Back EMF and its Significance in DC Motor
The back EMF momentarily opposes the armature voltage when the speed of the DC motor is changed, and thus, it limits the armature current. What … Read more
Machines
An electrical machine converts mechanical energy into electrical energy or vice versa. The transformer is also an electrical machine which transform the voltage without changing the frequency. We will discuss about the;
- DC Motor
- DC generator
- Induction Motor
- Transformer
- Electrical drives
- Alternator or synchronous generator
Transformer Over Fluxing Protection
The transformer over-fluxing protection protects the core from overheating caused by over-fluxing. The voltage and frequency ratio(v/f) is responsible for over-fluxing in the transformer. In … Read more
Over Fluxing in Transformer
How does the transformer work? The transformer has two coils wound around a common magnetic core. When an alternating voltage is applied to the primary … Read more
Why DC Series Motor should not be Started at No Load
The DC series motor attains dangerously high speed when we run it on no load. The main reason for overspeeding is that at no load, … Read more
Why is Star Delta Starter Preferred with an Induction Motor?
In star delta starting, the phase voltage is 58 % of the line voltage when the motor is first connected in the star connection. The … Read more
DC Shunt Motor : Construction, Speed Control & Characteristics
In this post, we will discuss the construction, speed control, and characteristics of DC shunt motors. CONSTRUCTION OF SHUNT DC MOTOR The field winding of … Read more
Why Are Rotor Bars Skewed in An Induction Motor?
What is Skewing of Rotor Slots? As shown in the above picture, the rotor bars of an induction motor are not parallel with the shaft, … Read more
Star Delta Starter | Working Principle, Power and Control Circuit Diagram
Introduction to Star Delta starter: Star delta starters are widely used to start a three-phase induction motor. In star-delta starting, the motor is first connected … Read more
Direct Online Starter (DOL Motor Starter): Circuit Diagram and Working Principle
Direct online starter is a method of starting an induction motor. The stator of the motor receives the full supply voltage in the DOL starter. … Read more
Why DC Series Motor is Used For Driving Heavy Loads?
The field and armature winding of the DC series motor are connected in the series and carry the same current. The torque of the DC … Read more