Speed Control of DC Series Motor - Flux & Rheostatic Control

In a dc motor, speed will depend on armature current and field voltage. So to control dc motor speed, field voltage or armature current should be changed. In a dc series motor or universal motor, the speed is indeterminate and i…

Power Flow Diagram & Power Developed by Synchronous Motor

The phasor diagram of a synchronous motor is shown below. From the phasor diagram, let, V = Supply voltage/phase I a = Armature current/phase R a = Armature resistance/phase α = Load angle Φ = Power factor angle. Input Power …

EMF Equation of a Synchronous Generator or Alternator

We know that in a synchronous generator or alternator when the conductors of the rotor cuts the alternating magnetic flux lines produced by the stator or field winding an EMF will induce in the rotor conductors (according to the …

V Curves and Inverted V Curves of Synchronous Motor

The performance characteristics of a synchronous motor are obtained by v-curves and inverted v-curves. Synchronous machines have parabolic type characteristics (the graph drawn is in the shape of parabolic). If the excitation i…

Synchronous Condenser and Power Factor Correction

Synchronous Condenser or Synchronous Capacitor : If a synchronous motor is on no-load and over-excited (E b > V) then the current drawn by it leads the voltage by nearly 90°. The phasor diagram of the motor at no-load is sh…

Starting Methods of Synchronous Motor

A device that converts electrical energy into mechanical energy running at synchronous speed is called Synchronous Motor . Its speed is constant irrespective of load. It is a doubly excited machine because its field winding is ex…

Construction Details of Synchronous Motor

As there is no constructional difference between dc generator and dc motor, similarly, there is no difference between the construction of a synchronous motor and a synchronous generator (alternator). The construction of a synch…

Efficiency and Power Flow Diagram of Induction Motor

Power Transfer Stages of Induction Motor : An induction motor converts electrical power supplied to it into mechanical power. The various stages in this conversion are called power transfer stages in an induction motor. The 3-ph…

Induction Motor Applications

Most of the motors used for household and commercial purposes are induction motors. The use of an induction motor as an induction generator is insignificant. An induction motor has nearly constant speed motor characteristics. Oth…

No Load Test of Induction Motor

This test is similar to the no-load test performed on a transformer. The purpose of this test is to determine the no-load losses , no-load power factor, and constants R o and X o of the equivalent circuit. The no-load losses i…

Starting Methods for 3-Phase Induction Motor and Comparison

The various types of starters used for starting a 3-phase induction motor are, Full Voltage Starting, Direct-on-line (DOL) starter (full voltage starting). Reduced Voltage Starting, Autotransformer starter. Star-delta starter (re…

Load More
Completed