The motor star triangle start the advantages and disadvantages

Star triangle start the advantages and disadvantages of the 2009-11-23 and motor When star triangle starting method is suitable for the normal operation of the winding for the triangular connection of the motor,the three-phase winding of the motor will lead to six outlet end,and the switch.When starting,will run normally when the delta connection of the stator winding connector for star connection,change again after the starting of triangular connection.This method is only applicable to

small and medium-sized squirrel-cage asynchronous motor.Star connection,the stator winding of the stator voltage drop for 1/3,square root triangle connection is provided by the power of starting current is only 1/3 of the stator winding connection triangle.Is the ability to reduce the starting

current,this is the advantage of it.However,because the starting torque and each phase winding is

proportional to the square of the voltage and winding voltage at y connection reduces the 1/3 times

square root,so the starting torque will drop to 1/3 of the delta connection,this is its shortcomings.Since the principle of decoupling step-down start and reduce the startup of the stator

voltage,star delta starter is by changing the winding connection to change the start voltage,so the

ratio is fixed,but since the lotus root transformer ratio is adjustable,follow the same voltage drop

K,the law of the current decline in K square.Star triangle start belongs to step-down start,step-down

start the purpose is to reduce the starting current,reduce impact on other electrical appliances.Relative to the wholesalemotor.blogspot.com self coupling Motor vehicle step-down start,start star triangle is suitable for small motor capacity,widely used in 4 ~ 100 kw of asynchronous motor,the advantages of small volume,low cost,long life,reliable operation,etc.1,the same motor,wind can be installed in Y type winding and wind can also be installed in the delta type winding;

2,the same motor,the installation,type into delta winding around conductor cross section is small,serial number of turns,high work phase voltage,phase current is low;3,the same motor,the installation of Y type winding,wire section,serial number of turns small,low work voltage,phase current is high;4,delta type winding required three phase symmetry,rotor balancing machine power symmetry is higher also,so as not

to appear circulation,otherwise will be fever,increasing loss;5,Y type winding in three-phase symmetry is bad,the power symmetry is not high,there would be no circulation,but there will be zero

drift,three-phase work serious asymmetry;6,in use,delta type winding can use Y - delta start way to start,but can't use Y Y type winding - delta start way start;7,the resistance is directly

proportional to the square of the heat loss and current,so the same motor,installation into delta

type winding around heat loss is small