The series motor has an appropriate speed-torque feature which is ultimately used for the purpose of railway service. Whereas the D.C. motor is a complete reasonable package for satisfaction because of its working procedure and is mostly-utilized for running the street railway cars and trolley coaches.This becomes even more appropriate and cost-effective to transport control and helps in the transformation of A.C voltages systems in contrast to the direct currents that proceeds the progress of an A.C. motor. This also initiates the practice of some of the noteworthy vapor-rod electrifications.
Working principle. An A.C. series motor works in similar principle to the D.C. motor. Both the field and body interrelated in the same as the D.C. motor.
When any discontinuous. m.f. is experimented to the terminals and the framework spiraling and the fields are associated in series. The body current and field stability converse at the same time at every half of the cycle, keeping the path of the torque undisturbed. The torque is vivacious. However, its mediocre value is similar to that of ther.m.sflux value and also current of any D.C. motor. The Motor connections, the direction of torque, for two consecutive half cycles are represented in the Fig. 18. When the bodywork core and the field faces short saturation levels, then the air-break flux will roughly be proportionate with current and also torque will nearly be relational to the current aligned.
However, all these things are theoretically possible to function commencing on an A.C. sequence motor up to D.C. circuit. To convert it into reality the following mechanical variations must have been made to make the motor a rational and resourceful machine:
- The whole magnetic circuit must have a plastic-coated body, and the components must be with small iron loss coefficient. This is what the parts of transformers must be.
- The field course is deliberated for much less substantial reactance compared to any similar D.C. motor area just to lessen the reactance drop of voltage of the area to maintain a minimum power of the engine.
- A disseminated reimbursing coiling is compulsory to lessen the sensitivity of the body work coiling by decreasing the escape flux and to nullify the cross-magnetizing out come of the framework ampere shots.
The reimbursing coiling might be associated in chains with sequence fields and windings in the armature, else it might have short-circuit issues for itself and accept its abrupt change in voltage by individual action. Since it is coupled with another armature cross-field as represented in the Fig. 19. In the first instance, the motor is conductively remunerated, whereas in the latter case, the engine is inductively rewarded. Conductive reimbursement is compulsory for the motors which are responsible for both the procedure in A.C. and D. C. circuits.