The shaded pole motor

Usually see single-phase motor are shaded pole motor,generally used in small devices start torque,such as electric fans and other small household electrical appliances.In this kind of motor,small single stage rotary concealed copper coils can produce a rotating magnetic field.Each

pole is surrounded by diesel generating copper coils or copper tape on part of the living;In order to prevent the current in the coil change (lenz's law) can produce induced current in the copper strip,so that every cycle maximum field strength across the surface,to produce a large enough lower rotating magnetic field to drive the rotor and the load on it.As the rotor increase its torque to the largest,the original (fixed) by turning the magnetic field will rotate with the rotation of the rotor.It is

difficult to reverse the motor unless internal structure change.Another common single-phase ac motor is the split-phase induction motor,such as washing machine and dryer is typically used for large household appliances.Compared with the electricalmotor1.blogspot.com shaded pole

motor,these motors can be started by winding and centrifugal switch connected together can often

provide a big start torque.In the split-phase motor,the design of the startup winding resistance than

the running winding resistance.This will generate a LR circuit,the circuit will slightly change the

phase of the current in the startup winding.When the motor is started,the start winding through a set of the above pressure with no rotation of the centrifugal switch spring connection on the power

supply.Winding start winding line is thin and less than used in the main winding line several

times,so it is a high resistance and low inductance.Low inductance and resistance rate produces a

small phase shift does not exceed 30 degrees,the phase shift is determined by the main winding

magnetic field lines and determined by the startup winding pumps magnetic field lines.Can run by changing the startup winding and winding connection to easily change the direction of rotation is

started.Start winding magnetic field phase as the grid phase changes,to produce a start the motor

rotating magnetic field.Once the motor reaches near design operating speed,the centrifugal switch

start action,shut off the connection between the startup winding to the power grid.Motor running by

running winding.Start winding must be disconnected,because it will increase the loss of the motor.