Induction Machine

Speed Control of Induction Motor: Stepless control of speed of induction motors cannot be carried out as efficiently and inexpensively as for dc motors. Various methods of Speed Control of Induction Motor can be visualized by consideration of the speed equation It is seen from this equation that there are two basic methods of speed […]

Crawling and Cogging in Induction Motor: Crawling and Cogging in Induction Motor – A squirrel-cage rotor may exhibit a peculiar behavior in starting for certain relationships between the number of poles and the stator and rotor slots. With the number of stator slots S1 equal to or an integral multiple of rotor slots S2, the

Starting Methods of Induction Motor: Starting Methods of Induction Motor – At the time of starting the motor slip being unity, the load resistance with reference to the approximate circuit model of Fig. 9.23 is meaning thereby that short-circuit conditions prevail. Therefore, the motor current at starting can be as large as five to six

Torque Slip Characteristics of Induction Motor: The expression for Torque Slip Characteristics of Induction Motor (T(s)) is easily obtained by finding the Thevenin equivalent of the circuit to the left of ab in Fig. 9.12. The circuit then reduces to Fig. 9.13 in which it is convenient to take VTH as the reference voltage. From

Air Gap Power in Induction Motor | Torque and Power Output Equation: Air Gap Power in Induction Motor – The circuit model is shown in Fig. 9.10. The power crossing the terminals ab in this circuit is the electrical power input per phase minus the stator loss (stator copper-loss and iron-loss) and hence is the

Approximate Circuit Model of an Induction Motor: An Approximate Circuit Model of an induction motor, which results in considerable computational ease in analysis, is obtained by shifting the shunt branch in Fig. 9.8(a) to the input terminals as shown in Fig. 9.9. This step is not so readily justified as in a transformer owing to the

Induction Motor Equivalent Circuit: Induction Motor Equivalent Circuit – The behavior of the induction machine was studied in terms of the basic field phenomenon. The attempt here was purposely focused on the transformer analogy of induction motor. Certain facts established so far are summarized below: 1. where E2 = standstill rotor emf. Further I’2 flows

Principle of Operation of Induction Motor: The Principle of Operation of Induction Motor in Figure 9.4 shows the cross-sectional view of an induction motor. The stator is fed from a 3-phase supply of voltage V/phase and frequency f Hz. The rotor is wound 3-phase for as many poles as the stator and is short-circuited. It

Construction of Induction Motor and Types of Rotor in Induction Motor: The stator of an Construction of Induction Motor is similar to that of a synchronous machine and is wound for three phases, modem practice being to use the two-layer winding. Figure 9.1 shows the stator of an induction motor. Types of Rotor in Induction