Single Phase Full Bridge Inverter

Single Phase Full Bridge Inverter:

In this inverter, number of thyristors and diodes is twice of that in a half-bridge inverter. It consists of four thyristors and four diodes.

What is Switching Circuit?

What is Switching Circuit?: 

The switching circuit essentially consists of a switch and an associated circuitry. The switch is the most vital part of the switching circuit

Transistor as a Switch Circuit Diagram and Working

Transistor as a Switch Circuit Diagram and Working:

Figure shows the output characteristics of a typical transistor for a CE configuration. The dc load line for a given collector supply voltage VCC and collector resistance RC is drawn on the output characteristics.

Switching Characteristics of Power MOSFET

Switching Characteristics of Power MOSFET:

Switching Characteristics of Power MOSFET:

witching Characteristics of Power MOSFET have the advantage of switching a large current off faster than a BJTs can because a power MOSFET does not have minority carriers.

Multivibrator definition and Types (Astable, Monostable and Bistable)

Multivibrator definition and Types (Astable, Monostable and Bistable):

Multivibrator definition and Types:

A multivibrator is basically a two stage R-C coupled amplifier with positive feedback from the output of one amplifier to the input of the other

Astable Multivibrator Definition and its Working

Collector Coupled Astable Multivibrator:

Collector Coupled Astable Multivibrator:

It is essentially a two-stage R-C coupled amplifier with the output of first stage coupled to the input of second stage; and the output of second stage coupled to the input of the first stage.

Read More on this Collector Coupled Astable Multivibrator below…

Monostable Multivibrator – Operation, Types and Application

Monostable Multivibrator – Operation, Types and Application: Types of Monostable Multivibrators:

Collector-coupled monostable multivibrator

Emitter-coupled monostable multivibrator.

Bistable Multivibrator – Working and Types

Bistable Multivibrator – Working and Types:

A bistable multivibrator, as its name implies, has two stable states. It can stay in either of the two states indefinitely (as long as dc power supply remains on).

Commutating Capacitor in Bistable Multivibrator or Speed up Capacitor

Commutating Capacitor in Bistable Multivibrator or Speed up Capacitor:

Commutating Capacitor in Bistable Multivibrator is also called as Speed up Capacitor. Whenever a triggering pulse is applied to change the bistable state from one bistable state to another, it is necessary that the transition period should be minimum and it should require minimum but finite amount of energy.

Triggering in Digital Electronics | Types

Triggering in Digital Electronics | Types: 

Triggering in Digital Electronics is the process of applying an external signal to induce transition from one state to another.

Blocking Oscillator – Definition, Operation and Types

Blocking Oscillator – Definition, Operation and Types:

Types of Blocking Oscillator:

1.Monostable Blocking Oscillator

2.Astable Blocking Oscillator

Op Amp IC 741 Pin Diagram and its Working

Op Amp IC 741 Pin Diagram and its Working: 

The schematic diagram and Op Amp IC 741 Pin Diagram is shown in Fig. 33.4 (a) and in Fig. 33.4 (b). It is not necessary to understand every detail about the circuit design and its operation in order to be able to use the IC. What must be understood is the correct terminal connection and biasing for the input terminal, as well as the limitations on supply voltages, signal levels, and external load. In the schematic diagram shown in Fig. 33.4 (a), the base leads of Q1 and Q2 are connected to the pins on the IC unit and serve as the two inputs of the op-amp. Q1 and Q2 transistors form a differential amplifier circuit. Transistors Q12 and Q13 constitute a complementary emitter follower output stage. The output is taken at the emitter of transistors Q12 and Q13. This push-pull configuration allows the op-amp to have a very low output impedance, which is analogous to a voltage source having a very small internal resistance.

CMRR of Op Amp Formula (Common Mode Rejection Ratio)

CMRR of Op Amp Formula (Common Mode Rejection Ratio):

A measure of this rejection of signals common to both inputs is referred to as the CMRR of Op Amp and a numerical value is assigned, which is called the common-mode rejection ratio (CMRR).

Op Amp Differential Amplifier Circuit Diagram and its Operation

Op Amp Differential Amplifier Circuit Diagram and its Operation: 

A circuit that amplifies the difference between two signals is called a difference or Op Amp Differential Amplifier.

Differential Amplifier with two Op Amps

Differential Amplifier with two Op Amps: 

The gain as well as input resistance of the differential amplifier can be increased by using two op-amps. The characteristics of such an amplifier are identical to those of a noninverting amplifier.

Differential Amplifier With Three OP Amp

Differential Amplifier With Three OP Amp: 

Differential Amplifier With Three OP Amp consists of two stages—one formed by op-amps A1 and A2 and second by op-amp A3.

Read More on this Differential Amplifier With Three OP Amp below…

Differential Input and Differential Output Amplifier

Differential Input and Differential Output Amplifier: 

The differential input and differential output amplifier is widely employed as a pre-amplifier and in driving push-pull arrangements.

Clamping Circuit Theorem

Clamping Circuit Theorem:

According to clamping circuit theorem, under steady-state conditions, the ratio of area in forward direction Af to that of reverse direction Ar of output voltage is equal to the ratio of diode forward resistance Rf to resistance R connected across diode.

Band Reject Filter Circuit

Band Reject Filter Circuit: 

In this Band Reject Filter Circuit, frequencies are attenuated in the stop band and passed outside it.

Harmonic Distortion Analyzer

Harmonic Distortion Analyzer:

A Harmonic Distortion Analyzer measures the total harmonic power present in the test wave rather than the distortion caused by each component. Read More...

Three Phase AC Voltage Controller

Three Phase AC Voltage Controller: 

To control the current and voltage of three phase loads, Three Phase AC Voltage Controller are required. The single phase controller described previously can be introduced singly in each phase or line, to form a Three Phase AC Voltage Controller.

Three Terminal IC Voltage Regulators – Block Diagram

Three Terminal IC Voltage Regulators – Block Diagram:

The latest generation of IC voltage regulators has devices with only three pins: one for the unregulated input voltage, one for the regulated output voltage, and one for ground.

FET as a Voltage Variable Resistor (VVR)

FET as a Voltage Variable Resistor (VVR):

FET is a device that is usually operated in the constant-current portion of its output characteristics.

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Types of Solar Power Plant

Types of Solar Power Plant:

Types of solar power plant are

Solar pond electric power plant

Low temperature solar power plant

Medium temperature systems using focusing – collector

High temperature systems – [solar farm and solar power plant]

Successive Approximation Type DVM

Successive Approximation Type DVM:

The Successive Approximation Type DVM principle can be easily understood using a simple example; the determination of the weight of an object. By using a balance and placing the object on one side and an approximate weight on the other side, the weight of the object is determined.

Multistage Impulse Generator Circuit

Multistage Impulse Generator Circuit:

Components of a Multistage Impulse Generator Circuit

1.d.c. Charging Set

2.Charging Resistors

3.Generator Capacitors and Spark Gaps

4.Wave-shaping Resistors and Capacitors

5.Triggering System

6.Voltage Dividers

7.Gas insulated impulse generators

Switching Characteristics of Power MOSFET

Switching Characteristics of Power MOSFET:

Power MOSFET is an enhancement mode device modified to handle much large currents and voltages than a conventional MOSFET.

Tidal Power Plant – Types and Working Principle

Tidal Power Plant – Types and Working Principle:

The following are the components of a tidal power plant

1.The dam or dyke (low wall) to form the pool or basin.

2.Sluice ways from the basins to the sea and vice versa.

3.The power house.

Closed Loop Speed Control of DC Motor

Closed Loop Speed Control of DC Motor:

The Closed Loop Speed Control of DC Motor schemes are provided with inner current control loop in order to limit the current within a safe limit and also to accelerate and decelerate the drive at the maximum permissible current and torque during transient operations.

Magnetic Tape Recorder Working Principle

Magnetic Tape Recorder Working Principle:

A magnetic tape recorder consists of the following basic components.

Recording Head

Magnetic Head

Reproducing Head

Tape transport mechanism

Conditioning devices

Pulse and Square Wave Generator Block Diagram

Pulse and Square Wave Generator Block Diagram:

Pulse and Square Wave Generator are used as measuring devices in combination with a CRO. They provide both quantitative and qualitative information of the system under test.

Sweep Frequency Generator – Block Diagram and its Workings

Sweep Frequency Generator – Block Diagram and its Workings:

A Sweep Frequency Generator is a special type of signal generator which generates a sinusoidal output whose frequency is automatically varied or swept between two selected frequencies. One com­plete cycle of the frequency variation is called a sweep.

Three Phase Semi Converter feeding Separately Excited DC Motor

Three Phase Semi Converter feeding Separately Excited DC Motor:

In a three Phase Semi Converter, the ripple frequency of the motor terminal voltage is higher than that in the single-phase converter, as a result the filtering requirements for smoothing out the motor current are less and the current is mostly continuous.

Unbalanced Three Phase Circuit Analysis

Unbalanced Three Phase Circuit Analysis:

Types of Unbalanced Loads

Unbalanced delta-connected load

Unbalanced three-wire star-connected load, and

Unbalanced four-wire star-connected load.

First Order Low Pass Butterworth Filter

First Order Low Pass Butterworth Filter:

The first order low pass butterworth filter is realized by R-C circuit used along with an op-amp, used in the noninverting configuration. The circuit diagram is shown in Fig. 2.74. This also called one pole low pass butterworth filter.

Precision Full Wave Rectifier

Precision Full Wave Rectifier:

The Precision Full Wave Rectifier circuits accept an ac signal at the input, inverts either the negative or the positive half, and delivers both the inverted and noninverted halves at the output

Second Order Low Pass Butterworth Filter

Second Order Low Pass Butterworth Filter: 

The practical response of Second Order Low Pass Butterworth Filter must be very close to an ideal one. In case of low pass filter, it is always desirable that the gain rolls off very fast after the cut off frequency, in the stop band.

Negative Phase Sequence Relay

Negative Phase Sequence Relay: 

A negative phase sequence relay (or phase unbalance) is essentially provided for the protection of generators and motors against unbalanced loading that may arise due to phase-to-phase faults.

Voltage Balance Differential Relay

Voltage Balance Differential Relay: 

In this voltage balance differential relay arrangement, two similar current transformers are connected at either end of the system element

Mho Type Distance Relay – Working and Characteristics

Mho Type Distance Relay – Working and Characteristics: 

Mho relay is a high speed relay and is also known as admittance relay. It is also sometimes called an angle impedance relay.

Thermal Relay Construction and Working Principle

Thermal Relay Construction and Working Principle: 

Thermal Relay can operate on the principle of thermal effect of electric current. It consists of bimetallic strips which are used in small

Permanent Magnet Moving Coil Relay

Permanent Magnet Moving Coil Relay:

In this relay, the coil is free to rotate in the magnetic field of a permanent magnet. The torque is developed by the interaction between the field of the permanent magnet and the coil field developed due to flow of actuating current in the coil.

Electromagnetic Induction Relay – Structure and Working Principle

Electromagnetic Induction Relay – Structure and Working Principle:

Electromagnetic induction relay operate on the principle of induction motor and are widely used for protective relaying purposes involving a.c. quantities. They are not used with d.c. quantities owing to the principle of operation.

Classification of Relays

Classification of Relays: 

The protective relay may be defined as an electrical device interposed between the main circuit and the circuit breaker in such a manner that any abnormality in the circuit acts on the relay, which in turn, if the abnormality is of a dangerous character, causes the breaker to open and so to isolate the faulty element.

HVDC Circuit Breakers

HVDC Circuit Breakers:

Light duty dc circuit breakers have been in use since long. However, there is lack of suitable circuit breakers for HVDC systems. At present most of the HVDC systems are with two terminals and in a two terminal HVDC system, HVDC circuit breakers are not required because fault current can be controlled or eliminated by controlling the firing angle of the converters. In multi-terminal HVDC systems, the need of HVDC circuit breakers will arise.

Instrument Transformers – Definition, Types and Errors

Instrument Transformers – Definition, Types and Errors: 

AC type protective relays are actuated by current and voltage supplied by current and potential (or voltage) transformers, known as instrument transformers.

What is Short Circuit Current? – Definition and its Process

What is Short Circuit Current? – Definition and its Process: 

Whenever a short circuit current occurs in a power network, it causes heavy current to flow in the network.

Methods of Ventilation and Cooling of Electrical Machines

Methods of Ventilation and Cooling of Electrical Machines: It is necessary to provide suitable ventilation and cooling of electrical machines so that the temperature rise at any part of the machine

Types of Power Transmission Drives

Types of Power Transmission Drives: Various types of power transmission drives are namely, Direct Drive, Belt Drives, Rope Drive, Chain Drive, Gear Drive, Vertical Drive.