Types of single phase motor and its uses

Introduction: –

Single phase motor is also called fractional horse power motor. It means these motor’s power is very low or less than 1 hp. These motor’s speed is 1700 – 1800 rpm. As the name depicts it has a single phase and a neutral supply.

This type of motors is used in ceiling fan, table fan, stand fan, mixer, shaving machine, electric trimmer, vacuum cleaner, hair dryer, small robots etc. These have low power capacity, low torque, low performance in comparison to 3 phase Motors.

These types of motors are not self-starting.

single phase motor

Types of single-phase motors: –

Basically there are two types of single-phase motor.

  1. Non-commutator type motors
  2. Commutator type motors

Non-commutator type motors: –

In this section there are many types of motors which is given below.

  1. Induction motors
  2. Reluctance motors
  3. Unexcited synchronous motor.

Induction motors:-

There are following types of motors in induction motor sections.

  • Capacitor motor
  • Capacitor start motor
  • Capacitor start capacitor run motor
  • Shaded pole motor

Commutator motor:-

There are following types of commutator motors.

  • Series motor
  • Repulsion motor
  • Universal motor
  • Repulsion induction motor

Single phase induction motor:-

If we talk about structure of single phase induction motor, the structure of the motor is as three phase induction motor. But we can find out these differences.

First different is that single phase induction motor have one phase and a neutral wire.

Second one is that in the motor centrifugal switch is connected in the series of the starting winding.

The centrifugal switch disconnects the starting winding connection when the motor riches 70 to 80% of the full speed.

In single phase induction motor we use splited winding  to generate rotating magnetic field so that the motor can be self-start.

In this Motor, there are two types of winding first one is main binding which is also called stator winding and second one is starting winding or running winding or auxiliary winding.

Capacitor induction motor :-

This is the second form of single phase induction motor.
This motor has also two winding. And these two winding are displaced at 90 degrees to each other.
A capacitor is connected in series with starting winding. As picture shows. Rotor of the motor is squirrel cage type rotor. The current (Is) in starting winding is 90 degrees leading from the applied voltage. And the current (Im) is lagging by applied voltage.

Thus, we got adequate angle between starting winding current phaser and main winding current phaser. And we know that the phase difference between (Is) and (Im) is directly proportional to starting torque. So, we try to make more phase difference between Is and Im.

Shaded pole motor: –

Mostly, shaded pole motors are designed for fractional horse power (1/250 HP to 1/6 HP) at commercial level. This type of motor use where low starting torque needed. This motor is use in small fan, blower, hair dryer, electric watch etc.

This motor’s capacity performance is 5% to 35%. This motor is also use in toys.

Repulsion motor: –

This is a single-phase commutator motor. Single phase winding displaced on the stator of the motor. Rotor is slotted core type rotor. And on the rotor lap winding is displaced. This lap  winding is connected to commutator. Rotor of shaded pole motor is DC type rotor.

Uses of Repulsion motor: –

Repulsion motor is use in small cutter machine, compressor, freeze etc.

Repulsion induction motor: –

Sometimes, it is to identify between repulsion motor and repulsion induction motor. Repulsion induction motor’s rotor is squirrel cage type rotor. But this squirrel rotor have a regular winding also. And this regular winding is lap winding.

Uses of repulsion induction motor: –

This motor is use in –

  • Domestic fridge
  • Petrol pump
  • Compressor
  • Machine tools
  • Mixing machine
  • Lift hoist

Universal motor: –

As the name depicts, this motor works on AC and DC both. This motor is fractional horse power motor. This motor is series wound motor. And it has higher starting-torque. It has variable speed with changing load. Universal motor is like DC series motor. If we do some modification in DC series motor and make operatable on AC supply then it called Universal Motor.

This type of motor is not operatable on no load condition. Because at no load condition DC series motor or universal motor speed become dangerously high. And this is danger for human being and also motor’s foundation.

Also Read: –

What is multi plate or variable Capacitor

Uses of Universal motor: –

This motor is use in domestic apparatus like –

  • Sewing Machine
  • Table fan
  • Portable grinder
  • Drill Machine
  • Hair Dryer
  • Juicer
  •  Mixer

Reluctance motor: –

Reluctance motor has two types of structure. In first structure there is a split phase and a centrifugal switch is connected in auxiliary winding. This structure is just like single phase induction motor. Thus, type of motor is called split phase type reluctance motor.

Second type of structure is permanent split capacitor run type motor. In this motor stator produce revolving field to rotate the rotor. This type of structured motor is called capacitor type reluctance motor.

These motors have cage type unsymmetrical magnetic construction. This type of rotor provides variable magnet reluctance of stator. It means that reluctance will vary with respect to rotor.

Uses of Reluctance motor: –

Reluctance motor is inherently static speed type motor. So that  this motor is use in following application.

  • Signaling Device
  • Recording instruments
  • Timers
  • Phonograph

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