Power Electronics

Definition: Buck Converter is a type of chopper circuit that is designed to perform step-down conversion of the applied dc input signal. In the case of buck converters, the fixed dc input signal is changed into another dc signal at the output which is of lower value. This means it is designed to produce a dc signal as its output that possesses a lower magnitude than the applied input. It is sometimes called Step-down DC to DC Converter or Step-down Chopper or Buck Regulator. Introduction We … [Read more...] about Buck Converter

Definition: The circuits that are designed to directly convert fixed dc voltage into adjustable dc voltage are called Chopper Circuits. It is also known as dc to dc converter or dc chopper. Choppers are considered to be dc equivalent to ac transformers, the reason for the same is that similar to the transformers, choppers hold the ability to step up or step down the fixed dc input voltage. It is known to be a static power electronics device built with an approach to increase or decrease the … [Read more...] about Chopper Circuit

Definition: Current Source Inverter is a type of inverter circuit that changes the dc current at its input into equivalent ac current. It is abbreviated as CSI and sometimes called a current fed inverter. Here the input provided to the circuit is a stiff dc current source rather than dc voltage source. In CSI, the input voltage is kept invariable and the amplitude of output voltage does not show dependency on load. But the waveform representation and the magnitude of the current flowing … [Read more...] about Current Source Inverter

Definition: Voltage Source Inverter abbreviated as VSI is a type of inverter circuits that converts a dc input voltage into its ac equivalent at the output. It is also known as a voltage-fed inverter (VFI), the dc source at the input of which has small or negligible impedance. In a VSI, battery banks are considered to be the simplest form of dc voltage source which is a combination of multiple cells in series and parallel combinations. However, sometimes photovoltaic cells are also used as a … [Read more...] about Voltage Source Inverter

Definition: The word dual means two. Dual converters are defined as an antiparallel arrangement of two entirely controlled converters that operate in all four quadrants of the V-I plane. It is such a device that performs two simultaneous conversions. In a dual conversion system, the two converters out of which one acts as rectifier while another acts as inverter are connected to a common dc load. Thus is called so. What are Converters? A power electronic converter or simply a converter is … [Read more...] about Dual Converters

A sub-classification of forced commutation technique in which the main thyristor is commutated by application of reverse voltage along with the use of an auxiliary thyristor is known as Class D Commutation of Thyristor. As it uses reverse-biased voltage to turn the thyristor off it is also referred to as Voltage Commutation. Sometimes it is called parallel capacitor commutation and the reason for this is that here when the auxiliary thyristor is turned on then to turn off the main thyristor, … [Read more...] about Class D Commutation of Thyristor

A sub-classification of forced commutation in which the device is commutated by transferring the load current of the main thyristor to another thyristor in the circuit is Class C Commutation of the Thyristor. Another name for this type of commutation is complementary commutation. This commutation technique shows high reliability and suits operations at frequencies below 1000 Hz. What is Commutation of Thyristor? Commutation of Thyristor defines the process to turn the thyristor off. We have … [Read more...] about Class C Commutation of Thyristor

Class B commutation of thyristor is another type of forced commutation technique that is used to turn off the SCR. In this commutation technique, the device gets turned off by building reverse current in a gradual manner from cathode to anode. Thus, is also referred to as current commutation or resonant pulse commutation. It is a forced type of self-commutation of SCR that makes use of resonating LC circuits. Basics of Commutation of Thyristor Previously we have discussed that unlike the … [Read more...] about Class B Commutation of Thyristor

Class A commutation of thyristor is a type of forced commutation and is also referred to as Load Commutation. It is one of the widely used commutation techniques that mainly find applications in high-frequency operations. Previously we have discussed that commutation of thyristor corresponds to turning the SCR off. Let us have a brief idea about- Commutation Techniques of Thyristor We have discussed thyristors that even after being in forward biased condition, the thyristor does not conduct … [Read more...] about Class A Commutation of Thyristor

The word commutation corresponds to an act of transferring current from one path to another. Thyristor Commutation refers to the process of turning the thyristor off. There are several ways utilizing which the thyristor gets commutated which is known as thyristor commutation techniques. We know that once a thyristor gets turned on after the application of gate pulse then even after the removal of gate pulse, current continues to flow through the device. This state is known as forward … [Read more...] about Thyristor Commutation Techniques