## Load Test or Back to Back Test or Sumpner’s Test of Transformer

Load Test of a Transformer is basically carried out for determining the maximum temperature rise of the Transformer. However is not viable to conduct this test by connecting the secondary of the Transformer to rated load. In case of small Transformer, rated load can be...

## Stray Load Loss and Mechanical Loss in an Electrical Machine

Stray Load Loss: As we know that, when an electrical machine is loaded, load current flowing in the armature winding of the machine produces an mmf which distorts the space distribution of mmf produced or set up by the field winding in the air gap....

## How Space Harmonic in Rotating MMF wave Produces only Fundamental Frequency Voltage in Stator?

It is a well known fact that, space harmonic present in the rotating mmf wave in an uniform air gap Electrical Machine (Non Salient Pole machine) produces or generates only fundamental frequency voltage in the Stator winding of the machine. In this post we will...

## Why Number of Stator and Rotor Poles must be Equal for Production of Electromagnetic Torque?

This is very basic but important concept to understand Electrical Machine. It is well known fact that, the number of stator and rotor poles must be equal for the production of net Electromagnetic Torque. In this post we will discuss the reason behind this. Let...

## Concept of Electrical and Mechanical Angles & Synchronous Speed

Electrical and Mechanical angles are frequently used in the study of Electrical Machine theory and therefore it is very important to have a crystal clear concept of these two terms and the relationship between them. In this post we will also discuss about the Synchronous...

## Difference between Cylindrical and Salient Pole Rotor Synchronous Generator

We are quite familiar with Synchronous Generator or often called Alternator. There are mainly two types of Synchronous Generator from rotor construction point of view. The two main types of synchronous machine are Cylindrical Rotor and Salient Pole. Saliency simply means projection outward. Therefore from...

## Capacitor Split Phase Motors or Starting of Single Phase Induction Motor by Capacitor

We have already discussed about staring methods of Single Phase Induction Motor. If you miss that please read here, 1)     Revolving Field Theory of Single Phase Induction Motors 2)     Starting Methods of Single Phase Induction Motors The schematic diagram of Capacitor Split Phase Motor is...

## Starting Methods of Single Phase Induction Motors

As discussed in earlier post Revolving Field Theory of Single Phase Induction Motors, a single phase induction motor with main stator winding alone has no inherent starting torque as the main stator winding only produces stationary pulsating air gap flux wave. For the development of starting...