Interview question – Induction Motors

Here are the most frequently asked questions on Induction motors. This article aims to cover most of the interview questions on induction motors so as to prepare you to crack…

Interview Question – Variable frequency drives

Here are the most frequently asked interview questions on Variable frequency drives (VFD/VSD). This article aims to cover most of the interview questions on induction motors so as to prepare…

MOS Turn-Off Thyristor (MTO)

MTO stands for MOS turn-off thyristor. It is a high-power bipolar MOS thyristor that constitutes both MOSFET and Gate Turn-off thyristor (GTO). It was developed as a replacement for GTO. It…

Difference between Transistors and Thyristors

Transistors and thyristors are semiconductors switching devices. They are used for controlling current flow in circuits. They play a very important role in all power conversion devices. In this article…

The difference between kVA and kVAR

The difference between kVA and kVAR is pretty simple. "kVA" is the unit of apparent power whereas "kVAR" is the unit of reactive power. Before getting into the topic, we…

TRIAC – Operation, symbol, circuits & applications

A TRIAC or TRIode for Alternating Current is a three-terminal bidirectional thyristor, meaning that can conduct current in both directions when activated properly. It is used in AC switching applications.…

Surge Protection Device (SPD) | Surge protector

A surge protection device (SPD) or simply a surge protector is a device used to ensure protection against transient surges. It is used to protect the household and commercial applications…

Thyristors and their types

Thyristors are high-speed semiconductor switching devices that are made up of four layers of alternating p and n-type materials. They are used in AC/DC switching and AC power control applications.…

SCR – Silicon Controlled rectifier

A Silicon Controlled Rectifier (SCR) is a unidirectional semiconductor device that can be triggered into conduction by applying a positive gate current. It led to tremendous advancements in power semiconductor…

Transformer cooling methods

Transformers are the most efficient electric machine. A typical transformer is over 99% efficient. The small inefficiency is due to copper losses, core losses-hysteresis and eddy currents losses, stray and…