Single phase induction motor applications. Capacitor Start Induction Motor

Shaded Pole Induction Motor

Single phase induction motor applications

This capacitor is used to start the motor initially until it attains sufficient speed, after that the capacitor is disconnected by opening the switch. Let us consider the three instants, t1, t2, and t3 of alternating flux for an half cycle of the flux as shown in figure. The main winding has very low resistance and a high inductive reactance whereas the starting winding has high resistance and low inductive reactance. The induction machine responds to each magnetic field separately, and the net torque in the motor is equal to some of the torque due to each of the two magnetic fields. Later investigations have been conducted to work these type of motors under two-phase supply. These are used in fans, blowers, air conditioners, and compressors in refrigerators.

Next

Single Phase Induction Motor : Circuit Working and Applications

Single phase induction motor applications

This rotor current produces another flux called rotor flux required for the motoring action. And auxiliary winding connected in series with a capacitor and a starting switch. This motor consists of two capacitors of different value of capacitance for starting and running. This sequence will repeat for negative cycle too and consequently it produce moving magnetic field for every cycle from non shaded part of the pole to shaded part of the pole. When we open the starting switch it disconnects the starting capacitor from the auxiliary winding circuit. The direction of such emf can be obtained by Fleming's right-hand rule and this emf is in phase with the stator flux Φ s. Two-Value Capacitor Motor This motor has a cage rotor, and its stator has two windings namely the main winding and the auxiliary winding.

Next

Types of Single

Single phase induction motor applications

Because of simple construction, particularly for two poles Fig. Due to the current in the winding, some magnetic fields will be developed in the air gap. Winding Diagram It works on the principle of double field revolving theory where the current passing through the main winding will produce a fluctuating magnetic field. Starting torque is approximately 150 to 200% of full-load torque and starting current is high six to eight times the full-load current. But, the difference is that the torque produced by this motor is higher than split phase motor due to the use of capacitor. These are mostly used for low power but constant speed devices such as agricultural tools and machinery where three -phase supply are not available. The various applications are as follows:-.

Next

Shaded Pole Induction Motor

Single phase induction motor applications

According to this theory, any alternating quantity can be resolved into two rotating components which rotate in opposite directions and each having magnitude as half of the maximum magnitude of the alternating quantity. This torque is higher than a. We can find this motor in small cooling fans, in computers, inside refrigerators. This problem can be avoided by converting single phase motor into a two-phase motor temporarily in order produce revolving flux. The winding diagram is shown in the figure below.

Next

Shaded Pole Induction Motor

Single phase induction motor applications

Therefore, the relay opens and disconnects the auxiliary winding from the supply, making the motor runs on the main winding only. Both the windings are displaced by 90° in space like the windings in a two-phase induction motor. On smaller part, a single turn copper ring is fitted. Capacitor Run Motors: These have two windings, viz. Shaded Pole Motor The magnetic field induced in the main poles is induced into the shaded coil by means of an Induction Principle.

Next

Types of Single Phase Induction Motors

Single phase induction motor applications

This entire flux will appear on the iron core as the coil was wound on the core body. The Auxiliary winding is connected in parallel to a capacitor. Why Single Phase Induction Motor is Not Self Starting? Besides being cylindrical the rotor has slots all over its surface. Now if we provide the electric power to the three-phase windings of the stator then the current starts flowing in all three windings. This winding is designed for the operation of 75 % of synchronous speed and above. Since this shaded portion is short-circuited, the circulating current is produced in it in such a direction to oppose the main flux. These motors have very high starting torque up to 300% full load torque.

Next