avoided in the solution of a complex network …

Read More »