DC Machines

DC Machines:

Armature Control : Armature Control – The main requirement of this control scheme is a variable voltage supply to …


Armature Reaction : When the armature of a dc machine carries current, the distributed armature winding produces its own …


Braking of DC Motors : Braking of DC Motors – Controlled slowing or stopping of a motor and its driven …


Characteristics of DC Generators : With the advent of silicon-controlled rectifiers, the importance of the dc machine as a …


Characteristics of DC Motors : The power of the dc motor lies in its versatility and ease with which …


Commutation : One coil each under an adjoining pole-pair is connected between adjacent commutator segments in a lap-wound dc …


Compensating Winding : Compensating Winding – It was seen in Sec. 7.5, Fig. 7.9(c) that armature reaction causes the …


Compound Generator : The causes of voltage drop in the terminal voltage from no-load to full-load in a shunt …


DC Machine Applications : DC Machine Applications – Whenever the application of any machine is considered, its operating characteristics …


DC Machine Circuit Model : The parallel paths of dc machine armature are symmetrical and each has an induced …


DC Machine Dynamics : The DC machines are quite versatile and are capable of giving a …


Efficiency and Testing : Efficiency of dc Machines Machine efficiency, in general, has been discussed in Sec. 5.9. The approach …


EMF and Torque : EMF and Torque – It was shown in Sec. 5.2 (Fig. 5.14 (a)) that in …


Hopkinsons Test : This is a regenerative test in which two identical dc shunt machines are …


Introduction of DC Machine : Introduction of DC Machine is constructed in many forms and for a variety of …


Magnetization Characteristics : The emf and torque equations, and power balance has been considered so far. The consideration of …


Methods of Excitation : The performance characteristics of a dc machine are greatly influenced by the way in which …


Predetermination of External Characteristic : The Predetermination of External Characteristic of a shunt generator can be predetermined from a …


Rheostatic Control : Series armature-resistance control Here the applied armature voltage is varied by placing an …


Self Excitation : Rather than arranging a separate dc source for excitation purposes, practical generators are always excited from …


Series Motor : Figure 7.43 shows the connection diagram of a dc series motor. The speed for this motor …


Series Parallel Control : Here two identical motors are coupled together mechanically to a common load. Two speeds at …


Shunted Armature Control : Shunted Armature Control -It is a variation of rheostatic control. As is obvious from Fig. …


Speed Control of DC Motors : The Speed Control of DC Motors are in general much more adaptable speed …


Starting of DC Motors : At the time of starting (n = 0), the …


Ward Leonard Method of Speed Control : Ward Leonard Method of Speed Control is combined armature and field control …


Updated: April 30, 2020 — 3:14 pm