ABSTRACT

A comparison of a transfer field machine (TFM) and a polyp-phase induction machine (IM) is presented in this paper. Despite the fact that the two machines are from two different classes of machines and have very different physical configurations, they have identical torque – slip relationships. The transfer field machine, on the other hand, has a synchronous speed of o/2, or one-half that of the induction machine. In both the auxiliary winding of a transfer field machine and the rotor of an induction machine, the induced electromotive force (e.m.f) as well as the frequency of this induced e.m.f is proportional to slip. Both machines’ self inductance matrices are derived, and both are demonstrated to be independent of rotor angular position. The mutual coupling inductance is, however, dependent on the rotor angular position in both circumstances. The difference between the direct and quadrature-axes reactances is also important for the transfer field machine, in addition to rotor angle dependence. As a result of the rotor pole –axis attempting to align with the axis of highest flux, the machine creates reluctance torque. Induction machines, on the other hand, work by aligning fields, with the rotor’s rotating magnetic field attempting to catch up with the stator’s. The transfer field machine had lower draw out and starting torque, as well as lower efficiency, in steady-state performance than the induction machine. In dynamic mode, both machines’ torque versus speed characteristics are displayed.

CHAPTER ONE
INTRODUCTION
Induction machine theory is a well-known and well-established concept. The stator and the rotor are the two main components of an induction machine. A rotating magnetic field is created when an a.c voltage is applied to the terminals of the stator windings. By electromagnetic induction (transformer action), this revolving magnetic field produces an electromotive force (e.m.f) in the rotor, which in turn circulates current in the rotor, which is normally short-circuited. The current cycling in the short-circuited rotor produces a spinning magnetic field, which now interacts with the stator’s revolving magnetic field. This interaction results in a torque, which is responsible for the machine’s spin. Because the rotor magnetic field constantly lags behind the stator magnetic field, the induction machine is also known as an asynchronous machine. The discrepancy is known as the slip, and it is a crucial aspect of an induction machine’s operation. When an induction machine operates below synchronous speed, it is a motor; when it operates above synchronous speed, it is a generator. In fact, induction motors are the most common type of induction equipment.
As a technique of turning electric power to mechanical work, the induction motor is employed in a wide range of applications. It is, without a question, the electric power industry’s workhorse. Large multiphase induction motors are used in a variety of applications, including pumping, steel milling, and hoisting. Single-phase servo motors are commonly employed in position-follow-up control systems on a lesser scale, while single-phase induction motors are widely used in domestic appliances.

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