Power Electronics

Switching Characteristics of IGBT is basically the graphical representation of behavior of IGBT during its turn-on & turn-off process. The turn-on time is defined as the time between the instant of forward blocking to forward conduction mode. Here, forward conduction means the device conducts in forward direction. Turn-on time (ton) is basically composed of two … Read more

VI characteristics of IGBT is the graphical relationship between collector current and collector-emitter voltage (VCE) for different values of gate-emitter voltages. It is basically a plot of collector current (IC) versus collector-emitter voltage for various values of gate-emitter voltage (VGE). VI characteristics of IGBT is also known as Static or Output Characteristics. Let us now … Read more

This article explains IGBT, its symbol, construction and working principle with relevant structure and circuit diagrams. What is IGBT? IGBT (Insulated Gate Bipolar Transistor) is a three terminal power switch having high input impedance like PMOSFET and low on-state power loss as in BJT (Bipolar Junction Transistor). Thus, IGBT is a combined form of best … Read more

This article explains the UPS, its application, historical background, types and working principle of UPS with their schematic diagram. Definition: A UPS is a device which provides an uninterruptable power supply so as to maintain the continuity of supply in case of power outage. UPS stands for Uninterruptable Power Supply. Requirement of UPS: There are … Read more

Integral Cycle Control is a strategy to control the output voltage of AC voltage controller. In this strategy, load is connected to the source for an integral number of cycle of input supply and then disconnected by switching off the supply for a further number of integral cycles. This strategy is also known as on-off … Read more

Single Phase AC Voltage Controller is a device which converts fixed single phase alternating voltage directly to a variable alternating voltage without a change in frequency. The input and output of the device is single phase. There are two types of single phase AC Voltage Controller: Single phase Half Wave and Single phase Full Wave. … Read more

Definition: AC Voltage Controller is a thyristor based device which converts fixed alternating voltage directly to variable alternating voltage without a change in frequency. AC Voltage Controller is a phase-controlled device and hence no force commutation circuitry is required.  Natural or line commutation is used. Phase control means that the phase relationship between the start … Read more

Step-down cycloconverter is a device which steps down the fixed frequency power supply input into some lower frequency. It is a frequency changer. If fs & fo are the supply and output frequency, then fo < fs for this cycloconverter. The most important feature of step-down cycloconverter is that it does not require force commutation. … Read more

A single phase to single phase cycloconverter is a type of cycloconverter whose input & output are single phase AC. The basic function remains the same i.e. frequency changing. A single phase to single phase cycloconverter may either be mid-point type or bridge type step-up or step-down cycloconverter. In this article, we will understand the … Read more

Step-up cycloconverter is a single phase to single phase device which converts input AC power at one frequency to output power at a different frequency. The output frequency is more than the input frequency for this cycloconverter. Single phase to single phase means that both the input power and output power are single phase. This … Read more