Synchronous Generator Concepts

The generator has elements extremely relevant to its operation in a suitable way, such as the rotor, referring to the rotating part of the machine. It can consist of a package of sheets of ferromagnetic material held in a winding formed by copper conductors, called field winding, with the function of generating a constant magnetic field, in the same way as in the case of the direct current generator to interact with the field produced by the stator winding.

It is important to note that its synchronous name is due to the fact that this machine is capable of operating with a constant speed of rotation synchronized with the frequency of the alternating electric voltage applied to its terminals. This means that, due to the rotational movement between the rotating field and the rotor, it is known as a synchronous machine, since it must be taken into account that it promotes synchronism between the stator and rotor fields. In this way, this generator is considered one of the most important types of rotary electric machines, allowing the conversion of energy when operated as a generator or as a motor.


Smooth Polo Rotor

Plain-rotor rotors are identified by having a uniform cylindrical shape and bundle of unsegmented, single-piece or laser-cut plates, usually attached to the shaft by “ribs”. The poles are constructed by grouping the sheet of the package and therefore are integral with the package of plates of the rotor and are not detachable. The field coils are constructed of insulated copper wires and secured in grooves of the sheet pack, with coil configuration being allocated without turning the poles at the periphery of the rotor. The bobbin heads are fastened by means of bandage or shaped steel sleeve on the coils.

The cage of this type of rotor is also symmetrically distributed. This rotor composition exhibits high symmetry, masses evenly distributed over the entire length of the rotor, making it cylindrical, compact and robust. Due to these peculiarities the synchronous motors with smooth poles rotor are most often used in machines of high rotation. Due to this rotor fabrication, the air gap is almost constant throughout the rotor circumference, with possible paths for equivalent magnetic flux through the interpolar regions, where there are also plates, which allows greater flow dispersion.