Permanent Magnet DC (PMDC) Motor – Construction, Working and Application

In Permanent Magnet DC Motor or PMDC Motor, permanent magnet is used to create the working flux in the air gap instead of field winding. The construction of rotor is same as that of the Conventional DC Motor i.e. rotor of PMDC Motor consists of armature core, armature winding and commutator. Generally, there are two … Read more Permanent Magnet DC (PMDC) Motor – Construction, Working and Application

Why DC Series Motor has High Starting Torque?

DC Series Motors are widely used for the purposes requiring high starting torque like in Hoist, Crane, Electric Traction etc. In this post we will discuss the reason behind the high starting torque of DC Series Motor. For any DC motor, torque is directly proportional to the flux and armature current i.e. Ƭ = KaØIa  … Read more Why DC Series Motor has High Starting Torque?

What will happen if DC Motor run at a Higher RPM than the Rated RPM?

This may come in our mind that what exactly will happen if we operate a DC Motor at a speed more than the rated speed. In fact, the thermal capacity of the motor decides at what speed it can run and for how long. There is always a safety factor considered in the design which … Read more What will happen if DC Motor run at a Higher RPM than the Rated RPM?

Ward-Leonard Method of Speed Control

As discussed in the previous post “Speed Control of DC Motor”, speed of DC Motor can be controlled by varying the terminal voltage Vt of the DC Motor. Ward-Leonard Method is the application of this principle where the terminal voltage Vtof DC Motor is varied to control the speed of DC Motor. Ward-Leonard Method of … Read more Ward-Leonard Method of Speed Control

Speed Control of DC Motor by Varying Field Flux

In previous post “Speed Control of DC Motor” we discussed the method of speed control of DC Motor by Armature Circuit Resistance Control Method. In this post we will discuss the method of speed control of DC Motor by varying the Field Flux which is known as Field Weakening Method. By Field Weakening Method of … Read more Speed Control of DC Motor by Varying Field Flux